REVIEW | doi:10.20944/preprints202006.0256.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: cell types; nephridia; excretion; ultrafiltration; development
Online: 21 June 2020 (10:47:26 CEST)
Excretion and osmoregulation are fundamental processes of the organism, as they prevent the accumulation of toxic waste products in the body and control the osmotic differences between the cells and the environment. In most of the animals these phenomena are taking place through specialized organs, namely excretory organs, composed of diverse cell types that are performing tasks such as secretion and ultrafiltration. Although the morphology and embryology of excretory organs can differ dramatically, the common spatial arrangement of structural proteins and transporters as well as the similar transcriptional developmental programs underlying their formation suggests the homology of their cell types. In this chapter we discuss the current understanding of the evolution of excretory organsfrom a comparative morphological, developmental and functional perspective, flanked by an additional, cell-type perspective. We argue that a putative homologization of certain excretory cell types does not necessarily reflect the homology of the resulting organs, and that integrating all different levels of comparison is crucial for addressing evolutionary questions.
REVIEW | doi:10.20944/preprints202003.0110.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: cancer; cell signaling; therapeutic targets; signaling pathways
Online: 7 March 2020 (02:33:25 CET)
Cancer is a leading cause of death worldwide. It is theorized that underlying genetic and epigenetic changes enable cells to proliferate out of control by escaping regulatory mechanisms. The progression of cancer is associated with increased cell proliferation, metabolic modifications, resistance to apoptosis, genetic instability, induction of angiogenesis and augmented migratory capability. Recent developments in DNA and RNA analysis have made it possible to study these genetic changes systematically. These advances have enabled us to possess a deeper knowledge of the signaling pathways and involved processes. In-depth studies of the pathways involved in carcinogenesis have led to the identification of pathways that may be targeted for therapeutic purposes. In this review, we provide an overview of the relevant mechanisms and pathways involved in the development and progression of cancer.
ARTICLE | doi:10.20944/preprints201809.0193.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: evolutionary innovation, cell type evolution, cellular stress response, evolution of gene regulation, gene regulatory network evolution, decidual cell, evolution of pregnancy
Online: 11 September 2018 (11:41:34 CEST)
Understanding the evolutionary role of environmentally-induced phenotypic variation (i.e., environmental plasticity) is an important issue in developmental evolution. One of the major physiological responses to environmental changes is cellular stress, which is counteracted by a generic stress reaction that detoxifies the cell, refolds proteins, and repairs DNA damage. In this paper, we elaborate on a previous finding suggesting that the cell differentiation cascade of human decidual stromal cells, a cell type critical for embryo implantation and the maintenance of pregnancy, evolved from a cellular stress reaction. We hypothesize that the stress reaction in these cells was elicited ancestrally through the inflammation caused by embryo attachment and invasion. We describe a model, Stress-Induced Evolutionary Innovation (SIEI), whereby ancestral stress reactions and their corresponding pathways can be transformed into novel structural components of body plans, such as new cell types. After reviewing similarities and differences between SIEI and the “plasticity first hypothesis” (PFH) of evolution, we argue that SIEI is a distinct form of plasticity-based evolutionary change because it leads to the origin of novel structures rather than the adaptive transformation of a pre-existing character.
ARTICLE | doi:10.20944/preprints202306.0288.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Early cancer diagnosis; cell free DNA; biomarker; integrative biology; pan cancer
Online: 5 June 2023 (09:20:14 CEST)
Blood-based circulating cell free DNA(cfDNA) detection offers a non-invasive and easily accessible way for early cancer detection. Despite the extensive utility of cfDNA, there are still many challenges to develop the clinical biomarkers. For example, cfDNA with genetic alterations often compose a small portion of the DNA circulating in plasma, which can be confounded by cfDNA contributed by normal cells. Therefore, filtering out the potential false-positive cfDNA mutations from health population will be important for the cancer-based biomarkers. Additionally, many low-frequency genetic alterations are easily overlooked in small amount of cfDNA-based cancer test. We hypothesize that, the combination of diverse types of cancer studies on cfDNA can provide us a new insight to identify low-frequency genetic variant across cancer types for early clinical detection of cancers. By building a standardized computational pipeline for 1358 cfDNA samples across seven cancer types, we prioritize 129 shard genetic variants in the major cancer types. Further functional analysis of the 129 variants found that they are mainly enriched in ribosome pathways such as cotranslational protein targeting to membrane, some of which are tumor suppressor, oncogene and related to cancer initiation. In summary, our integrative analysis revealed the important roles of ribosome proteins as the common biomarkers in early cancer diagnosis.
ARTICLE | doi:10.20944/preprints202208.0341.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: Schizophrenia; cell types proportions; differential expression genes; functional pathways; CIBERSORTx
Online: 18 August 2022 (10:54:05 CEST)
Schizophrenia (SCZ) is a severe mental disorder that may result in hallucinations, delusions, and extremely disordered thinking. How each cell type in the brain contributes to SCZ occurrence is still unclear. Here, we leveraged the human dorsolateral prefrontal cortex bulk RNA-seq data, then used the RNA-seq deconvolution algorithm CIBERSORTx to generate SCZ brain single-cell RNA-seq data for a comprehensive analysis to understand SCZ-associated brain cell types and gene expression changes. Firstly, we observed that the proportions of brain cell types in SCZ differed from normal samples. Among these cell types, astrocyte, pericyte, and PAX6 cells were found to have a higher proportion in SCZ patients (astrocyte: SCZ = 0.163, Control = 0.145, P.adj = 4.9×10-4; pericyte: SCZ = 0.057, Control = 0.066, P.adj = 1.1×10-4; PAX6 : SCZ = 0.014, Control = 0.011, P.adj = 0.014), while the L5/6_IT_CAR3 cells and LAMP5 cells are the exact opposite (L5/6_IT_Car3 : SCZ = 0.102, Control = 0.108, P.adj = 0.016; LAMP5 : SCZ = 0.057, Control = 0.066, P.adj = 2.2×10-6). Next, we investigated gene expression in cell types and functional pathways in SCZ. We observed chemical synaptic transmission dysregulation in two types of GABAergic neurons (PVALB and LAMP5), and immune reaction involvement in GABAergic neurons (SST) and non-neuronal cell types (endothelial and oligodendrocyte). Furthermore, we observed that some differential expression genes from bulk RNA-seq displayed cell-type-specific abnormal in the expression of molecules in SCZ. Finally, the cell types with the SCZ-related transcriptomic changes could be considered to belong to the same module since we observed two major similar coordinated transcriptomic changes across these cell types. Together, our results offer novel insights into cellular heterogeneity and the molecular mechanisms underlying SCZ.
ARTICLE | doi:10.20944/preprints202311.0949.v1
Subject: Computer Science And Mathematics, Artificial Intelligence And Machine Learning Keywords: Convolutional Neural Net (CNN); Vision Transformer (ViT); ImageNet Models; Transfer Learning (TL); Machine Learning (ML); Deep Learning (DP); Blood Cell Classification, Peripheral Blood Cell (PBC), CBAM, Naturalize
Online: 14 November 2023 (15:18:08 CET)
In this paper, we redefine the boundaries of blood cell classification, expanding from 5 to 11 distinct blood cell types using the challenging 11-class PBC dataset. This shift enables a deeper understanding of blood cell diversity, overcoming previous limitations in medical image analysis. Our approach combines state-of-the-art deep learning techniques, including pre-trained ConvNets, ViTb16 models, and custom CNN architectures. We employ transfer learning, fine-tuning, and ensemble strategies, such as CBAM and Averaging ensembles, to achieve unprecedented accuracy and interpretability. Our fully fine-tuned EfficientNetV2 B0 model sets a new standard, with a macro-average precision, recall, and F1-score of 91%, 90%, and 90%, respectively, and an average accuracy of 93%. This breakthrough underscores the transformative potential of 11-class blood cell classification for more precise medical diagnoses. Moreover, our groundbreaking "Naturalize" augmentation technique produces remarkable results. The 2K-PBC dataset generated with "Naturalize" boasts a macro-average precision, recall, and F1-score of 97%, along with an average accuracy of 96% when leveraging the fully fine-tuned EfficientNetV2 B0 model. This innovation not only elevates classification performance but also addresses data scarcity and bias in medical deep learning. Our research marks a paradigm shift in blood cell classification, enabling more nuanced and insightful medical analyses. The "Naturalize" technique’s impact extends beyond blood cell classification, emphasizing the vital role of diverse and comprehensive datasets in advancing healthcare applications through deep learning.
ARTICLE | doi:10.20944/preprints202010.0600.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: cell proliferation; human gingival fibroblasrs; photobiomodulation PBM; soft tissue regeneration
Online: 29 October 2020 (09:20:47 CET)
Purpose: to assess the effect of photobiomodulation (PBM) on human gingival fibroblast proliferation. Methods: The study was conducted using the primary cell cultures of human fibroblasts collected from systemically healthy donors. Three different laser types: Nd:YAG (1064nm), infrared diode laser (980nm) and prototype led laser emitting 405, 450 and 635nm were used to irradiate fibroblasts. Thanks to the patented structure of that laser, it was possible to irradiate fibroblasts with a beam combining two or three wavelengths. The energy density was 3 J/cm², 25 J/cm², 64 J/cm². The viability and proliferation of cells were determined using the MTT test conducted 24, 48 and 72 hours after laser irradiation. Results: The highest percentage of mitochondrial activity (MA=122.1%) was observed in the group irradiated with the 635nm laser, with an energy density of 64 J/cm² after 48 hours. The lowest percentage of MA (94.0%) was observed in the group simultaneously irradiated with three wavelengths (405 + 450 + 635 nm). The use of the 405nm laser at 25 J/cm² gave similar results to the 635 nm laser. Conclusions: The application of the 635nm and 405nm irradiation caused a statistically significant increase in the proliferation of gingival fibroblasts.
COMMUNICATION | doi:10.20944/preprints201901.0161.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: stem cell; stromal cell; mesenchymal stromal cell; regeneration; cell sheet; cell delivery
Online: 16 January 2019 (09:39:55 CET)
Regeneration is a fundamental process much attributed to functions of adult stem cells. In last decades delivery of suspended adult stem cells is widely adopted in regenerative medicine as a leading mean of cell therapy. However, adult stem cells can not complete the task of human body regeneration effectively by themselves as far as they need a receptive microenvironment (the niche) to engraft and perform properly. Understanding of mechanisms underlying mammalian regeneration lead us to an assumption that improved outcomes of cell therapy requires a specific microenvironment generated in damaged area prior to stem cell delivery. To certain extent it may be achieved by delivery of mesenchymal stromal cells (MSC), not in dispersed form, but rather self-organized in cell sheets (CS) – tissue-like structures comprising of viable cells and microenvironment components: extracellular matrix and soluble factors deposited in the matrix. In this communication we highlight a potential role of mesenchymal stromal cells (MSC) as regeneration organizers and speculate that this function emerges in CS. This concept shifts our understanding of therapeutic mechanism underlying a widely known CS-based delivery method for regenerative medicine.
HYPOTHESIS | doi:10.20944/preprints201812.0238.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: stem cell, stromal cell, mesenchymal stromal cell, regeneration, histogenesis, cell sheet, cell delivery
Online: 19 December 2018 (16:22:42 CET)
Regeneration is a fundamental perpetual tissue process much attributed to functions of adult stem cell. In last decades delivery of adult stem cells to restore tissue structure is widely adopted in regenerative medicine. However, delivery of stem cells can not complete the task of human body regeneration effectively as far as cells need a basis to form a tissue. Certain improvement can be achieved when cells are organized to cells sheets (CS) – primitive tissue-engineered structures comprising of viable cells and ECM proteins. This led us to an assumption that after damage an intermediate feeder is structure formed as a ground for future tissue resulting in gradients of stimuli required to attract other cells (vascular, neural, epithelial, parenchyma etc.) in an organized manner. This feeder acquires increasing heterogeneity and becomes a guiding feeder that provides basic level of organization to increase complexity of structure up to normal tissue. We also highlight potential role of adult mesenchymal stromal cells (MSC) as the main source of guiding feeder and support it by our recent knowledge of their biological function. Finally, we assume that CS known to be a feasible delivery tool in therapeutics resemble guiding feeder and show our own data indicating properties of MSC-based CS. Furthermore, this concept shifts our understanding of therapeutic mechanism underlying a widely known delivery method for regenerative medicine.
ARTICLE | doi:10.20944/preprints202311.0069.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: Cell Migration; Cancer cell migration; normal epithelial cell motility
Online: 1 November 2023 (11:18:02 CET)
Cellular locomotion is required for survival, fertility, proper embryonic development, regeneration, and wound healing. Cell migration is a major component of metastasis, which accounts for two-thirds of all solid tumor deaths. While many studies have demonstrated increased energy requirements, metabolic rates, and migration of cancer cells compared to normal cells, few have systematically compared normal and cancer cell migration as well as energy requirements side by side. Thus, we investigated how non-malignant and malignant cells migrate utilizing several cell lines from the breast and lung. Initial screening was done in an unbiased high-throughput manner for the ability to migrate/invade on collagen and/or Matrigel. We unexpectedly observed that all the non-malignant lung cells moved significantly faster than cells derived from lung tumors regardless of growth media used. Given the paradigm-shifting nature of our discovery, we pursued possible mechanisms responsible. Neither mass, cell doubling, nor volume, accounted for the individual speed and track length of the normal cells. Non-malignant cells had higher levels of ATP at premigratory-wound induction stages. Meanwhile, cancer cells also increased ATP at premigratory-wound induction – but not to the levels of the normal cells, indicating the possibility for further therapeutic investigation.
CASE REPORT | doi:10.20944/preprints202309.2139.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: Peripheral giant-cell granuloma; giant-cell epulis; giant- cell hyperplasia
Online: 30 September 2023 (07:21:15 CEST)
The Peripheral giant cell granuloma (PGCG) is an asymptomatic, non-neoplastic and proliferative lesion of unknown etiology. Some possible pre-disposing factors such as hormonal changes dur-ing pregnancy, have been suggested. However, the association between PGCG and pregnancy is controversial. There are few reported clinical cases of pregnancy-associated PGCG in the litera-ture, and they occurred only in the lower jaw. The present report is on a 35-year-old female pa-tient at 36 weeks of gestation who presented with a PGCG in the central and lateral incisors of the upper jaw. The management consisted of surgical excision, along with curettage of the affected bony walls. The diagnosis was based on clinical results and imaging examinations, and it was histopathologically confirmed. The patient underwent postoperative follow-up evaluations at 3, 6 and 12 months, and there were no signs of recurrence.
ARTICLE | doi:10.20944/preprints202304.0758.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: marigold; callus; cell suspension; growth parameters; cell viability; stem cell
Online: 23 April 2023 (04:05:25 CEST)
Plant stem cell cultures have so far been established in only a few plant species using cambial meristematic cells. The presence of stem cells or stem cell-like cells in other organs and tissues of the plant body, as well as the possibility of de novo generation of meristematic cells from differentiated cells, allows to consider the establishment of stem cell cultures in a broader range of species. Therefore, this study aimed to establish a stem cell culture of the medicinal plant Calendula officinalis L. Callus tissues were induced from explants taken from leaves and roots. Appropriate combinations of plant growth regulators and light parameters for in vitro cultivation were selected. Already at this stage, stem and dedifferentiated cells could be identified, and cell suspension cultures were established from specific parts of the formed callus. Cell suspension cultures with a high proportion of stem cells originating from roots (92–93%) or leaves (72–73%) were developed. The amount of stem cells derived from the roots in the cell suspension reached a plateau at a level of 5.60–5.72105.
HYPOTHESIS | doi:10.20944/preprints202201.0171.v3
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: ATP; Cancer cell; Cancer Treatment; Mitochondria; T cell
Online: 27 June 2022 (05:07:50 CEST)
Like living organisms, cancer cells require energy to survive and interact with their environment. Mitochondria are the main organelles for energy production and cellular metabolism. Recently, investigators demonstrated that cancer cells can hijack mitochondria from immune cells. This behavior sheds light on a pivotal piece in the cancer puzzle, the ‘dependence’ on the normal cells. This article illustrates the benefits of new, functional mitochondria for cancer cells that urge them to hijack mitochondria. It describes how functional mitochondria help cancer cells’ survival in the harsh tumor microenvironment, immune evasion, progression, and treatment resistance. Recent evidence has put forward the pivotal role of mitochondria in cancer stem cells’ metabolism. This theory highlights the mitochondria in cancer biology and explains how targeted anti-mitochondrial treatments can improve oncological outcomes.
REVIEW | doi:10.20944/preprints202311.1711.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: cell proliferation; cell fate; ERK; senescence; cell signaling; EMT; apoptosis; pluripotency
Online: 28 November 2023 (08:10:31 CET)
This comprehensive review delves into the multifaceted aspects of ERK signaling and the intricate mechanisms underlying distinct cellular fates. ERK1 and ERK2 (ERK) govern proliferation, transformation, epithelial-mesenchymal transition, differentiation, senescence, or cell death, con-tingent upon activation strength, duration, and context. The biochemical mechanisms underlying these outcomes are inadequately understood, shaped by signaling feedback and the spatial localization of ERK activation. Generally, ERK activation aligns with the Goldilocks principle in cell fate determination. Excessive or insufficient ERK activity inhibits growth, whereas moderated activation supports proliferation and survival. Unraveling the intricacies of how the degree of ERK activation dictates cell fate requires deciphering mechanisms encompassing protein stability, transcription factors downstream of ERK, and the chromatin landscape.
REVIEW | doi:10.20944/preprints202309.2044.v1
Subject: Engineering, Chemical Engineering Keywords: photocatalytic water splitting; photoelectrochemical cell; dye solar cell; tandem solar cell; hydrogen
Online: 29 September 2023 (08:05:11 CEST)
A sustainable, scalable source of energy‐dense chemical fuel is urgently needed to ensure the security of our energy supply for future generations. Solar energy is the only renewable energy source of sufficient scale to replace fossil fuels and meet rising environmental demand. Hydrogen is expected to play a key role as an energy carrier in future energy systems of the world. As fossil fuel supplies become scarcer and environmental concerns increase, hydrogen is likely to become an increasingly important chemical energy carrier and eventually may become the principal chemical energy carrier. When most of the world’s energy sources become non-fossil based, hydrogen and electricity are expected to be the two dominant energy carriers for the provision of end-use services. Photocatalytic hydrogen evolution from water by solar energy over semiconductors offers a promising way for clean and renewable production of hydrogen. The TiO2-based materials have received considerable attention in recent years due to their extensive application in photocatalysis for hydrogen evolution. Though TiO2 is the most widely investigated photocatalyst for hydrogen evolution, it still provides low photocatalytic activity due to the wide bandgap that results in photocatalytic activity only under ultraviolet (UV) irradiation. Modification of TiO2 photocatalysts with several transition metals has been extensively studied to extend the absorbance capacity of TiO2 into the visible range. The effect of different photocatalytic deposition and reaction parameters also play major roles in enhancing the photostability of photoanode and increasing the hydrogen gas output, respectively.
ARTICLE | doi:10.20944/preprints201803.0185.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: induced cardiomyocyte; epigenetic reprogramming; cell division; cell-cycle synchronization; cell-cycle exit
Online: 21 March 2018 (05:29:25 CET)
Direct reprogramming of fibroblasts into induced cardiomyocytes (iCMs) holds a great promise for regenerative medicine and has been studied in several major directions. However, cell-cycle regulation, a fundamental biological process, has not been investigated during iCM-reprogramming. Here, our time-lapse imaging on iCMs, reprogrammed by Gata4, Mef2c, and Tbx5 (GMT) monocistronic retroviruses, revealed that iCM-reprogramming was majorly initiated at late-G1- or S-phase and nearly half of GMT-reprogrammed iCMs divided soon after reprogramming. iCMs exited cell cycle along the process of reprogramming with decreased percentage of EdU+/αMHC-GFP+ cells. S-phase synchronization post-GMT-infection could enhance cell-cycle exit of reprogrammed iCMs and yield more GFPhigh iCMs, which achieved an advanced reprogramming with more expression of cardiac genes than GFPlow cells; however, S-phase synchronization didn’t enhance the polycistronic-MGT reprogramming, in which cell-cycle exit had been accelerated. In conclusion, post-infection synchronization of S-phase facilitated the early progression of GMT-reprogramming through a mechanism of enhanced cell-cycle exit.
ARTICLE | doi:10.20944/preprints202309.0032.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: breast cancer; microRNAs; 2D cell culture; 3D cell culture; organotypic 3D cell culture
Online: 1 September 2023 (07:47:04 CEST)
Background. Currently, most of the research in breast cancer has been carried out in conventional two-dimensional (2D) cell culture due to its practical benefits, however, the three-dimensional (3D) cell culture is becoming the model of choice in cancer research because it allows cell-cell and cell-extracellular matrix (ECM) interactions, mimicking the native microenvironment of tumors in vivo. Methods. in this work, we evaluated the effect of 3D cell organization on the expression pattern of miRNAs (by Small-RNAseq) and mRNAs (by microarrays) in the breast cancer SKBR3 cell line and analyzed the biological processes and signaling pathways regulated by the differ-entially expressed protein-coding genes (DE-mRNAs) and miRNAs (DE-microRNAs) found in the organoids. Results. We obtained well-defined cell-aggregated organoids with a grape cluster-like morphology with a size up to 9.2×105 μm3. The transcriptomic assays showed that cell growth in organoids significantly affected (all p < 0.01) the gene expression patterns of both, miRNAs and mRNAs, finding 20 upregulated and 19 downregulated DE-microRNAs, as well as 49 upregulated and 123 downregulated DE-mRNAs. In silico analysis showed that a subset of 11 upregulated DE-microRNAs target 70 downregulated DE-mRNAs. These genes are involved in 150 gene on-tology (GO) biological processes such as regulation of cell morphogenesis, regulation of cell shape, regulation of canonical Wnt signaling pathway, morphogenesis of epithelium, regulation of cy-toskeleton organization, as well as in the MAPK and AGE-RAGE signaling KEGG-pathways. In-terestingly, hsa-mir-122-5p (Fold Change (FC)=15.4), hsa-mir-369-3p (FC=11.4), and hsa-mir-10b-5p (FC=20.1) regulated up to the 81 % of the 70 downregulated DE-mRNAs. Conclu-sion, the organotypic 3D cell-organization architecture of breast cancer SKBR3 cells impacts the expression pattern of miRNAs-mRNAs network mainly through overexpression of hsa-mir-122-5p, hsa-mir-369-3p, and hsa-mir-10b-5p. All these findings suggest that the interaction between cell-cell and cell-ECM as well as the change in the culture architecture impacts gene ex-pression, and therefore, support the pertinence of migrating breast cancer research from conven-tional cultures to 3D models.
REVIEW | doi:10.20944/preprints201905.0386.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: CRISPR, clonal selection, totipotent, multipotent, T cell receptors, B cell receptors, precommitted, lymphocyte, T cell vaccine, T cell vaccination
Online: 31 May 2019 (11:12:33 CEST)
Transfer factor is the name given to material derived from activated lymphocytes that is probably composed of a complex of a peptide and a short segment of RNA and which has the reported ability to transfer specific T cell immunity to uncommitted lymphocytes. Many independent groups around the world reported isolating transfer factors between 1955 and 1990 and demonstrating their ability to transfer passive immunity from one animal or individual to another, often within 24 hours of inoculation. Such activity is potentially revolutionary both in making T cell vaccines readily manufacturable and also because the existence of transfer factors would undermine the basic assumptions of the clonal selection theory, which currently dominates immunological theory. Unfortunately, lack of the microanalytical and synthetic techniques required to properly identify transfer factors, combined with safety factors associated with it derivation from blood sources susceptible to HIV and prion infections, put an end to transfer factor research after 1990. This paper reviews the evidence supporting transfer factor activity and suggests that this potentially revolutionary concept be resurrected and subjected to renewed scrutiny in light of CRISPR-Cas mechanisms and because of its potential to make possible T cell vaccination and provide a novel basis for understanding immunological function.
REVIEW | doi:10.20944/preprints202308.0083.v1
Subject: Engineering, Bioengineering Keywords: single-cell analysis; electrical manipulation; single-cell application
Online: 1 August 2023 (10:50:09 CEST)
Biological parameters extracted from electrical signals from various body parts have been used for many years to analyze the human body and its behavior. In addition, electrical signals from cancer cell lines, normal cells, and viruses, among others, have been widely used for the detection of various diseases. Single-cell parameters such as cell and cytoplasmic conductivity, relaxation frequency, and membrane capacitance are important. There are many techniques available to characterize biomaterials, such as scanning tunneling microscopy (STM), nanotechnology, microstrip cavity resonance measurement, dielectric impedance measurement (DEPIM), etc. This article reviews the single cell isolation and sorting techniques, summarizes the common single cell operations such as impedance flow cytometry, cell electrical impedance, electrical impedance sensing, and summarizes the current single cell analysis techniques and their applications.
ARTICLE | doi:10.20944/preprints202306.1812.v1
Subject: Engineering, Energy And Fuel Technology Keywords: Liquid cooling; Longitudinal flow; Cylindrical cell; Dummy cell
Online: 26 June 2023 (12:18:01 CEST)
A new longitudinal flow heat dissipation theory for cylindrical batteries is proposed in order to increase the energy density and uniform temperature performance of cylindrical lithium-ion battery packs while also shrinking their size by roughly 10%. First, a genetic algorithm is used to identify the single cell's thermal properties. Based on this, modeling and simulation are used to examine the thermal properties of the longitudinal flow-cooled battery pack. It is found that the best coolant flow scheme has one inlet and one outlet from the end face, taking into account the cooling effect of the battery pack and engineering viability. Lastly, Thermal Dummy Cells (TDC) is used to conduct a validation test of the liquid cooling strategy. Additionally, the simulation and test results demonstrated that the liquid cooling solution can keep the battery pack's maximum temperature rise under the static conditions of a continuous, high-current discharge at a rate of 3C to 20 °C and under the dynamic conditions of the New European Driving Cycle (NEDC) to 2 °C. In applications where the space requirements for the battery pack are quite severe, the longitudinal flow cooling method has some advantages.
REVIEW | doi:10.20944/preprints202306.0952.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: mTOR; CD8 T cell; NK cell; cytokine signaling
Online: 13 June 2023 (15:45:23 CEST)
CD8 T cells and Natural Killer (NK) cells are cytotoxic lymphocytes important in the response to intracellular pathogens and cancer. Their activity depends on the integration of a large set of intracellular and environmental cues, including antigenic signal, cytokine stimulation and nutrients availability. This integration is achieved by signaling hubs such as the mechanistic target of Rapamycin (mTOR). mTOR is a conserved protein kinase, controlling cellular growth and metabolism in eukaryotic cells and therefore is essential for lymphocyte development and maturation. However, our current understanding of mTOR signaling comes mostly from studies performed in transformed cell lines, which constitute a poor model to comprehend metabolic pathway regulation. Therefore, it is only quite recently that the regulation of mTOR in primary cells has been assessed. Here we review the signaling pathways leading to mTOR activation in CD8 T and NK cells, focusing on activation by cytokines. We also discussed how this knowledge can contribute to immunotherapy development for intracellular pathogen and cancer treatment.
ARTICLE | doi:10.20944/preprints202305.0482.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Mitochondria; Personalized Oncology; cancer stem cell; T Cell
Online: 8 May 2023 (08:48:56 CEST)
Energy is needed by cancer cells to stay alive and communicate with their surroundings. The primary organelles for cellular metabolism and energy synthesis are mitochondria. Researchers recently proved that cancer cells can steal immune cells' mitochondria using nanoscale tubes. This finding demonstrates the dependence of cancer cells on normal cells for their living and function. It also denotes the importance of mitochondria in cancer cells’ biology. Emerging evidence has demonstrated how mitochondria are essential for cancer cells to survive in the harsh tumor microenvironment, evade the immune system, obtain more aggressive features, and resist treatments. For instance, functional mitochondria can improve cancer resistance against radiotherapy by scavenging the released reactive oxygen species. Therefore, targeting mitochondria can potentially enhance oncological outcomes, according to this notion. The patients' reactions to radiation are varied, ranging from a complete response to even cancer progression during treatment. This concept illustrates how different levels of mitochondrial metabolism might contribute to this heterogeneity. Considering this notion can help to improve personalized oncological treatments. This article outlines the importance of mitochondrial metabolism in cancer biology and personalized treatments.
REVIEW | doi:10.20944/preprints202111.0250.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: cell fusion; tumor hybrid cell; metastasis; drug resistance
Online: 15 November 2021 (11:07:48 CET)
Metastasis is the leading cause of cancer death and can be realized through the phenomenon of tumor cell fusion. The fusion of tumor cells with other tumor or normal cells leads to the appearance of tumor hybrid cells (THCs) exhibiting novel properties such as increased proliferation and migration, drug resistance, decreased apoptosis rate and avoiding immune surveillance. Experimental studies showed the association of THCs with a high frequency of cancer metastasis; however, the underlying mechanisms remain unclear. Many other questions also remain to be answered: the role of genetic alterations in tumor cell fusion, the molecular landscape of cells after fusion, the lifetime and fate of different THCs, and the specific markers of THCs, and their correlation with various cancers and clinicopathological parameters. In this review, we discuss the factors and potential mechanisms involved in the occurrence of THCs, the types of THCs, and their role in cancer drug resistance and metastasis, as well as potential therapeutic approaches for the prevention and targeting of tumor cell fusion. In conclusion, we emphasize the current knowledge gaps in the biology of THCs that should be addressed to develop highly effective therapeutics and strategies for metastasis suppression.
ARTICLE | doi:10.20944/preprints201901.0149.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: endosymbiosis, germline, vertical transmission, cell-to-cell transfer
Online: 15 January 2019 (09:55:25 CET)
Microbial symbioses exhibit astounding adaptations, yet all symbionts face the problem of how to reliably associate with host offspring every generation. A common strategy is vertical transmission, in which symbionts are directly transmitted from the female to her offspring. The diversity of symbionts and vertical transmission mechanisms is as expansive as the diversity of eukaryotic host taxa that house them. However, there are several common themes among these mechanisms based on the degree to which symbionts associate with the host germline during transmission. In this review, we detail three distinct vertical transmission strategies, starting with associations that are transmitted from host somatic cells to offspring somatic cells, either due to lacking a germline or avoiding it. A second strategy involves somatically-localized symbionts that migrate into the germline during host development. The third strategy we discuss is one in which the symbiont maintains continuous association with the germline throughout development. Unexpectedly, the vast majority of documented vertically inherited symbionts rely on the second strategy: soma-to-germline migration. Given that not all eukaryotes contain a sequestered germline and instead produce offspring from somatic stem cell lineages, this soma-to-germline migration is discussed in the context of multicellular evolution. Lastly, as recent genomics data have revealed an abundance of horizontal gene transfer events from symbiotic and non-symbiotic bacteria to host genomes, we discuss their impact on eukaryotic host evolution.
ARTICLE | doi:10.20944/preprints201701.0137.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: cell culture; bioreactor; live cell imaging; tissue engineering
Online: 31 January 2017 (12:39:46 CET)
Here, we present a staged approach for an innovative repurposing of a portable infant humidicrib into a live cell growth, observation, and imaging system. Furthmore, humidicrib can support different variations of “umbilical” bioreactors, and can be used to conduct electrophysiology experiments and in situ immunohistochemistry. Modifications incorporate a closed loop carbon dioxide (CO2) concentration control system with umbilical CO2 and heating support for tailored bioreactors. The repurposing cost is inexpensive and allows for the continued observation and imaging of cells. This prototype unit has been used to continuously observe and image live primary neurons for up to 21 days. This demonstrates the repurposed units’ suitability for use in tissue culture based research, particularly where modifications to microscopes are required or where sensitive manipulation outside of a standard incubator is needed.
ARTICLE | doi:10.20944/preprints201712.0159.v1
Subject: Computer Science And Mathematics, Analysis Keywords: mathematical modeling; biological networks; sensitivity analysis; programmed cell death; single cell dynamics; cell population
Online: 22 December 2017 (01:48:00 CET)
Studies performed at single-cell resolution have demonstrated the physiological significance of cell-to-cell variability. Various types of mathematical models and systems analyses of biological networks have further been used to gain a better understanding of the sources and regulatory mechanisms of such variability. In this work, we present a novel sensitivity analysis method, called molecular density function perturbation (MDFP), for the dynamical analysis of cellular heterogeneity. The proposed analysis is based on introducing perturbations to the density or distribution function of the cellular state variables at specific time points, and quantifying how such perturbations affect the state distribution at later time points. We applied the MDFP analysis to a model of signal transduction pathway involved in TRAIL (tumor necrosis factor-related apoptosis-inducing ligand)-induced apoptosis in HeLa cells. The MDFP analysis showed that caspase-8 activation regulates the timing of the switch-like increase of cPARP (cleaved poly(ADP-ribose) polymerase), an indicator of apoptosis. Meanwhile, the cell-to-cell variability in the commitment to apoptosis depended on mitochondrial outer membrane permeabilization (MOMP) and events following MOMP, including the release of Smac (second mitochondria-derived activator of caspases) and cytochrome-C from mitochondria, the inhibition of XIAP (X-linked inhibitor of apoptosis) by Smac and the formation of apoptosome.
REVIEW | doi:10.20944/preprints202308.2151.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Medicinal and edible plants; cell cultures; cell fusion; somatic hybridization; artificial polyploidy induction; cell engineering
Online: 31 August 2023 (07:52:44 CEST)
With worsening environmental degradation and increasing international demand for human health, plant cell based technology will be more important. The aim of this review is to give an overview regarding key points of current progress and development trend of nature medical and edible plants from the framework of whole plant cell engineering including cell cultures, cell fusion and cell splitting derived biotechnology. Here we sum up three main application trends of medical plants cell cultures covering industrial output, technology upgrading and potential resource development. We also provide classification and typification insights to summarize the development of somatic hybridization in cereal, vegetables crops and other medicinal and edible plants as well as application of artificial polyploidy induction in major medicinal herbs. Development medicinal and edible homologous plants based on modern plant cell engineering will bring us a promising future.
ARTICLE | doi:10.20944/preprints201808.0431.v1
Subject: Biology And Life Sciences, Virology Keywords: HIV, cell-to-cell transmission, designer antigens, neutralizing antibody, cell-free, high multiplicity of infection
Online: 24 August 2018 (10:25:33 CEST)
Viruses can infect a cell via one or both routes viz. cell-to-cell (c-c) or cell-free (c-f) . Pathogenesis studies of various viruses, including HIV, have shown that c-c transmission yields a significantly higher infection magnitude than the c-f route. Expectedly, potent antibodies inhibited c-f infection more efficiently than with c-cell transmission. To achieve a one-step, synchronous infection cycle that provides amplified infection, we have studied a consistent and efficient c-c HIV infection model since 1992. H9 cells persistently infected with HTLV-IIIB (H3B cells) and uninfected target CD4+ lymphocyte line (HuT78) were mixed in a ratio of 1:4 respectively. We have recently used this model to produce HIV designer antigens that have been shown to elicit monoclonal as well as polyclonal specific antibodies against novel epitopes that are formed post virus-cell engagement, but prior to fusion. The model can be extended for HIV neutralizing antibody assays or drug inhibitors against high multiplicity of infection.
REVIEW | doi:10.20944/preprints202307.2055.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: CD4+ T cell; Primary Immunodeficiencies; Cell Migration; Adaptive Immunity
Online: 31 July 2023 (10:04:55 CEST)
CD4+ T cells orchestrate and regulate immunity within jawed vertebrates, yet our understanding of their evolution, development, and cellular physiology has only begun to be unearthed in the past few decades. Discoveries of genetic diseases that ablate this cellular population have provided insight into their critical functions while transcriptomics, proteomics, and highresolution microscopy have recently revealed new insights into CD4+ T cell anatomy and physiology. This article compiles historical, microscopic, and multi omics data which can be used as a reference atlas to dissect cellular physiology within these influential cells and further understand pathologies like HIV infection that inflict human CD4+ T cells.
REVIEW | doi:10.20944/preprints202108.0387.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: CART CELL, ZFNs, TALEN, TCR T-CELL, CRISPR Cas9
Online: 18 August 2021 (14:21:46 CEST)
Novel Cellular Immunotherapy with engineered T cells has improved cancer treatment and established therapeutic promises to prevent tumor formation in clinical studies. Due to certain restrictions and difficulties, CAR and TCR T cells therapies were inadequate at points. CRISPR Cas9 genome-editing tool has a significant potential for these two cell-based therapies. As a specialized gene-editing technique, CRISPR Cas9 is used to repair genetic alternation with minimum damage. It is used as an adjunct to Immunotherapy to stimulate a more robust immune response. CRISPR has long outpaced other target-specific genome editing methods such as ZFNs and TALEN due to its high efficiency, competence in targeting, and stable operating condition. CRISPR can overcome the two major drawbacks of universal CAR T cells: allorejection and graft-vs-host disease. TCR-based T cell treatment can reduce inappropriate binding between endogenous and transgenic TCR, resulting in a reduction of severe toxicity. The CAR and TCR T based cell therapies uphold an excellent future for tumor malignancies This article has elucidated the administration of CRISPR Cas9 in Novel Cellular Immunotherapy, CAR, and TCR T cell therapy. However, this article did not fail to observe this technology's ethical concerns, limitations, and challenges. Furthermore, the article compares CRISPR-mediated allogeneic CAR T cell to TCR-T cell therapy.
BRIEF REPORT | doi:10.20944/preprints202002.0167.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: 2019-nCoV; Immune; B cell; T cell; COVID-19
Online: 13 February 2020 (10:53:40 CET)
The outbreak of the 2019 Novel Coronavirus (2019-nCoV) has rapidly spread from Wuhan, China to multiple countries, causing staggering number of infections and deaths. A systematic profiling of the immune vulnerability landscape of 2019-nCoV is lacking, which can bring critical insights into the immune clearance mechanism, peptide vaccine development, and antiviral antibody development. In this study, we predicted the potential of all the 2019-nCoV viral proteins to induce class I and II MHC presentation and form linear antibody epitopes. We showed that the enrichment for T cell and B cell epitopes is not uniform on the viral genome, with several focused regions that generate abundant epitopes and may be more targetable. We showed that genetic variations in 2019-nCoV, though fewer for the moment, already follow the pattern of mutations in related coronaviruses, and could alter the immune vulnerability landscape of this virus, which should be considered in the development of therapies. We create an online database to broadly share our research outcome. Overall, we present an immunological resource for 2019-nCoV that could significantly promote both therapeutic development and mechanistic research.
CASE REPORT | doi:10.20944/preprints201912.0185.v2
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: Eye; Corneal ulcer; Canine; Mesenchymal stem cell; Cell Therapy
Online: 16 December 2019 (11:32:08 CET)
Corneal ulcer (CU) is an ophthalmopathy characterized by depression of the corneal surface with at least one stromal loss. CU is common in canine and feline species and is usually caused, among others, by trauma, infections, toxic contamination and endocrine disorders. They usually result from an increased inflammatory response and are associated with some clinical signs such as blepharospasm, photophobia, epiphora, pain and loss of corneal transparency. Despite advances in conventional and pharmacological therapy, in many cases indolent and recurrent ulcer treatments still lead to loss of visual acuity of the animal. This paper aims to report the effect of topical application of canine adipose tissue-derived mesenchymal stem cell (cATMSCs) as treatment of recurrent CU in a Poodle dog breed that showed clear difficulty in the healing process associated with diabetes. The animal was submitted to two applications of cATMSCs and showed improvement in the blepharospasm, conjunctival hyperemia, mucopurulent ocular secretion, photophobia, corneal opacity, chemosis, pigmentation, neovascularization, and pain parameters. Besides, Fluorescein test, Schirmer test and ocular fundus exam also showed improvement in their values concomitantly with lesion resolution. Due this, we showed that cATMSC therapy contribute to the regeneration of corneal tissue in CU and may contribute to the treatment to others ophthalmopathies.
ARTICLE | doi:10.20944/preprints201810.0768.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: silybin; prostate cancer; 2,3-dehydrosilybin; cell proliferation; cell apoptosis.
Online: 1 November 2018 (18:16:29 CET)
As part of our ongoing silybin project, this study aims to introduce a basic nitrogen-containing group to 7-OH of 3,5,20-O-trimethyl-2,3-dehydrosilybin or 3-OH of 5,7,20-O-trimethyl-2,3-dehydrosilybin via an appropriate linker for in vitro evaluation as potential anti-prostate cancer agents. The synthetic approaches to 7-O-substituted-3,5,20-O-trimethyl- 2,3-dehydrosilybins through a five-step procedure and to 3-O-substituted-5,7,20-O-trimethyl-2,3- dehydrosilybins via a four-step transformation have been developed. Thirty-two nitrogen-containing derivatives of silybin have been achieved through these synthetic methods for the evaluation of their antiproliferative activities towards both androgen-sensitive (LNCaP) and androgen-insensitive prostate cancer cell lines (PC-3 and DU145) using WST-1 cell proliferation assay. These derivatives exhibited greater in vitro antiproliferative potency than silybin. Among them, 11, 29, 31, 37, and 40 were identified as five optimal derivatives with IC50 values in the range of 1.40–3.06 µM, a 17- to 52-fold improvement in potency as compared with silybin. All these five optimal derivatives can arrest the PC-3 cell cycle in the G0/G1 phase and promote PC-3 cell apoptosis. Derivatives 11, 37, and 40 are more effective than 29 and 31 in activating PC-3 cell apoptosis.
ARTICLE | doi:10.20944/preprints201808.0357.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Astragalin galactoside, hydrophilic modification, Th1 cell, Dendritic cell, adjuvant
Online: 20 August 2018 (12:58:07 CEST)
A flavonoid Astragalin (kaempferol-3-O-β-D-glucopyranoside, Ast) has several biological activities including anti-oxidant, anti-HIV, and anti-allergic effects. Nonetheless, its insolubility in hydrophilic solvents imposes restrictions on its therapeutic applications. In this study, we investigated the effects of water-soluble astragalin-galactoside (kaempferol-3-O- β-D-isomaltotrioside, Ast-Gal) on dendritic cell (DC) maturation and T helper (Th) cell-mediated immune responses. Ast-Gal significantly increased maturation and activation of DCs through up-regulation of surface markers, such as CD80, CD86, and MHC II in a dose-dependent manner, while Ast had little effects. Also, Ast-Gal-treated DCs markedly secreted immune-stimulating cytokines such as IL-1β, IL-6, and IL-12. Importantly, Ast-Gal strongly increased expression of IL-12, a polarizing cytokine of Th1 cells. In a co-culture system of DCs and CD4+ T cells, Ast-Gal-treated DCs preferentially differentiates naïve CD4+ T cells into Th1 cells. The addition of neutralizing IL-12 mAb to cultures of Ast-Gal-treated DCs and CD4+ T cells significantly increased IFN- γ production, thereby indicating that Ast-Gal-stimulated DCs enhance the Th1 response through IL-12 production by DCs. Injection with Ast-Gal-treated DCs in mice increased IFN-γ-secreting Th1 cell population. Collectively, these findings indicate that hydrophilically modified astragalin can enhance Th1-mediated immune responses via DCs, and point to a possible application of water-soluble astragalin-galactoside as an immune adjuvant.
REVIEW | doi:10.20944/preprints201702.0098.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: MicroRNA; cancer associated fibroblasts; cell-cell communication; transformation; epigenetic
Online: 28 February 2017 (10:29:27 CET)
Tumor microenvironment including cancer-associated fibroblasts (CAF) has developed as an important target for understanding tumor progression, clinical prognosis and treatment responses of cancer. Cancer cells appear to transform normal fibroblasts (NF) into CAFs involving direct cell-cell communication and epigenetic regulations. This review summarizes the current understanding on miR involvement in cancer cell – tumor environment/stroma communication, transformation of NFs into CAFs, their involved targets and signaling pathways in these interactions; and clinical relevance of CAF-related miR expression profiles. There is evidence that miRs have very similar roles in activating hepatic (HSC) and pancreatic stellate cells (PSC) as part of precancerous fibrotic diseases. In summary, deregulated miRs affect various intracellular functional complexes, such as transcriptional factors, extracellular matrix, cytoskeleton, EMT/MET regulation, soluble factors, tyrosine kinase and G-protein signaling, apoptosis and cell cycle & differentiation, but also formation and composition of the extracellular microenvironment. These processes result in the clinical appearance of desmoplasia involving CAFs and fibrosis characterized by deregulated stellate cells. In addition, modulated release of soluble factors can act as (auto)activating feedback loop for transition of NFs into their pathological counterparts. Furthermore, epigenetic communication between CAFs and cancer cells may confer to cancer specific functional readouts and transition of NF into their pathological counterparts. MiR related epigenetic regulation with many similarities should be considered as key factor in development of cancer and fibrosis specific environment.
ARTICLE | doi:10.20944/preprints202310.0573.v1
Subject: Biology And Life Sciences, Life Sciences Keywords: microscopy; optical diffraction tomography; Raman spectroscopy; therapy-induced senescence; cell engulfing; vacuole; cancer; cell-in-cell
Online: 10 October 2023 (05:32:15 CEST)
Wild-type p53 cancer therapy-induced senescent cells frequently engulf and degrade neighboring ones inside a massive vacuole in their cytoplasm. After clearance of the internalized cell, the vacuole persists, seemingly empty, for several hours. Despite large vacuoles being associated with cell death, this process is known to confer a survival advantage to cancer engulfing cells, leading to therapy resistance and tumor relapse. Previous attempts to resolve the vacuolar structure and visualize their content using dyes were unsatisfying for lack of known targets and ineffective dye penetration and/or retain. Here, we overcame this problem by applying optical diffraction tomography and Raman spectroscopy to MCF7 doxorubicin-induced engulfing cells. We demonstrated a real ability of cell tomography and Raman to phenotype complex microstructures, such as cell-in-cells and vacuoles, and detect chemical species in extremely low concentrations within live cells in a completely label-free fashion. We show that vacuoles had a density indistinguishable to the medium, but were not empty, instead contained diluted cell-derived macromolecules, and we could discern vacuoles from medium and cells using their Raman fingerprint. Our approach is useful for the non-invasive investigation of senescent engulfing (and other peculiar) cells in unperturbed conditions, crucial for a better understanding of complex biological processes.
ARTICLE | doi:10.20944/preprints202002.0364.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Glioblastoma Multiforme; rat model; NK-Cell Therapy; MRI Cell traking; Fouresecent cell tracking; blood brain barrier
Online: 25 February 2020 (06:51:39 CET)
Natural killer (NK) cell therapy is one of the most promising treatments for Glioblastoma Multiforme (GBM). However, this emerging technology is limited by the availability of sufficient numbers of fully functional cells. Here, we investigated the efficacy of NK cells that were expanded and treated by interleukin-2 (IL-2) and heat shock protein70 (HSP70), both in vitro and in vivo. Proliferation and cytotoxicity assays were used to assess the functionality of NK cells in vitro, after which treated and naïve NK cells were administrated intra-cranially and systemically to compare the potential antitumor activities in our in vivo rat GBM models. In vitro assays provided strong evidence of NK cell efficacy against C6 tumor cells. In vivo tracking of NK cells showed efficient homing around and within the tumor site. Furthermore, significant amelioration of the tumor in rats treated with HSP70/Il-2 treated NK cells as compared to those subjected to non-treated NK cells, as confirmed by MRI, proved the efficacy of adoptive NK cell therapy. Moreover, results obtained with systemic injection confirmed migration of activated NK cells over the blood brain barrier and subsequent targeting of GBM tumor cells. Our data suggest that administration of HSP70/Il-2 treated NK cells may be a promising therapeutic approach to be considered in the treatment of GBM.
ARTICLE | doi:10.20944/preprints202102.0123.v1
Online: 3 February 2021 (16:05:57 CET)
Metal-supported fuel cells (MSCs) offer potential material cost and robustness advantage over anode supported cells (ASCs). Because of the very good thermal shock stability of such MSCs, these can be heated up very quickly. However the challenge co-firing of metal substrate and electrolyte stays still unsolved. The production of the core component, the tape casted metal substrate, with defined shrinkage resulting from modification of metal powders is presented in the paper. This approach leads to an adjustment of the shrinkage mismatch during sintering, between metal and ceramic components, and adjustment of target specifications like porosity, green density and layer thickness.
ARTICLE | doi:10.20944/preprints202305.0154.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: cell-cell interaction; emerging yeasts; drug-resistance; virulence; physicochemical conditions
Online: 3 May 2023 (12:56:06 CEST)
The multidrug-resistant fungal pathogens belonging to the Candida haemulonii complex and the phylogenetically related species Candida auris are well-known for causing infections that are difficult to treat due to their multidrug-resistance profile. C. auris is even more worrisome due to its ability to cause outbreaks in healthcare settings. These emerging yeasts produce a wide range of virulence factors that facilitate the development of the infectious process. In recent years, the aggregative phenotype has been receiving attention, as it is mainly associated with defects in cellular division and its possible involvement in helping the fungus to escape from host immune responses. In this study, we initially investigated the aggregation ability of 18 clinical isolates belonging to the C. haemulonii species complex and C. auris. Subsequently, we evaluated the effects of physicochemical factors on the fungal aggregation competence. The results demonstrated that cell aggregation was a typically time-dependent event, in which almost all studied fungal isolates exhibited high aggregation after 2 h of incubation at 37°C. The aggregation was not impacted by pH, temperature, -mercaptoethanol (a protein-denaturing agent) and EDTA (a chelator agent). Conversely, proteinase K, trypsin and sodium dodecyl sulfate significantly diminished the aggregation. Collectively, our results demonstrated that the aggregation ability in these opportunistic yeast pathogens is time-dependent, and surface proteins and hydrophobic interactions seem to mediate cell aggregation, since the presence of proteases and anionic detergent affected the aggregation ability. However, further studies are necessary to better elucidate this phenomenon.
REVIEW | doi:10.20944/preprints202301.0264.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: mitochondrial cell death; autophagy cell death; lipidomic analysis; drug development
Online: 16 January 2023 (03:37:34 CET)
Different studies corroborate a role for ceramide synthases and their downstream products, ceramides, in modulation of apoptosis and autophagy in the context of cancer. These mechanisms of regulation, however, appear to be context dependent in terms of ceramides’ fatty acid chain length, subcellular localization, and the presence or absence of their downstream targets. Our current understanding of the role of ceramide synthases and ceramides in regulation of apoptosis and autophagy could be harnessed to pioneer the development of new treatments to activate or inhibit a single type of ceramide synthase, thereby regulating the apoptosis induction or cross talk of apoptosis and autophagy in cancer cells. Moreover, the apoptotic function of ceramide suggests that ceramide analogues can pave the way for the development of novel cancer treatments. Therefore, in the current review paper we discuss the impact of ceramide synthases and ceramides in regulation of apoptosis and autophagy in context of different types of cancers. We also briefly introduce the latest methods to analyze the lipids in biological samples. Finally, we discuss the drug development strategies focusing on the ceramide synthases and ceramides as future therapeutic approaches in cancer therapy.
ARTICLE | doi:10.20944/preprints202206.0336.v1
Subject: Biology And Life Sciences, Agricultural Science And Agronomy Keywords: apple; fruit size; fruit development; cell division; cell expansion; ripening
Online: 24 June 2022 (09:46:09 CEST)
Apple (Malus x domestica) fruit size is dependent on cell division and cell expansion, processes which are subsequently regulated by plant hormones such as auxins, gibberellins, and cytokinins. In this study, we investigated the role of cell division and cell expansion in apple growth and identified which of the two was more deterministic to final fruit size. Three cultivars of different sizes were selected, namely, ‘Twenty Ounce’ (large-sized), ‘Royal Gala’ (medium-sized), and ‘Crabapple’ (small-sized). Gene expression and cell size analyses were conducted over the course of two consecutive seasons. The expression patterns of three classes of genes were markedly similar across all cultivars. Two cell division markers, namely, MdCDKB2;2 and MdANT2, were discovered to be correlatively expressed as both displayed initially high expression levels, which gradually declined from the early to late stages of growth time course. For cell expansion markers, MdEXP3 was upregulated as the cells expanded, while MdARF106 was expressed in both the cell division and expansion stages. Meanwhile, the ripening related gene MdACO1 was expectedly expressed only during the ending stages associated with ripening. Interestingly, the cell measurements taken regularly from each cultivar throughout the same eperimental timespan showed that cell sizes were unaltered and remained constant from initial pollination at the zeroth Days After Pollination (DAP), to ripening at 120 Days After Full Bloom (DAFB).
REVIEW | doi:10.20944/preprints202206.0103.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: cell death; death receptors; viral infection; signaling; regulated cell death
Online: 7 June 2022 (10:09:11 CEST)
The fate of a viral infection in the host begins with various types of cellular responses, such as abortive, productive, latent, and destructive infections. Apoptosis, necroptosis, and pyroptosis are the three major types of regulated cell death mechanisms that play critical roles in viral infection response. Cell shrinkage, nuclear condensation, bleb formation, and retained membrane integrity are all signs of osmotic imbalance-driven cytoplasmic swelling and early membrane damage in necroptosis and pyroptosis. Caspase-driven apoptotic cell demise is considered in many circum-stances as an anti-inflammatory, and some pathogens hijack the cell death signaling routes to initiate a targeted attack against the host. In this review, we selected mechanisms by which viruses interfere with cell death are discussed in-depth and are used to illustrate the general principles and cellular signaling mechanisms of virus-host specific molecule interactions.
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: Neural Stem Cell; Secretome; Neurodevelopment; Radial Glia; Neural Progenitor Cell
Online: 4 October 2021 (12:25:30 CEST)
Neural stem cell (NSC) based therapies are at the forefront of regenerative medicine strategies to combat illness and injury of the central nervous system (CNS). In addition to their ability to produce new cells, NSCs secrete a variety of products, known as the NSC secretome, that have been shown to ameliorate CNS disease pathology and promote recovery. As pre-clinical and clinical research to harness the NSC secretome for therapeutic purposes advances, a more thorough understanding of the endogenous NSC secretome can provide useful insight into the functional capabilities of NSCs. In this review, we focus on research investigating the autocrine and paracrine functions of the endogenous NSC secretome across life. We also compare the NSC secretome across species, finding signs of conserved parallels between rodent, human and zebrafish NSC secretomes. Throughout development and adulthood, we find evidence that the NSC secretome is a critical component of how endogenous NSCs regulate themselves and their niche. We also find gaps in current literature, most notably in the clinically relevant domain of endogenous NSC paracrine function in the injured CNS. Future investigations to further define the endogenous NSC secretome and its role in CNS tissue regulation are necessary to bolster our understanding of NSC-niche interactions and to aid in the generation of safe and effective NSC-based therapies.
REVIEW | doi:10.20944/preprints202108.0406.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: superantigen; T-cell; B-cell; cytokine storm; interface; antibody purification
Online: 19 August 2021 (19:25:42 CEST)
Superantigens are unconventional antigens which recognise immune receptors outside the usual binding sites e.g. complementary determining regions (CDRs), to elicit a response within the target cell. T-cell superantigens crosslink T-cell receptors and MHC Class II molecules on antigen-presenting cells, leading to lymphocyte recruitment, induction of cytokine storms and T-cell anergy or apoptosis among many other effects. B-cell superantigens, on the other hand, bind immunoglobulin receptors on B-cells affecting opsonisation, IgG-mediated phagocytosis, and drive B-cells into apoptosis. Here, through a review of the structural basis for recognition of immune receptors by superantigens, we show that their binding interfaces share specific physicochemical characteristics when compared with other protein-protein interaction complexes. Given that antibody-binding superantigens have been exploited extensively in industrial antibody purification, these observations could facilitate further protein engineering to optimize the use of superantigens in this and other areas of biotechnology.
REVIEW | doi:10.20944/preprints202107.0320.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Cell-cell fusion; henipavirus; pathogenesis; paramyxovirus; syncytium; within-host dynamics
Online: 14 July 2021 (11:09:08 CEST)
Syncytium formation, i.e., cell-cell fusion resulting in the formation of multinucleated cells, is a hallmark of infection by paramyxoviruses and other important viruses. This natural mechanism has historically been a diagnostic marker for paramyxovirus infection in vivo and is now widely studied for virus-induced membrane fusion in vitro. However, the role of syncytium formation in within-host dissemination and pathogenicity of viruses remains poorly understood. The diversity of henipaviruses and their wide host range and tissue tropism make them particularly appropriate models to characterize the drivers of syncytium formation and its implications for virus fitness and pathogenicity. Based on the henipavirus literature, we summarized current knowledge on the mechanisms driving syncytium formation, mostly acquired from in vitro studies, and on the in vivo distribution of syncytia. While these data suggest that syncytium formation widely occurs across henipaviruses, hosts and tissues, we identified important data gaps that undermined our understanding of the role of syncytium formation in virus pathogenesis. Based on these observations, we propose solutions of varying complexity to fill these data gaps, from better practices in data archiving and publication for in vivo studies, to experimental approaches in vitro.
ARTICLE | doi:10.20944/preprints202106.0506.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Cell main spectra; Circulating tumour cell; MALDI-TOF; Method development
Online: 21 June 2021 (11:31:02 CEST)
Circulating atypical cells (CAC) are released from a primary tumour site into peripheral blood and are indicators of cancer metastasis. CAC occur at very low frequency in circulating blood, and their detection remains challenging. Moreover, white blood cells (WBC) are the major contaminant in enriched CAC samples. Here, we developed matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) as a novel CAC characterization platform. Main spectra profiles (MSP) of normal and cancer cells were generated by MALDI-TOF MS, and a cell-main spectra database was then compiled and analysed using the MALDI Biotyper software. Logarithmic scores accurately predicted distinct cell types. The feasibility of this workflow was then validated using simulated samples, which were prepared by 5,000 WBC of three healthy individuals spiked with varying numbers (3, 6, 12, 25, 50 and 100) of lung, colon, or prostate cancer cells. MALDI-TOF MS was able to detect cancer cells down to six cells over the background noise of 5,000 WBC with significantly higher predictive scores as compared to WBC alone. Further development of cell-MSP database to cover all cancer types sourced from cell lines and patient tumours may enable the use of MALDI-TOF MS as a cancer-screening platform in clinical settings in the future.
ARTICLE | doi:10.20944/preprints202105.0418.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: pancreas tissue slices; acetylcholine; beta cell; acinar cell; Ca2+ oscillations
Online: 18 May 2021 (11:03:59 CEST)
Cholinergic innervation in pancreas controls both the release of digestive enzymes to support the intestinal digestion and absorption, as well as insulin release to promote nutrient use in the cells of the body. The effects of muscarinic receptor stimulation are described in detail for endocrine beta cells and exocrine acinar cells separately. Here we describe morphological and functional criteria to separate these two cell types in situ in tissue slices and simultaneously measure their response to ACh stimulation on cytosolic Ca2+ oscillations [Ca2+]c in stimulatory glucose conditions. Our results show that both cell types respond to glucose directly in the concentration range compatible with the glucose transporters they express. The physiological ACh concentration increases the frequency of glucose stimulated [Ca2+]c oscillations in both cell types and synchronizes [Ca2+]c oscillations in acinar cells. The pharmacological ACh concentration further increases the oscillation frequency on the level of individual beta cells, inhibits the synchronization between these cells, and abolishes oscillatory activity in acinar cells. We discuss possible mechanisms leading to the observed phenomena.
ARTICLE | doi:10.20944/preprints202009.0280.v1
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: MDS; immune cell repertoire; prognosis; multiplex immunohistochemistry; stem cell niche
Online: 13 September 2020 (11:51:13 CEST)
Purpose: Myelodysplastic syndromes (MDS) are caused by a stem cell failure, but the relationship between immune dysregulation and the course of disease has not yet been analyzed in detail. Experimental design: To get insights into the pathophysiologic and clinical relevance of the histotopography of immune cell subpopulations in this process, the immune cell infiltrate with focus on its spatial distribution was determined by multispectral imaging (MSI) in 147 bone marrow biopsies from MDS or secondary acute myeloid leukemia (sAML) patients and healthy controls (HC). In addition, the data were correlated to genetic alterations and clinical features of these patients including therapy response. Results: A high inter-tumoral heterogeneity in the frequency and spatial distribution of CD3+CD8+, CD3+CD8-, CD3+FOXP3+ T cell subsets, MUM1p+CD3- post-germinal B/plasma cells and CD34+ blasts was found in MDS and sAML samples. In HC only few B cells/plasma cells, but no T cell subpopulations were detected in the proximity to CD34+ blasts. In contrast, the frequency of these lymphocytes was increased in proximity to CD34+ blasts in both MDS and sAML independent of the karyotype, genetic alterations frequently detected in MDS, clinical risk stratification systems or treatment response to hypomethylating agents. Furthermore, an increased frequency of CD3+CD8+ T cells and MUM1p+ CD3- B cells was found in responders to epigenetic drugs. Conclusions: Thus, we conclude that (i) T cell subsets do not belong to the normal stem cell niche, (ii) the presence of T and B cell subpopulations not directly affect the course of MDS, (iii) lymphocytes in the proximity to CD34+ blasts might indicate defective stem cell properties and (iv) the number of lymphocytes is a predictor of therapy response to hypomethylating agents.
REVIEW | doi:10.20944/preprints202003.0461.v2
Subject: Engineering, Bioengineering Keywords: cell free protein synthesis; cell free metabolic engineering; metabolic modeling
Online: 30 April 2020 (05:19:00 CEST)
Cell free systems are a widely used research tool in systems and synthetic biology and a promising platform for manufacturing of proteins and chemicals. In the past, cell free biology was primarily used to better understand fundamental biochemical processes. Notably, E. coli cell free extracts were used in the 1960s to decipher the sequencing of the genetic code. Since then, the transcription and translation capabilities of cell free systems have been repeatedly optimized to improve energy efficiency and protein yield. Today, cell free systems, in combination with the rise of synthetic biology, have taken on a new role as a promising technology for just in time manufacturing of therapeutically important biologics and high-value small molecules. They have also been implemented in an industrial scale for the production of antibodies and cytokines. In this review, we discuss the evolution of cell free systems, advancements in cell free protein synthesis, and cell free metabolic engineering, and conclude with discussing the importance and feasibility of mathematical modeling in cell free systems.
REVIEW | doi:10.20944/preprints202003.0228.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Immunogenic cell death; DAMPs; cell death resistance; immunotherapy; combination therapy
Online: 13 March 2020 (10:04:56 CET)
Cell death resistance is a key feature of tumor cells. One of the main anti-cancer therapies is increasing the susceptibility of cells to death. Cancer cells have developed a capability of tumor immune escape. Hence, restoring the immunogenicity of cancer cells can be suggested as an effective approach against cancer. Accumulating evidence proposes that several anticancer agents provoke the release of danger-associated molecular patterns (DAMPs) that are determinants of immunogenicity and stimulate immunogenic cell death (ICD). It has been suggested that ICD inducers are two different types according to their various activities. Here, we review the well-characterized DAMPs and focus on the different types of ICD inducers and recent combination therapies that can augment the immunogenicity of cancer cells.
REVIEW | doi:10.20944/preprints201812.0333.v1
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: gap junction; connexin; angiogenesis; cell mechanics; cell migration; cellular stiffness
Online: 28 December 2018 (05:19:52 CET)
Angiogenesis, the sprout and growth of new blood vessels from existing vasculature, is an important process of tumor development for the supply of oxygen and nutrition to cancer cells. Endothelial cell is a critical player in angiogenic process by modulating cell proliferation, cell motility, and cell morphology in the response to pro-angiogenic factors and environments provided by tumor and cancer cells. Recent in vivo and in vitro studies have revealed that gap junction of endothelial cells also participates in the promotion of angiogenesis. Pro-angiogenic factors modulate gap junction function and connexins expression in endothelial cells, whereas endothelial connexins involve in angiogenic tube formation and cell migration of endothelial cells via both gap junction channel function dependent or independent mechanisms. In particular, connexin might have the potential to regulate cell mechanics such as cell morphology, cell migration, and cellular stiffness that are dynamically changed during angiogenic processes. Here, we review the implication for endothelial gap junction and cellular mechanics in vascular angiogenesis.
ARTICLE | doi:10.20944/preprints201810.0121.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: SAHA; RG7388; MDM2; p53; p21; cell cycle arrest; cell death
Online: 7 October 2018 (11:33:18 CEST)
Alterations in gene expressions are often due to epigenetic modifications that can lead to significant influence on cancer development, growth, and progression. The main epigenetic modifications observed in human are methylation and acetylation. In this regard, the HDAC inhibitors (HDACi) such as SAHA (Vorinostat), which can exert epigenetic alterations through impacting the acetylation status of histones, are in clinical trials as a new class of drugs with promising effects on the cancer growth and metastatic process. The small molecule RG7388 is a newly developed inhibitor that is specific for an oncogene-derived protein called MDM2, which is in clinical trials for the treatment of various types of cancers. One of the common characteristics for these two drugs is their ability to induce p21 expression through distinct mechanisms in MCF-7 and LNCaP cells. This difference was expected trigger cell cycle arrest and cell death through intra-cellular mechanisms that are not identical. Hence, the molecular mechanism whereby SAHA can induce cell cycle arrest and trigger necrosis, apoptosis or necroptosis is still evolving. Similarly, the ability of RG7388 for producing anticancer effect is undergoing thorough investigation, since it can produce p53 dependent and p53 independent effects. In this study we performed experiments to measure the cell cycle arrest effects of SAHA and RG7388 on using MCF-7 and LNCaP cells. The cytotoxicity, cell cycle arrest and apoptosis/necroptosis effects of the treatments were assessed by using Trypan Blue Dye Exclusion (TBDE) method, MTT assay, Fluorescence assay with DEVD-amc fluorogenic substrate and Immunoblotting methods. Our results from MCF-7 and LNCaP cells confirmed that SAHA and RG7388 treatments were able to induce cell death via combination of cell cycle arrest and cytotoxic mechanisms. We are speculating that our findings could lead to the development of newer treatments for breast and prostate cancers using this type of combinations.
ARTICLE | doi:10.20944/preprints201801.0037.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: Emdogain; amelogenin; dental pulp cells; cell differentiation; cell migration; mineralization
Online: 7 January 2018 (11:00:15 CET)
Enamel matrix derivative (EMD) is used for periodontal tissue regeneration therapy, and can induce mineralization in dental pulp cells (DPCs). We designed a synthetic peptide (SP) derived from the response of cells to EMD, and investigated the effect of the SP on potentiating osteogenesis in DPCs, which have a critical role of dental pulp homeostasis. DPCs were treated with 0, 10, 100, or 1000 ng/mL SP to determine its effect on cell proliferation, cell migration, cell differentiation, and mineralization. We then examined the molecular effects of the SP, focusing on changes in the mitogen-activated protein kinases (MAPK) signaling pathway in these cells. The SP significantly promoted DPC proliferation and migration. Cultures treated with the SP also showed an enhanced expression of markers of osteogenic differentiation and mineralization. The SP also induced the activation of MAPK signaling pathway components. These results suggest that our SP could promote the dental pulp tissue repair by hard tissue formation and the mineralization through activating MAPK signaling pathway. This study provides the first evidence that SP might be a new material for dental pulp tissue treatment.
ARTICLE | doi:10.20944/preprints201611.0051.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: angiogenesis; cell invasion; cell migration; Flavone derivative (TTF1); hepatoma; STAT3
Online: 9 November 2016 (10:21:43 CET)
TTF1-NP(5,2′,4′-trihydroxy-6,7,5′-trimethoxyflavone nanoparticles), derived from the traditional Changbai Mountain medicinal plant Sorbaria sorbifolia (SS), has been showedits anti-cancer effect in various liver cancer cell types and tissues. The present study was designed to evaluate the antitumor mechanism of the TTF1-NP against HepG2 hepatoma cells and HepG2 cells-induced hepatocarcinoma (HCC) in nude mouse model. Here we demonstrated that TTF1-NP inhibits tube formation of HUVECs and HepG2 cell migration and invasion, and inhibits tumor growth in nude mice implanted with HepG2 cells through the downregulation of STAT3 protein and activation, along with VEGF, KDR, bFGF, MMP2 and MMP9 levels. We further revealed that TTF1-NP decreased the DNA-binding capacity of STAT3. Together our results provide a mechanism by which TTF1-NP suppresses cancer cell migration, invasion and angiogenesis through the action of STAT3 and suggests TTF1-NP as a potential therapy for hepatocellular cancer treatment.
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: NK cell biology; NK cell subsets; NK activating receptors; cell adhesion molecules; granule polarization; cytotoxicity assay; cis interactions; trogocytosis; NK cell degranulation; NK-Based Immunotherapies
Online: 14 February 2020 (03:13:05 CET)
NK population is characterized by distinct NK cell subsets which respond differently to the various activating stimuli. For this reason, the determination of the optimal cytotoxic activation of the different NK subsets can be a crucial aspect to be exploited to counter cancer cells in oncologic patients. To evaluate how the triggering of different combination of activating receptors can affect the cytotoxic responses of different NK cell subsets, we developed a microbead-based degranulation assay. By using this new assay, we were able to detect CD107a+ degranulating NK cells even within the less cytotoxic subsets (i.e. resting CD56bright and unlicensed CD56dim NK cells), thus demonstrating its high sensitivity. Interestingly, signals delivered by the co-engagement of NKp46 with 2B4, but not with CD2 or DNAM-1, strongly cooperate to enhance degranulation on both licensed and unlicensed CD56dim NK cells. Of note, 2B4 is known to bind CD48 hematopoietic antigen, therefore this observation may provide the rationale why CD56dim subset expansion correlates with successful hematopoietic stem cell transplantation mediated by alloreactive NK cells against host T, DC and leukemic cells, while sparing host non-hematopoietic tissues and graft versus host disease. The assay further confirms that activation of LFA-1 on NK cells leads to their granule polarization, even if, in some cases, this also takes to an inhibition of NK degranulation, suggesting that LFA-1 engagement by ICAMs on target cells may differently affect NK cell response. Finally, we observed that NK cells undergo a time-dependent spontaneous (cytokine-independent) activation after blood withdrawal, an aspect that may strongly bias the evaluation of the resting NK cell response. Altogether our data may pave the way to develop new NK activation and expansion strategies that target the highly cytotoxic CD56dim NK cells and can be feasible and useful for cancer and viral infection treatment.
REVIEW | doi:10.20944/preprints202108.0453.v1
Subject: Biology And Life Sciences, Biophysics Keywords: Hybrid epithelial/mesenchymal phenotypes; Collective cell migration; epithelial-mesenchymal heterogeneity; mathematical modeling; cell-state transition; live-cell imaging
Online: 23 August 2021 (14:32:04 CEST)
The Epithelial- Mesenchymal Transition (EMT) is a biological phenomenon associated with explicit phenotypic and molecular changes in cellular traits. Unlike the earlier-held popular belief of it being a binary process, EMT is now thought of as a landscape including diverse hybrid E/M phenotypes manifested by varying degrees of the transition. These hybrid cells can co-express both epithelial and mesenchymal markers and/or functional traits, and can possess the property of collective cell migration, enhanced tumor-initiating ability, and immune/targeted therapy-evasive features, all of which are often associated with worse patient outcomes. These characteristics of the hybrid E/M cells have led to a surge in studies that map their biophysical and biochemical hallmarks that can be helpful in exploiting their therapeutic vulnerabilities. This review discusses recent advances made in investigating hybrid E/M phenotype(s) from diverse biophysical and biochemical aspects by integrating live cell-imaging, cellular morphology quantification and mathematical modeling, and highlights a set of questions that remain unanswered about the dynamics of hybrid E/M states.
ARTICLE | doi:10.20944/preprints202009.0192.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: connexin 43; gap junctions; cancer; intercellular communication; breast cancer; cell signaling; tunneling nanotubes; cell–cell communication; tumor microtubes
Online: 9 September 2020 (03:09:50 CEST)
Connexin 43 (Cx43) forms gap junctions that mediate the direct intercellular diffusion of ions and small molecules between adjacent cells. Cx43 displays both pro- and anti-tumorigenic properties, but the mechanisms underlying these characteristics are not fully understood. Tunneling nanotubes (TNTs) are long and thin membrane projections that connect cells, facilitating the exchange of not only small molecules, but also larger proteins, organelles, bacteria, and viruses. Typically, TNTs exhibit increased formation under conditions of cellular stress and are more prominent in cancer cells, where they are generally thought to be pro-metastatic and to provide growth and survival advantages. Cx43 has been described in TNTs, where it is thought to regulate small molecule diffusion through gap junctions. Here, we developed a high-fidelity CRISPR/Cas9 system to knockout (KO) Cx43. We found that loss of Cx43 expression was associated with significantly reduced TNT length and number in breast cancer cell lines. Notably, secreted factors present in conditioned medium stimulated TNTs more potently when derived from Cx43-expressing cells than from KO cells. Moreover, TNT formation was significantly induced by inhibition of several key cancer signaling pathways that both regulate Cx43 and are regulated by Cx43, including RhoA kinase (ROCK), protein kinase A (PKA), focal adhesion kinase (FAK), and p38. Intriguingly, drug-induced stimulation of TNTs was more potent in Cx43 KO cells than in wild-type cells. In conclusion, this work describes a novel non-canonical role for Cx43 in regulating TNTs, identifies key cancer signaling pathways that regulate TNTs in this setting, and provides mechanistic insight into a pro-tumorigenic role of Cx43 in cancer.
ARTICLE | doi:10.20944/preprints202305.1500.v1
Subject: Medicine And Pharmacology, Hematology Keywords: diffuse large B-cell lymphoma; relapsed; refractory; autologous stem cell transplantation
Online: 22 May 2023 (10:29:20 CEST)
Treating relapsed and refractory diffuse large B-cell lymphoma is still challenging for clinicians, but the available CAR-T and bispecific antibodies revolutionized therapy. Autologous stem cell transplantation was the most effective treatment modality previously. The authors report data from a single center over ten years. The retrospective study included 116 patients. There were 53 relapsed, 39 primary refractory cases, 19 had CNS involvement, and 5 received primary consolidation transplants. The median duration of follow-up was 46 months. The median event-free survival was 75 months, and the median overall survival was 105 months for all cases. Five-year overall survival was 59%, and event-free survival was 54%. Pretreatment prognostic factors at diagnosis had no effect on the outcome of transplantation. The authors found no difference between survival in relapsed or refractory cases, and the number of salvage lines or the germinal center / activated B-cell type also did not influence the results. Complete metabolic response before transplant confirmed by 18FDG PET/CT strongly affected survival. The pretransplant creatinine and CRP levels significantly influenced the long-term outcome. The number of stem cells infused did not affect survival, but engraftment within nine days did result in better survival. These data support the finding that the response to salvage therapy did select a better prognostic group who may still benefit from autologous transplantation.
ARTICLE | doi:10.20944/preprints202303.0007.v1
Subject: Biology And Life Sciences, Virology Keywords: Human herpesvirus 5; glycoprotein B; UL55; cell-cell fusion; entry; infectivity
Online: 1 March 2023 (03:05:22 CET)
Viruses can induce the fusion of infected and neighboring cells, leading to the formation of syncytia. Cell-cell fusion is mediated by viral fusion proteins on the plasma membrane of infected cells that interact with cellular receptors on neighboring cells. Viruses use this mechanism to spread rapidly to adjacent cells or escape host immunity. For some viruses, syncytium formation is a hallmark of infection and a known pathogenicity factor. For others, the role of syncytium formation in viral dissemination and pathogenicity remains poorly understood. Human cytomegalovirus (HCMV) is an important cause of morbidity and mortality in transplant patients and the leading cause of congenital infections. Clinical HCMV isolates have broad cell tropism but differ in their ability to induce cell-cell fusions, and little is known about the molecular determinants. We developed a system to analyze HCMV glycoprotein B (gB) variants in a defined genetic background. HCMV strains TB40/E and TR were used as vectors to compare the fusogenicity of six gB variants from congenitally infected fetuses with those from three laboratory strains. Five of them conferred the ability to induce fusion of MRC-5 human embryonic lung fibroblasts to one or both backbone strains, as determined by a split GFP-luciferase reporter system. The same gB variants were not sufficient to induce syncytia in infected ARPE-19 epithelial cells, suggesting that additional factors are involved. The system described here allows a systematic comparison of the fusogenicity of viral envelope glycoproteins and may help to clarify whether fusion-promoting variants are associated with increased pathogenicity.
ARTICLE | doi:10.20944/preprints202208.0364.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: TMPyP4 1; Thymoquinone 2; cell viability 3; cell adhesion 4; telomerase
Online: 19 August 2022 (10:46:07 CEST)
G‐quadruplexes (G4) are structures formed at the ends of the telomere, these are rich in guanines and were stabilized by molecules that bind to specific sites. TMPyP4 and Thymoquinone (TQ) are small molecules that bind to the G4, they have drawn attention because of their role as telomerase inhibitors. The aim of this study was to evaluate the effects of telomerase inhibitors on cellular proliferation, senescence, and death. Two cell lines LC‐HK2 (NSCLC) and RPE‐1 were treated with TMPyP4 (5μM) and TQ (10μM). Both inhibitors were effective in decreasing telomerase activity. TMPyP4 increased the percentage of cells with membrane damage associated with cell death and decreased the frequency of cells in the S‐phase. TMPyP4 changed the cell adhesion ability and modified the pattern of focal adhesion. TQ acted in a dose‐dependent manner, increasing the frequency of senescent cells, and inducing cell cycle arrest in the G1. In conclusion, the effects of both drugs on LC-HK2 and RPE-1 cell lines were different although both are telomerase inhibitors, because TMPyP4 decreased proteins of cell adhesion and TQ induces a decrease in cell viability.
ARTICLE | doi:10.20944/preprints202204.0307.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: receptors; extracellular DNA; cell-surface bound DNA; cell-surface bound RNA
Online: 29 April 2022 (15:04:38 CEST)
Here, our data provide the first evidence for the existence of a previously unknown receptive system formed by novel DNA- and RNA-based receptors in eukaryotes. This system, named the TR-system, is capable of recognizing and generating a response to different environmental factors and has been shown to orchestrate major vital functions of fungi, mammalian cells, and plants.Recently, we discovered the existence of a similar regulatory system in prokaryotes. These DNA- and RNA-based receptors are localized outside of the membrane forming a type of a network around cells that respond to a variety of chemical, biological, and physical factors and enabled the TR-system to regulate major aspects of eukaryotic cell life as follows: growth, including reproduction and development of multicellular structures; sensitivity to temperature, geomagnetic field, UV, light, and hormones; interaction with viruses; gene expression, recognition and utilization of nutrients. The TR-system was also implicated in cell memory formation and was determined to be responsible for its maintenance and the forgetting of preceding events. This system is the most distant receptive and regulatory system of the cell that regulates interactions with the outer environment and governs the functions of other receptor-mediated signaling pathways.
ARTICLE | doi:10.20944/preprints202109.0504.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: single cell RNAseq; single cell ATACseq; sparsely connected autoencoder; pseudo-bulk
Online: 29 September 2021 (17:26:18 CEST)
Background: Biological processes are based on complex networks of cells and molecules. Single cell multi-OMICs is a new tool aiming to provide new incites in the complex network of events controlling the functionality of the cell.; Methods: Since single cell technologies provide many sample measurements, they are the ideal environment for the application of deep learning and machine learning approaches. An autoencoder (AE) is composed of an encoder and a decoder sub-model. AE are very powerful in data compression and noise removal. However, the decoder model remains a black box from which is impossible to depict the contribution of the single input elements. We have recently developed a new class of autoencoders, called Sparsely Connected Autoencoders (SCA), which have the advantage of providing a controlled association among the input layer and the decoder module. This new architecture has the benefit that the decoder model is no anymore a black box and it can be used to depict new biologically interesting features from single cell data; Results: In this paper, we show that SCA hidden layer can grab new information usually hidden in single cell data, like as providing clustering on meta-features difficult, i.e. transcription factors expression, or impossible, miRNA expression, to depict in single cell RNAseq data. Furthermore, a SCA representation of cell clusters has the advantage of simulating a conventional bulk RNAseq, which is a data transformation allowing the identification of similarity among independent experiments; Conclusions: In our opinion, SCA represent the bioinformatics version of a “Swiss Army knife” for the extraction of hidden knowledgeable features from single cell OMICs data.
REVIEW | doi:10.20944/preprints202108.0518.v2
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: liquid biopsy; circulating biomarkers; Alzheimer’s disease; neurodegeneration; cell-free; diagnosis
Online: 8 March 2022 (09:56:01 CET)
Alzheimer’s disease is the most common neurodegenerative disease and affects persons of all races, ethnic groups, and sexes. The disease is characterized by neuronal loss leading to cognitive decline and memory loss. There is no cure and the effectiveness of existing treatments is limited and depends on the time of diagnosis. The long prodromal period, during which patients’ ability to live a normal life is not affected despite neuronal loss, often leads to a delayed diagnosis because it can be mistaken for normal aging of the brain. In order to make a substantial impact on AD patients, early diagnosis may provide a greater therapeutic window for future therapies to slow AD-associated neurodegeneration. Current gold standards for disease detection include magnetic resonance imaging and positron emission tomography scans, which visualize amyloid β and phosphorylated tau depositions and aggregates. Liquid biopsies, already an active field of research in precision oncology, are hypothesized to provide early disease detection through minimally or non-invasive sample collection techniques. Liquid biopsies in Alzheimer’s disease have been studied in cerebrospinal fluid, blood, ocular, oral, and olfactory fluids. However, most of the focus has been on blood and cerebrospinal fluid due to biomarker specificity and sensitivity attributed to the effects of the blood-brain barrier and inter-laboratory variation during sample collection. Many studies have identified amyloid β and phosphorylated tau levels as putative biomarkers, however, advances in next-generation sequencing-based liquid biopsy methods have led to significant interest in identifying nucleic acids species associated with Alzheimer’s disease from liquid tissues. Differences in cell-free RNAs and DNAs have been described as potential biomarkers for AD and hold the potential to affect disease diagnosis, treatment, and future research avenues.
REVIEW | doi:10.20944/preprints202105.0730.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: intrauterine growth restriction (IUGR); metabolism; cell stress; cell death; metabolic syndrome
Online: 31 May 2021 (10:19:23 CEST)
Disruption of the in utero environment can have dire consequences on fetal growth and development. Intrauterine growth restriction (IUGR) is a pathological condition by which the fetus deviates from its expected growth trajectory, resulting in low birth weight and impaired organ function. The developmental origins of health and disease (DOHaD) postulates that IUGR has lifelong consequences on offspring well-being, as human studies have established an inverse relationship between birth weight and long-term metabolic health. While these trends are apparent in epidemiological data, animal studies have been essential in defining the molecular mechanisms that contribute to this relationship. One such mechanism is cellular stress, a prominent underlying cause of the metabolic syndrome. As such, this review considers the role of oxidative stress, mitochondrial dysfunction, endoplasmic reticulum (ER) stress, and inflammation in the pathogenesis of metabolic disease in IUGR offspring. In addition, we summarize how uncontrolled cellular stress can lead to programmed cell death within the metabolic organs of IUGR offspring.
REVIEW | doi:10.20944/preprints202105.0217.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: stem cells; retinal diseases; optic nerve diseases; cell replacement; cell sources
Online: 10 May 2021 (15:34:07 CEST)
The aim of this review was to provide an update on the potential of cell therapies to restore or replace damaged and/or lost cells in retinal degenerative and optic nerve diseases, describing the available cell sources and the challenges involved in such treatments when these techniques are applied in real clinical practice. Sources include human fetal retinal stem cells, allogenic cadaveric human cells, adult hippocampal neural stem cells, human CNS stem cells, ciliary pigmented epithelial cells, limbal stem cells, retinal progenitor cells (RPCs), human pluripotent stem cells (PSCs) (including both human embryonic stem cells (ESCs) and human induced pluripotent stem cells (iPSCs)) and mesenchymal stem cells (MSCs). Of these, RPCs, PSCs and MSCs have already entered early-stage clinical trials since they can all differentiate into RPE, photoreceptors or ganglion cells, and have demonstrated safety, while showing some indicators of efficacy. Stem/progenitor cell therapies for retinal diseases still have some drawbacks, such as the inhibition of proliferation and/or differentiation in vitro (with the exception of RPE) and the limited long-term survival and functioning of grafts in vivo. Some other issues remain to be solved concerning the clinical translation of cell-based therapy, including (1) the ability to enrich for specific retinal subtypes; (2) cell survival; (3) cell delivery, which may need to incorporate a scaffold to induce correct cell polarization, which increases the size of the retinotomy in surgery and, therefore, the chance of severe complications; (4) the need to induce retinal detachment to perform the subretinal placement of the transplanted cell; and (5) the evaluation of the risk of tumor formation caused by the undifferentiated stem cells and prolific progenitor cells. Despite these challenges, stem/progenitor cells represent the most promising strategy for retinal and optic nerve disease treatment in the near future, and therapeutics assisted by gene techniques, neuroprotective compounds and artificial devices can be applied to fulfil clinical needs.
REVIEW | doi:10.20944/preprints202011.0034.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: cell signaling; signaling pathways; single-cell sequencing; immunotherapy; hallmarks cancer; cancer
Online: 2 November 2020 (11:28:51 CET)
Cancer is the second leading cause of death worldwide. It is theorized that underlying genetic and epigenetic changes enable cells to proliferate out of control by escaping regulatory mechanisms. Although traditional molecular profiling techniques, i.e., bulk sequencing, can identify common mutations and gene expression patterns in cancer cells, they cannot detect tumour heterogeneity. However, single-cell technology has provided an ample opportunity to overcome this difficulty. Since this technology allows us to detect the heterogeneous properties of all cancer cells, this can further our knowledge of the signaling pathways in cancer cells. Indeed, single-cell transcriptomics technology has paved the road for identifying novel biomarkers and signaling pathways, which can serve as targets. This study aims to review the current knowledge about pathways involved in developing cancer cells and shed light on single-cell studies as promising therapeutic approaches.
ARTICLE | doi:10.20944/preprints202007.0484.v1
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: Gastric cancer; Submucosal invasion; Intestinal stem cell; Cancer stem cell; Prognosis
Online: 21 July 2020 (12:34:02 CEST)
Submucosal invasion is a critical step in gastric cancer (GC) progression, which greatly enhances metastasis risk. Cancer stem cells are responsible for invasion, metastasis, and tumor growth. To identify stem cell-related markers associated with submucosal invasion in GCs, we investigated the expression of candidate cancer stem cell (CSC) markers (CD133, CD44, and ALDH1A) and intestinal stem cell (ISC) markers (EPHB2, OLFM4, and LGR5) in early GCs with submucosal invasion. Remarkably, expression of all ISC markers and CD133 was frequently confined to the basal area of the lamina propria (basal pattern) in mucosal cancer. The proportion of stem cell marker-positive cells substantially increased during submucosal invasion. Given that ISC markers are restricted to the crypt base of the normal intestinal mucosa, these findings suggest that many early GCs may retain hierarchical characteristics. CD44 expression showed a focal pattern, ALDH1A was predominantly expressed diffusely, and there was no expansion of CD44 or ALDH1A expression in the submucosal cancer cells. RSPO2 from muscularis mucosa seem to be partly responsible for the increased expression of ISC markers in GC cells at the basal areas. We also found that ISC markers were correlated with CDX2 expression in GCs, indicating that ISC markers are involved in the intestinal differentiation in GCs. Interestingly, ISC markers (EPHB2 and OLFM4) and CD133 showed a positive impact on clinical outcomes. In particular, the prognostic value of EPHB2 was significant for intestinal-type GCs in a multivariate analysis. In summary, ISC markers and CD133 showed a basal distribution pattern along with enhanced expression in submucosal invading cells in early GCs. EPHB2 was an independent prognostic marker in intestinal-type GCs.
ARTICLE | doi:10.20944/preprints201911.0177.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: macrophage migration inhibitory factor; HNSCC cell lines; proliferation; cell cycle; apoptosis
Online: 15 November 2019 (08:48:50 CET)
Macrophage migration inhibitory factor (MIF) is a multifunctional cytokine that contributes to the progression of several cancers. MIF overexpression has been reported in head and neck squamous cell carcinoma (HNSCC) patients. However, the exact role of MIF in HNSCC is not fully understood. Our aim was to evaluate the amount of secreted MIF and the role of MIF in the proliferation, cell cycle, and apoptosis in HNSCC cell lines. The MIF levels in conditioned media from human primary (HN18 and HN30) and metastatic (HN17 and HN31) HNSCC cell lines were evaluated using ELISA. The HNSCC cell lines were treated with recombinant MIF and its effect on proliferation, cell cycle, and apoptotic status was determined by MTT and flow cytometry, respectively. The HNSCC-secreted MIF concentration ranged from 49.33‒860 pg/ml. Exogenous MIF (25 ng/ml) significantly increased HN18, HN30, and HN31 cell proliferation. Moreover, MIF induced cell cycle progression and inhibited apoptosis in these cells. However, MIF did not affect growth or apoptosis in HN17 cell. In conclusion, the HNSCC cell lines were evaluated secrete MIF. Exogenous MIF promotes various effects on proliferation, cell cycle, and apoptosis in HNSCC cells.
REVIEW | doi:10.20944/preprints201909.0079.v1
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: Thromboangiitis Obliterans; inflammation; angiogenesis; immunomodulation; pluripotent stem cell; mesenchymal stem cell
Online: 7 September 2019 (00:31:05 CEST)
Buerger's disease or Thromboangiitis Obliterans (TAO) is a nonatherosclerotic segmental vascular disease which affects small and medium arteries and veins in the upper and lower extremities. Based on pathological findings, TAO can be considered as a distinct form of vasculitis that is most prevalent in young male smokers. There is no definitive cure for this disease as therapeutic modalities are limited in number and efficacy. Surgical bypass has limited utility and 24% of patients will ultimately require amputation. Recently, studies have shown that therapeutic angiogenesis and immunomodulatory approaches through the delivery of cells to target tissues are potential options for ischemic lesion treatment. In this review, we summarize the current knowledge of TAO treatment and provide an overview of stem cell-based treatment modalities.
ARTICLE | doi:10.20944/preprints201904.0264.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: human adipose stem cell; NANOG; cell cycle regulation; DNMT1; lentiviral transduction
Online: 24 April 2019 (10:45:01 CEST)
The core components of regenerative medicine are stem cells with high self-renewal and tissue regeneration potentials. Adult stem cells can be obtained from many organs and tissues. NANOG, SOX2 and OCT4 represent the core regulatory network that suppresses differentiation-associated genes, maintaining the pluripotency of mesenchymal stem cells. The roles of NANOG in maintaining self-renewal and undifferentiated status of adult stem cells are still not perfectly established. In this study we define the effects of downregulation of NANOG in maintaining self-renewal and undifferentiated state in mesenchymal stem cells (MSCs) derived from subcutaneous adipose tissue (hASCs). hASCs were expanded and transfected in vitro with short hairpin Lentivirus targeting NANOG. Gene suppressions were achieved at both transcript and proteome levels. The effect of NANOG knockdown on proliferation after 10 passages and on the cell cycle was evaluated by proliferation assay, colony forming unit (CFU), qRT-PCR and cell cycle analysis by flow-cytometry. Moreover, NANOG involvement in differentiation ability was evaluated. We report that downregulation of NANOG revealed a decrease in the proliferation and differentiation rate, inducing cell cycle arrest by increasing p27/CDKN1B (Cyclin-dependent kinase inhibitor 1B) and p21/CDKN1A(Cyclin-dependent kinase inhibitor 1A) through p53 and regulate DLK1/PREF1. Furthermore, NANOG induced downregulation of DNMT1, a major DNA methyltransferase responsible for maintaining methylation status during DNA replication probably involved in cell cycle regulation. Our study confirms that NANOG regulates the complex transcription network of plasticity of the cells, inducing cell cycle arrest and reducing differentiation potential.
REVIEW | doi:10.20944/preprints201811.0592.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: caspase-3; cell death; apoptosis; cell proliferation; neurons; glia; cerebellum; development
Online: 26 November 2018 (11:48:00 CET)
Caspase-3, onto which there is a convergence of the intrinsic and extrinsic apoptotic pathways, is the main executioner of apoptosis. We here review the current literature on the intervention of the protease in the execution of naturally occurring neuronal death (NOND) during cerebellar development. We will consider data on the most common altricial species (rat, mouse and rabbit), as well as humans. Among the different types of neurons and glia in cerebellum, there is ample evidence for an intervention of caspase-3 in the regulation of NOND of the post-mitotic cerebellar granule cells (CGCs) and Purkinje neurons as a consequence of failure to establish proper synaptic contacts with target (secondary cell death). It seems possible that also the GABAergic interneurons undergo a similar type of secondary cell death, but the intervention of caspase-3 in this case still remains to be clarified in full. Remarkably, CGCs also undergo primary cell death at the precursor/pre-migratory stage of differentiation, in this case without the intervention of caspase-3. Glial cells as well undergo a process of regulated cell death, but it seems possible that expression of caspase-3, at least in the Bergmann glia, is related to differentiation rather than death.
ARTICLE | doi:10.20944/preprints201809.0133.v1
Subject: Medicine And Pharmacology, Gastroenterology And Hepatology Keywords: cell migration; hepatic stellate cell; TGF-β1; Rap1; RhoA; NF-κB
Online: 7 September 2018 (12:19:49 CEST)
Although the migration of hepatic stellate cells (HSCs) is important for hepatic fibrosis, the regulation of HSC migration is poorly understood. Interestingly, transforming growth factor (TGF)-β1 induces monocyte migration to sites of injury or inflammation in the early phase but inhibits cell migration in the late phase. In this study, we investigated the role of RhoA signaling in TGF-β1-induced HSC migration. We found that TGF-β1 increased the protein and mRNA levels of α-SMA and collagen type I in HSC-T6 cells. The level of RhoA-GTP in TGF-β1-stimulated cells was significantly higher than that in control cells. Moreover, cofilin phosphorylation and F-actin formation was more strongly detected in TGF-β1-stimulated cells than in control cells. Additionally, TGF-β1 induced the activation of NF-κB and the expression of extracellular matrix proteins and several cytokines in HSC-T6 cells. The active form of Rap1 (Rap1 V12) suppressed RhoA-GTP levels, whereas the dominant negative form of Rap1 (Rap1 N17) augmented RhoA-GTP levels. Therefore, we confirmed that Rap1 regulates RhoA activation in TGF-β1-stimulated HSC-T6 cells. These findings suggest that TGF-β1 regulates Rap1, resulting in RhoA suppression, NF-κB activation and F-actin formation during the migration of HSCs.
ARTICLE | doi:10.20944/preprints201703.0162.v1
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: Particulate matter; BM-MSCs; cell proliferation; cell death; qRT-PCR; IPA
Online: 20 March 2017 (16:33:56 CET)
Particulate matter (PM) contains heavy metals that affect various cellular functions and gene expression associated with an array of acute and chronic diseases, in humans. However, their specific effects on the stem cells remain unclear. Here, we report the effects of PM collected from Jeddah city on bone marrow mesenchymal stem cells (BM-MSCs) on proliferation, cell death, related gene expression and systems biological analysis aiming to understand the underlying mechanisms. Two different sizes (PM2.5-10) were tested in vitro at various concentrations (15 to 300 µg/ml) and durations (24 to 72 h). PMs induced cellular stress including membrane damage, shrinkage and death. Lower concentrations of PM2.5 increased BM-MSCs proliferation, while higher concentrations decreased it. PM10 decreased BM-MSCs proliferation in a concentration-dependant manner. The X-Ray Fluorescence spectrometric analysis showed that PM contains high levels of heavy metals. Ingenuity Pathway Analysis (IPA) and hierarchical clustering analyses showed that heavy metals were associated with signalling pathways involving cell stress/death, cancer and chronic diseases. qRT-PCR results showed differential regulation of the apoptosis genes (BCL2, BAX); upregulation of inflammation associated genes (TNF-a and IL-6) and downregulation of cell cycle regulation gene (P53). We conclude that PM could affect different cellular functions and predispose to debilitating diseases.
ARTICLE | doi:10.20944/preprints202306.0608.v1
Online: 8 June 2023 (08:25:02 CEST)
The use of hydrogen fuel cells as a mobile source of electricity might prove to be a keystone in future decarbonization of heavy duty road and marine transport. Due to complex interplay of various physicochemical processes in the fuel cells, further development of these devices will rely on concerted effort of researchers from various fields, e.g. chemistry, physics, electric and mechanical engineering. This results in knowledge gaps which are filled by the information, dispersed in wide range of literature, but rarely covered in a short and condensed form. To address this issue and with the aim of providing a concise and simple explanation of fuel cell operation, we propose a simple educational model of the most relevant processes in the fuel cell, aimed at proper description of causal relations. The derivation of model equations provides an intuitive understanding of electric potentials acting on protons on the microscopic level and relates this knowledge to the common terminology in fuel cell research community, such as catalyst electric overpotential and internal membrane resistance. The results of the model fit well with experimental data, indicating that a simple description, provided in the paper, is sufficient for intuitive understanding of fuel cell operation.
ARTICLE | doi:10.20944/preprints202310.1888.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: P-cadherin; c-Met; cell proliferation; cell migration; Head and neck cancer
Online: 30 October 2023 (10:05:42 CET)
(1) Background: P-cadherin (CDH3) is a transmembrane protein that plays a crucial role in maintaining the structural integrity of epithelial tissue and homeostasis. Its role in carcinogenesis remains a subject of debate, as its behavior can vary depending on the molecular context and the specific tumor cell model under study. In this study, we explored the role of P-cadherin in head and neck squamous cell carcinoma (HNSCC) and the mechanism underlying its function. (2) Methods: We analyzed P-cadherin expression in HNSCC patients using The Cancer Genome Atlas (TCGA) database. For in vitro functional analysis, we conducted proliferation, migration, invasion, and western blot assays after either suppressing or overexpressing P-cadherin. For in vivo functional analysis, we utilized mouse xenograft models. (3) Results: P-cadherin was significantly overex-pressed in tumor samples compared to normal samples in the TCGA-HNSCC cohort. P-cadherin knockdown resulted in decreased proliferation, migration, and invasion compared to control cells, while P-cadherin overexpression increased cell proliferation and migration in HNSCC cells. We discovered that c-Met functioned as an upstream regulator of P-cadherin. Surprisingly, we found that P-cadherin knockdown increased the phosphorylation of c-Met and STAT3. Combining P-cadherin siRNA with the c-Met inhibitor SU11274 resulted in a more effective reduction in HNSCC cell growth, both in vitro and in vivo, compared to either treatment alone. (4) Conclusions: Our study uncovered a previously unknown aspect of P-cadherin-mediated c-Met regulation. The enhanced activation of c-Met/STAT3 following P-cadherin inhibition could be responsible for the survival of resistant tumor cells. Therefore, dual inhibition of P-cadherin and c-Met may be a potentially effective approach for treating HNSCC.
ARTICLE | doi:10.20944/preprints202307.1674.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: cisplatin resistance; Z-Ligustilide; cell cycle arrest; cell apoptosis; phospholipid synthesis; PLPP1
Online: 25 July 2023 (09:44:55 CEST)
Z-ligustilide is a main active ingredient in the volatile oil of Angelica sinensis, a traditional Chinese medicine. Cisplatin is a commonly used chemotherapy drug for the treatment of lung cancer. Efficacy is often limited by the development of drug resistance after long-term treatment. Here, we investigated the effect of the combination of Z-ligustilide and cisplatin (Z-ligustilide+cisplatin) on resistance of cisplatin-resistant lung cancer cells and its action mechanism. Cell viability was analyzed by cell counting kit-8 (CCK-8) assay. Cell cycle and cell apoptosis were examined by flow cytometry assay. mRNA and protein levels of factors related to cell cycle and apoptosis were analyzed by real-time PCR and western blot. Liquid chromatography-mass spectrometry (LC-MS) analysis and RNA sequencing in A549, A549/DDP and A549/DDP cells treated with the Z-ligustilide+cisplatin were performed. The expression of PLPP1 was analyzed by the Cancer Genome Atlas (TCGA). The correlation between PLPP1 and prognosis was evaluated by immunohistochemistry and Kaplan-Meier (KM) plotter analysis. We found that Z-ligustilide+cisplatin could decrease the cell viability of cisplatin-resistant lung cancer cells. Z-ligustilide+cisplatin induced cell cycle arrest, and promoted cell apoptosis of cisplatin-resistant lung cancer cells. Metabolomics combined with transcriptomics revealed that Z-ligustilide+cisplatin inhibited phospholipid synthesis by upregulating the expression of PLPP1. Furthermore, PLPP1 expression was positively correlated with good prognosis. Knockdown of PLPP1 abolished the effects of Z-ligustilide+cisplatin on cell cycle and apoptosis. Z-ligustilide+cisplatin inhibited the activation of AKT by reducing the levels of PIP3 levels. Z-ligustilide+cisplatin induced cell cycle arrest and promoted cell apoptosis of cisplatin-resistant lung cancer cells by inhibiting PLPP1-mediated phospholipid synthesis.
ARTICLE | doi:10.20944/preprints202304.0879.v1
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: renal cell tumours; renal cell carcinomas; immunohistochemistry; immunofluorescence; mito-chondria; electron microscopy
Online: 25 April 2023 (03:58:57 CEST)
The precise differentiation of renal cell tumours (RCTs) is sometimes hard to achieve using standard imaging and histopathological methods. This study investigated 43 cell renal cell car-cinomas (ccRCC), 15 papillary renal cell carcinomas (pRCC), 20 chromophobe renal cell carcino-mas (chRCC), and 18 renal oncocytomas (RO), stained with anti-mitochondria antibody (Thermo Scientific) by immunohistochemistry and immunofluorescence, and assessed by electron micros-copy, in order to define mitochondria distribution pattern (coarse scanty, moderate granular and diffuse granular). Thus, the majority of males had coarse granular staining in the tumours, while females were almost equally distributed among groups (p=0.005). An average patient age, tumour side and dimension, and tumour stage were similar in all staining pattern groups. However, pathohistological tumour types had significantly different expression patterns, with the lower amount of staining detected in majority of ccRCC, moderate expression in all chRCC, and diffuse expression in all RO, pRCC and two cases of ccRCC (p<0.001) presented with higher nuclear grade (p=0.005). Moreover, with increased distribution of mitochondria, the intensity of staining was higher (p<0.001). Here we present a strategy that utilizes mitochondria detection to differentiate RO from chRCC, as well as to distinguish other frequent RCTs, such as ccRCC and pRCC.
REVIEW | doi:10.20944/preprints202204.0084.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: enteric progenitor cell; zebrafish; inflammation; Hirschsprung Disease; neural crest cell; ENS neuropathies
Online: 9 April 2022 (01:49:53 CEST)
The neural-crest derived enteric nervous system (ENS) is the intrinsic nervous system of the gastrointestinal (GI) tract and controls all gut functions, including motility. Lack of ENS neurons causes various ENS disorders such as Hirschsprung Disease. One treatment option for ENS dis-orders includes the activation of resident stem cells to regenerate ENS neurons. Regeneration in the ENS has mainly been studied in mammalian species using surgical or chemically-induced injury methods. These mammalian studies showed a variety of regenerative responses with generally limited regeneration of ENS neurons, but (partial) regrowth and functional recovery of nerve fibers. Several aspects might contribute to the variety in regenerative responses, including observation time after injury, species, and gut region targeted. Zebrafish have recently emerged as a promising model system to study ENS regeneration as larvae possess the ability to generate new neurons after ablation. As the next steps in ENS regeneration research, we need a detailed under-standing of how regeneration is regulated on a cellular and molecular level both in animal models with high and low regenerative capacity. Understanding the regulatory programs necessary for robust ENS regeneration will pave the way for using neural regeneration as a therapeutic approach to treating ENS disorders.
REVIEW | doi:10.20944/preprints202112.0262.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: tumor microenvironment; connexins; cell-cell contacts; tumor stroma; carcinogenesis; tumor development; metastasis
Online: 16 December 2021 (08:12:13 CET)
The modern paradigm of studying the processes of carcinogenesis and vital activity of tumor tissues implies increased attention to constituents of tumor microenvironment (TME) and their interactions. These interactions between the cells in TME can be mediated via protein junctions of different types. Connexins (Cnxs) are one of the major contributors to intercellular communication. They form gap junctions responsible for the transfer of ions, metabolites, peptides, miRNA, etc. between neighboring tumor cells as well as between tumor and stromal cells. Cnx hemichannels mediate purinergic signaling and bidirectional molecular transport with the extracellular environment. Additionally, Cnxs were reported to localize in tumor-derived exosomes and facilitate the release of their cargo. A large body of evidence implies that the role of connexins in cancer is multifaceted. Pro- or anti-tumorigenic properties of connexins are determined by their abundance, localization and functionality as well as channel assembly and non-channel functions. In this review we have summarized the data on the Cnxs contribution in TME and to the cancer initiation and progression.
ARTICLE | doi:10.20944/preprints202005.0445.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: oral cancer; cancer-associated fibroblasts; metastasis; cell migration; cell invasion; Akt; EGFR
Online: 27 May 2020 (08:25:20 CEST)
Oral cancer cells (TYS) and the signalling pathways involved in metastasis, in response to cancer-associated fibroblasts (CAFs, COM) and normal oral mucosal fibroblasts (MM1) was studied. Metastatic cell behaviour was observed by cell-scatter, 3D-collagen gel migration and 3D-spheroid invasion assays. Akt, MAPK, EGFR, TGFβRii and CXCR4 inhibitors were used to identify the signalling pathways involved. Signalling pathway protein expression and activation were assessed by SDS-PAGE and Western Blotting. COM-CM (conditioned medium) and MM1-CM stimulated cancer cell scattering, which was blocked only by the Akt inhibitor. COM-CM induced scattered cancer cells showed higher levels of Akt phosphorylation than the negative control and MM1-CM. Migration and invasion of TYS cells into the collagen gels from the spheroids was stimulated by CM from both sources, compared to the negative control. COM cells stimulated TYS, cancer cell invasion into the collagen more than MM1 and the control. Akt and EGFR inhibitors effectively blocked CM and COM cell-induced invasion. Akt-silenced cancer cells were not stimulated to migrate and invade by fibroblast-CM and did not survive addition of the EGFR inhibitor. This suggests that CAFs stimulate oral cancer cell migration and invasion in an Akt- dependent manner. EGFR and Akt are potential therapy targets in metastatic oral cancer.
BRIEF REPORT | doi:10.20944/preprints202003.0198.v1
Subject: Biology And Life Sciences, Virology Keywords: human cytomegalovirus; progenitor cell; hematopoietic stem cell transplant; myelosuppression; hematopoiesis; humanized mice
Online: 12 March 2020 (04:26:12 CET)
Human Cytomegalovirus (HCMV) infection is a serious complication in hematopoietic stem cell transplant (HSCT) recipients due to virus-induced myelosuppression and impairment of stem cell engraftment. Despite the clear clinical link between myelosuppression and HCMV infection, little is known about the mechanism(s) by which the virus inhibits normal hematopoiesis because of the strict species specificity and the lack of surrogate animal models. In this study, we developed a novel humanized mouse model system that recapitulates the HCMV-mediated engraftment failure after hematopoietic cell transplantation. We observed significant alterations in the hematopoietic populations in peripheral lymphoid tissues following engraftment of a subset of HCMV+ CD34+ HPCs within the transplant suggesting that a small proportion of HCMV-infected CD34+ HPCs can profoundly affect HPC differentiation in the bone marrow microenvironment. This model will be instrumental to gain insight into the fundamental mechanisms of HCMV myelosuppression after HSCT and provides a platform to assess novel treatment strategies.
ARTICLE | doi:10.20944/preprints201701.0088.v2
Subject: Biology And Life Sciences, Endocrinology And Metabolism Keywords: Adipose derived stem cell (ASC); Regenerative medicine; embryonic stem cell marker network
Online: 20 January 2017 (04:56:06 CET)
The stromal vascular cell fraction (SVF) of visceral and subcutaneous adipose tissue (VAT and SAT) has increasingly come into focus in stem cell research, since these compartments represent a rich source of multipotent adipose-derived stem cells (ASCs). ASCs exhibit a self- renewal potential and differentiation capacity. Our aim was to study the different expression of embryonic stem cell markers NANOG, SOX2 and OCT3/4 and to evaluate if there exists a hierarchal role in this network in ASCs derived from both SAT and VAT. ASCs were isolated from SAT and VAT biopsies of 72 consenting patients (23 men, 47 women; age 45 ± 10; BMI between 25 and 30 range) undergoing elective open-abdominal surgery. Sphere-forming capability was evaluated by plating cells in low adhesion plastic. Stem cell markers CD90 and CD105 were analyzed by flow cytometry and stem cell transcription factors NANOG, SOX2 and OCT3/4 were detected by immunoblotting and Real-Time PCR. NANOG, SOX2 and OCT3/4 interplay was explored by gene silencing. ASCs from VAT and SAT confirmed their mesenchymal stem cell (MSC) phenotype expressing the specific MSC markers CD90, CD105, NANOG, SOX2 and OCT3/4. NANOG silencing induced a significant OCT 3/4 (70% ± 0.05) and SOX2 (75% ± 0.03) down-regulation whereas SOX2 silencing did not affect NANOG gene expression. Adipose tissue is an important source of MSC, and siRNA experiments endorse a hierarchical role of NANOG in the complex transcription network that regulates pluripotency and plasticity.
REVIEW | doi:10.20944/preprints202112.0525.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: colorectal cancer; immunotherapy; checkpoint blockade; adoptive cell therapy; monoclonal antibodies; oncolytic viruses; anti-cancer vaccines; cytokine; T cell; NK cell
Online: 31 December 2021 (15:14:39 CET)
Though early-stage colorectal cancer has a high 5-year survival rate of 65-92% depending on the specific stage, this probability drops to 13% after the cancer metastasizes. Frontline treatments for colorectal cancer such as chemotherapy and radiation often produce dose-limiting toxicities in patients and acquired resistance in cancer cells. Additional targeted treatments are needed to improve patient outcomes and quality of life. Immunotherapy involves treatment with peptides, cells, antibodies, viruses, or small molecules to engage or train the immune system to kill cancer cells. Preclinical and clinical investigations of immunotherapy for treatment of colorectal cancer including immune checkpoint blockade, adoptive cell therapy, monoclonal antibodies, oncolytic viruses, anti-cancer vaccines, and immune system modulators have been promising, but demonstrate limitations for patients with proficient mismatch repair enzymes. In this review, we discuss preclinical and clinical studies investigating immunotherapy for treatment of colorectal cancer and predictive biomarkers for response to these treatments. We also consider open questions including optimal combination treatments to maximize efficacy, minimize toxicity, and prevent acquired resistance and approaches to sensitize mismatch repair proficient patients to immunotherapy.
ARTICLE | doi:10.20944/preprints202109.0139.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: Adipose-derived Stem Cell; Flow-Cytometry; Mesenchymal Stem Cell; Stromal Vascular Fraction; Immunophenotyping; Immunohistochemistry; Fluorescent Antibody Technique; Cell Separation Method
Online: 8 September 2021 (10:50:49 CEST)
Background: Developing an efficient and standardized method to isolate and characterize adipose-derived stem cells (ASCs) from the stromal vascular fraction (SVF) of the adipose tissue for clinical application represents one of the major challenges in cell therapy and tissue engineering. Methods: In this study, we proposed an innovative, non-enzymatic protocol to collect clinically useful ASCs within freshly isolated SVF from adipose tissue by centrifugation of the infranatant portion of lipoaspirate and to determine the characteristic cytofluorimetric pattern, prior to in vitro culture. Results: The SVF yielded a mean of 73,32 \pm\ 10,89% cell viability evaluated with CALCEINA-FITC, i.e. cell-permeant dye. The ASCs were positive for PC7-labeled mAb anti-CD34 and negative for both PE-labeled mAb anti-CD31 and APC-labeled mAb anti-CD45. The frequency of ASCs estimated according to the panel of cell surface markers used was 51,06%\ \pm 5,26% versus the unstained ASCs subpopulation that was 0,74%\pm0,84% (P<0.0001). The ASCs events/\muL were 1602,13/\muL \pm 731,87/\muL. Conclusion: Our findings suggested that ASCs found in freshly isolated adipose SVF obtained by centrifugation of lipoaspirate can be immunophenotypically identified with a basic panel of cell surface markers. These findings aimed to provide standardization and contribute to reducing the inconsistency on reported cell surface antigens of ASC derived from the existing literature.
ARTICLE | doi:10.20944/preprints202211.0080.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Tumor initiation; Germ cell traits of tumors; Primordial germ cell-like tumor cells; Somatic to Pri-mordial germ cell-like transformation; Embryonic/germ cell hypothesis of tumor; Breast cancer
Online: 4 November 2022 (01:04:58 CET)
It has been proposed that tumourigenicity was an intrinsic feature of embryonic/germ cell developmental axis as well as embryonic/germ cell-related genes play a crucial role in tumourigenicity. Our previous studies indicated that primordial germ cell (PGC)-like potential could be reactivated in tumourigenesis. In this study, 4T1, 168FARN and 67NR cells which originated from the same mouse breast cancer were studied and the results indicated that the acquisition of embryonic/germ cell-like state is essential for tumourigenicity. We further demonstrated that somatic to PGC-like transformation (SPLT) was activated in 4T1 cells and that inhibition of PGC-like cell formation by depleting pluripotency and/or PGC specification-related genes markedly repressed SPLT and the tumourigenicity. Collectively, our findings reveal that tumourigenicity is linked to the acquisition of PGC-like state through SPLT in 4T1 cells, provide new insight into deeper understanding the biological nature of tumours and novel therapeutical strategies for cancer targeting.
REVIEW | doi:10.20944/preprints202310.0415.v1
Subject: Engineering, Automotive Engineering Keywords: fuel-cell vehicles; refueling hydrogen stations; fuel cell technologies; artificial intelligence; quantum computing
Online: 9 October 2023 (09:27:49 CEST)
The increasing global demand for energy and the pressing challenge of environmental pollution necessitates a paradigm shift towards sustainable energy sources. Hydrogen, a viable renewable energy carrier, has the potential to substantially alleviate these concerns. This review offers a comprehensive exploration of the technologies imperative to the production and operation of fuel cell vehicles (FCVs), ranging from various fuel cell types, hydrogen storage methods, fueling station logistics, batteries in hydrogen vehicles, and the emerging influence of artificial intelligence and quantum computing. An analytical overview of global adoption patterns reveals significant geographical disparities, with the United States and South Korea at the forefront of FCV integration, primarily in the form of passenger cars, followed by buses and trucks. Asia emerges as the region with the highest proportion of FCVs. This paper also delves into the diverse challenges facing FCV implementation, shedding light on the essential role of continued investment in the evolution of sustainable transportation systems. Furthermore, it provides insights into the varying contributions of different companies in the field, demonstrating the collective effort required to advance this promising technology. The comprehensive exploration provided in this review aids in understanding the opportunities, challenges, and potential of hydrogen as an integral player in the future of sustainable transportation. The increasing need for energy carriers and the rise of environmental pollution have driven the exploration of renewable energy sources, with hydrogen being a promising option.
ARTICLE | doi:10.20944/preprints202309.0973.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: β-cell loss; β-cell dedifferentiation; diabetes; GSIS; THC; CBD; THCV; CBC; CBN
Online: 15 September 2023 (04:54:38 CEST)
Our findings indicate that all five phytocannabinoids reduce HG-HL-induced -cell loss likely through reducing apoptosis and pyroptosis. The protective effects of CBD, THCV, CBC, and CBN were seen in the GSIS impairment by HG-HL. Although all five phytocannabinoids tested in this research demonstrated the capability to inhibit β-cell dedifferentiation induced by HG-HL, CBD seems to be more effective compared to the other phytocannabinoids, as indicated by the specific biomarker responses of β-cells and progenitor cells to CBD.
ARTICLE | doi:10.20944/preprints202307.0303.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: stress response; poplar; lignin; bioethanol; cell wall; cell death; biofuels; stress response proteins
Online: 6 July 2023 (03:28:59 CEST)
Production of biofuel from lignocellulosic biomass is relatively low due to the limited knowledge about natural cell wall loosening and cellulolytic processes in plants. Industrial separation of cellulose fiber mass from lignin, its saccharification and alcoholic fermentation is still cost-ineffective and environmental unfriendly. Assuming that the green transformation is inevitable and that the new sources of raw materials for biofuels are needed, we decided to study cell death - a natural process occurring in plants in a context of reducing the recalcitrance of lignocellulose for production of second generation bioethanol. “members of the enzyme families responsible for lysigenous aerenchyma formation were identified during the root hypoxia stress in Arabidopsis thaliana cell death mutants. The cell death regulatory genes, LESION SIMULATING DISEASE 1 (LSD1), PHYTOALEXIN DEFICIENT 4 (PAD4) and ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1) conditionally regulate the cell wall when suppressed in transgenic aspen. During four years of growth in the field the following effects were observed: lignin content was reduced, the cellulose fiber polymerization degree increased and the growth itself was unaffected. The wood of transgenic trees was more efficient as a substrate for saccharification, alcoholic fermentation and bioethanol production. The presented results may trigger the development of novel biotechnologies in the biofuel industry.
ARTICLE | doi:10.20944/preprints202306.1624.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: cell penetrating peptide; bioportide; eyes absent protein; neoblast; planarian; confocal microscopy; stem cell
Online: 22 June 2023 (12:29:16 CEST)
Djeya1 (RKLAFRYRRIKELYNSYR), is a very effective cell penetrating peptide (CPP) which mimics the α5 helix of the highly conserved Eya domain (ED) of eyes absent (Eya) proteins. The objective of this study was to bioengineer analogues of Djeya1 that, following effective translocation into planarian tissues, would reduce the ability of neoblasts (totipotent stem cells) and their progeny to regenerate the anterior pole in decapitated S. mediterranea. As a strategy to increase the propensity for helix formation, molecular bioengineering of Djeya1 was achieved by the mono-substitution of the helicogenic aminoisobutyric acid (Aib) at three species variable sites: 10,13,16. CD analyses indicted that Djeya1 is highly helical and that Aib-substitution had little influence on secondary structure. Aib-substituted Djeya1 analogues are highly efficient CPPs, devoid of influence upon cell viability or proliferation. All three peptides increase the migration of PC-3 cells which express high concentrations of Eya. Two peptides, [Aib13]Djeya1 and [Aib16]Djeya1, are bioportides which delay planarian head regeneration. As neoblast are the only cell population capable of division in planaria, these data indicate that bioportide technologies could be utilised to directly manipulate other stem cells in situ, thus negating any requirement for genetic manipulation.
ARTICLE | doi:10.20944/preprints202305.0849.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Escherichia coli; bacterial transformation; plasmid-to-cell ratio; competent cell concentration; incubation time
Online: 11 May 2023 (11:49:13 CEST)
Bacterial transformation is the essential tool for introducing foreign DNA into bacterial cells in a host of recombinant technology applications useful for biomanufacturing and drug production. Thus far, chemically competent cells remain an important enabling technology for bacterial transformation given its facile transformation approach. However, many parameters affect transformation efficiency, and there is relatively little documentation of their cross-interacting effect in the literature. This work explores the roles played by incubation time on ice, competent cell concentration, and plasmid-to-cell ratio on transformation efficiency in Escherichia coli DH5α. Results revealed that increases in incubation time improve transformation efficiency, but 2 minutes incubation still yield appreciable efficiency. On the other hand, low concentration competent cells (106 CFU/mL) yielded significant improvement in transformation efficiency compared to high concentration competent cells (108 CFU/mL). In terms of plasmid-to-cell ratio, higher ratio increases transformation efficiency. Overall, bacterial transformation is incompletely understood particularly in the area of cross-interacting parameters. Experiments reported here revealed the possibility of short duration transformation where lower competent cell concentration and higher plasmid-to-cell ratio could improve transformation.
ARTICLE | doi:10.20944/preprints202305.0296.v1
Subject: Engineering, Energy And Fuel Technology Keywords: Metal-air batteries cell; electrode materials; open cell foam; replication process; effective conductivity
Online: 5 May 2023 (04:24:22 CEST)
The global context of research for new sustainable energy storage technologies makes it a very active sector with significant scientific and economic challenges. Indeed, due to the irregular development of renewable energies and the shutdown of traditional power facilities, it is difficult to maintain a stable balance in terms of supply and demand: energy storage can help in particular for substantial changes in the latter. Metal air batteries have a higher energy density and are safer than other available energy storage devices. Based on the existing and proven lead-acid battery technology, this paper proposed an open cell foam manufactured by the Excess Salt Replication process for use as an anode for lead-air battery cellsies with sulphuric acid as the electrolyte. This will save lead and reduce the battery weight. A 25% antimonial lead alloy was used to produce open cell foams with a cell diameter between 2 mm and 5 mm for the antimonial lead-air battery. Preliminary results of the effective electrical conductivity of self-discharged primary battery cells, measured experimentally, showed that all antimonial lead foam-air battery cellsies performed better than that made from the same dense non porous antimonial lead alloy. This is generally due to their important specific surface area where oxidation-reduction reactions took place. A correlation between the effective electrical conductivity and the cell diameter has been established and the highest conductivity was obtained with a cell diameter of 5mm. The feasibility of such an electrical system has been demonstrated.
ARTICLE | doi:10.20944/preprints202301.0569.v1
Subject: Medicine And Pharmacology, Endocrinology And Metabolism Keywords: diabetes; type 1 diabetes; regeneration; axolotl; salamander; beta cell; beta cell regeneration; streptozotocin
Online: 31 January 2023 (04:11:24 CET)
Diabetes is a group of diseases characterized by loss of β cell mass and/or -function, resulting in hyperglycemia. Approx. 537 million people worldwide suffer from diabetes – a number which is expected to increase. Diabetes is primarily treated by exogenous insulin, which comes with the challenges of maintaining glycemic control to prevent ketoacidosis and severe complications. The need for a curative treatment has initiated the research in β cell regeneration. Several studies in mice have identified essential genes for β cell fate, which can be manipulated in other cells to induce generation of new β cells. Zebrafish, a regeneration-positive animal model, has shown several different sources of new β cells, including regeneration by self-replication, neogenesis by duct-associated progenitor cells, and transdifferentiation of other endocrine islet cells. The animal models used in this research area are either limited by their low regenerative ability (mice), or their small size and remoteness from humans (zebrafish). There is a need for new animal models of diabetes, in which the molecular pathways of endogenous regeneration can be studied. This study proposes the axolotl salamander (Ambystoma mexicanum) as a model for studying the regeneration of β cells. The axolotl has shown great regenerative capability, as they have proven capable of regenerating amputated limbs, and hearts with myocardial infarction, among other organs. This study aims to establish a diabetic axolotl model, investigate their regenerative ability in the pancreas, and examine the potential systemic effects of the induced disease. In a pilot study, five different protocols using STZ (streptozotocin) were tested, and the most optimal protocol was found. Furthermore, the glucose tolerance test was optimized to characterize the glycemic state of the animals. The effect of the treatment on blood glucose levels was measured to characterize the development and decline of the disease. The histological changes in the pancreas were examined. Moreover, the systemic effects of the STZ treatment were investigated in blood and urine. The study indicated that it is possible to induce diabetes in the axolotl, but variations between the animals should be minimized, or the sample size should be increased to conduct a satisfying experiment, as it was not possible to induce diabetes in all animals. Regeneration was not observed histologically, but a restoration of blood glucose levels was seen over the span of the experiment. Lastly, edema formation was observed in some of the STZ-treated animals, but the cause of edema remains undetermined.
REVIEW | doi:10.20944/preprints202210.0342.v1
Subject: Biology And Life Sciences, Virology Keywords: long COVID; PASC; long haulers; NETosis; T cell; NK cell; DC; neutrophil; macrophage
Online: 24 October 2022 (02:12:06 CEST)
A significant number of persons with coronavirus disease 2019 (COVID-19) experience persistent, recurrent, or new symptoms several months after the acute stage of severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) infection. This phenomenon, termed Post-Acute Sequelae of SARS-CoV-2 (PASC) or Long COVID, is associated with high viral titers during acute infection, a persistently hyperactivated immune system, tissue injury by NETosis-induced micro-thrombofibrosis (NETinjury), microbial translocation, complement deposition, fibrotic macrophages, the presence of auto-antibodies, and lymphopenic immune environments. Here, we review the current literature on the immunological imbalances that occur during PASC. Specifically, we focus on data supporting common immunopathogenesis and tissue injury mechanisms shared across this highly heterogenous disorder including NETosis, coagulopathy, and fibrosis. Mechanisms include changes in leukocyte subsets/functions, fibroblast activation, cytokine imbalances, lower cortisol, autoantibodies, co-pathogen reactivation, and residual immune activation driven by persistent viral antigens and/or microbial translocation. Taken together, we develop the premise that SARS-CoV-2 infection results in PASC as a consequence of acute and/or persistent single or multiple organ injury mediated by PASC determinants to include degree of host response (inflammation, NETinjury), residual viral antigen (persistent antigen) and exogenous factors (microbial translocation). Determinants of PASC may be amplified by co-morbidities, age, and sex. Keywords: long COVID, PASC, long haulers, NETosis, T cell, NK cell, DC, neutrophil,
REVIEW | doi:10.20944/preprints202209.0076.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: innate lymphoid cells; cell therapy; cancer; immunotherapy; antitumor immune response; adoptive cell therapy
Online: 6 September 2022 (03:17:36 CEST)
Although the first cancer immunotherapy was given in the clinic more than a century ago, this line of treatment has remained more of a distant goal than a practical therapy due to limited understanding of the tumor microenvironment and the mechanisms at play within it, which lead to failures of numerous clinical trials. However, in the last two decades, the immune checkpoint inhibitors and chimeric antigen receptor-T cell therapies have revolutionized the treatment of cancer and provided proof-of-concept that immunotherapies are a viable option. So far, immunotherapies have majoritarily focused on utilizing T cells, however T cells are not autonomous but rather function as part of, and therefore are influenced by, a vast cast of other immune cells, including innate lymphoid cells (ILCs). Here, we summarize the role of ILCs, especially helper ILCs, in tumor development, progression and metastasis, as well as their potential to be used as immunotherapy for cancer. By reviewing the studies that used helper ILCs as adoptive cell therapy, we highlight the rationale behind considering these cells as novel adoptive cell therapy for cancer as well as identify open questions and areas for future research.
ARTICLE | doi:10.20944/preprints202206.0213.v1
Subject: Computer Science And Mathematics, Computational Mathematics Keywords: cell migration; optimal control; geometric partial differential equations; mechanical membrane forces; cell polarisation
Online: 15 June 2022 (05:54:15 CEST)
Cell migration is essential for physiological, pathological and biomedical processes such as, in embryogenesis, wound healing, immune response, cancer metastasis, tumour invasion and inflammation. In light of this, quantifying mechanical properties during the process of cell migration is of great interest in experimental sciences, yet few theoretical approaches in this direction have been studied. In this work, we propose a theoretical and computational approach based on the optimal control of geometric partial differential equations to estimate cell membrane forces associated with cell polarisation during migration. Specifically, cell membrane forces are inferred or estimated by fitting a mathematical model to a sequence of images, allowing us to capture dynamics of the cell migration. Our approach offers a robust and potentially accurate framework to compute geometric mechanical membrane forces associated with cell polarisation during migration and also yields geometric information of independent interest, we illustrate one such example that involves quantifying cell proliferation levels which are associated with cell division, cell fusion or cell death.
ARTICLE | doi:10.20944/preprints202203.0154.v1
Subject: Medicine And Pharmacology, Gastroenterology And Hepatology Keywords: Colorectal cancer; Cancer stem cell; Neural progenitor cell; Wnt/β-catenin; K-Ras
Online: 10 March 2022 (14:26:20 CET)
Cancer stem cells (CSCs) are a tumor cell subpopulation that drives tumor progression and metastasis, leading to poor overall survival of patients. In colorectal cancer (CRC), hyper-activation of Wnt/β-catenin signaling by mutation of both Adenomatous polyposis coli (APC) and K-Ras increases the size of the CSC population. We previously showed that the CPD0857 inactivates Wnt/β-catenin signaling by promoting ubiquitin-dependent proteasomal degradation of β-catenin and Ras proteins, thereby decreasing proliferation and increasing apoptosis of CRC lines. CPD0857 also decreased growth and invasiveness of CRC cells harboring mutant K-Ras resistant to EGFR mAb therapy. Here, we show that CPD0857 treatment decreases proliferation and increases neuronal differentiation of neural progenitor cells (NPCs). CDP0857 effectively reduced expression of CSC markers and suppressed self-renewal capacity. CPD0857 treatment also inhibited proliferation and expression of CSC markers in D-K-Ras MT cells carrying K-Ras, APC and PI3K mutations, indicating inhibition of PI3K/AKT signaling. Moreover, CPD0857-treated xenograft mice showed regression of tumor growth and decreased numbers of CSCs in tumors. We conclude that CPD0857 could serve as the basis of a drug development strategy targeting CSCs activated through Wnt/β-catenin-Ras MAPK-PI3K/AKT signaling in CRCs.
ARTICLE | doi:10.20944/preprints202110.0039.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: zebrafish; lateral line; neuromast; hair cell; ototoxicity; toxicity; regeneration; cell death; neomycin; aminoglycosides
Online: 4 October 2021 (10:27:34 CEST)
Acute chemical ablation of lateral line hair cells is an important tool to understand lateral line-mediated behaviors in free-swimming fish larvae and adults. However, lateral line-mediated behaviors have not been described in fish larvae prior to swim bladder inflation, possibly because single doses of ototoxin do not effectively silence lateral line function at early developmental stages. To determine if ototoxins can effectively silence the lateral line during early development, we repeatedly expose zebrafish larvae to the ototoxin neomycin during a 36-hour period from 3-4 days post-fertilization (dpf). We use simultaneous transgenic and vital dye labeling of hair cells to compare 6- hour and 12-hour repeated treatment timelines and neomycin concentrations between 0–400 µM in terms of larval survival, hair cell death, regeneration, and functional recovery. Following exposure to neomycin, we find that the emergence of newly functional hair cells outpaces cellular regeneration, likely due to the maturation of ototoxin-resistant hair cells that survive treatment. Furthermore, hair cells of 4 dpf larvae exhibit faster recovery compared to 3 dpf larvae. Our data suggest that the rapid functional maturation of ototoxin-resistant hair cells limits the effectiveness of chemical-based methods to disrupt lateral line function. Furthermore, we show that repeated neomycin treatments can continually ablate lateral line hair cells between 3–4 dpf in larval zebrafish.
ARTICLE | doi:10.20944/preprints202011.0232.v2
Subject: Chemistry And Materials Science, Electrochemistry Keywords: Lithium-ion-cell; Electrode dilation; Mechanical strain; Cell-format; Layer resolved mechanical simulation
Online: 12 May 2021 (14:06:24 CEST)
Electrochemical-mechanical interactions, in particular pressure-induced ones, have been identified to be a cause for lithium-plating in lithium-ion cells. Mechanically-induced porosity inhomogeneities in the separator layers due to electrode expansion during charging especially lead to cell internal balancing currents and can cause localized plating. To identify cell-format and cell-material dependent mechanical weak spots, a layer-resolved mechanical simulation of different cell types and cell-material combinations is presented in this work. The simulation results show distinctive layer strain patterns for different cell-types that coincide with localized lithium-plating found in post-mortem cells. Additionally, the effects of cell bracing in battery modules is investigated and a method to mitigate the increased layer strain due to bracing counterforces is proposed that also increases cell energy density for hardcase-type automotive cells.
REVIEW | doi:10.20944/preprints202006.0277.v2
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: Diabetes; transcription factor; β-cell mass; pluripotent stem cells; pancreatic progenitors; cell therapy
Online: 19 October 2020 (16:04:27 CEST)
Understanding the biology underlying the mechanisms and pathways regulating pancreatic β-cell development is necessary to understand the pathology of diabetes mellitus (DM), which is characterized by the progressive reduction in insulin producing β-cell mass. Pluripotent stem cells (PSCs) can potentially offer an unlimited supply of functional β-cells for cellular therapy and disease modeling of DM. Homeobox protein NKX6.1 is a transcription factor (TF) that plays a critical role in pancreatic β-cell function and proliferation. In human pancreatic islet, NKX6.1 expression is exclusive toβ-cells and is undetectable in other islet cells. Several reports showed that activation of NKX6.1 in PSC-derived pancreatic progenitors (MPCs), expressing PDX1 (PDX1+/NKX6.1+), warrants their future commitment to monohormonal β-cells. However, further differentiation of MPCs lacking NKX6.1 expression (PDX1+/NKX6.1-) results in an undesirable generation of non-functional polyhormonal β-cells. The importance of NKX6.1 as a crucial regulator in MPC specification into functional β-cells directs attentions to further investigating its mechanism and enhancing NKX6.1 expression as a mean to increase β-cell function and mass. Here, we shed light on the role of NKX6.1 during pancreatic β-cell development and in directing the MPCs to functional monohormonal lineage. Furthermore, we address the transcriptional mechanisms and targets of NKX6.1 as well as its association with diabetes.
ARTICLE | doi:10.20944/preprints202007.0627.v1
Subject: Medicine And Pharmacology, Pediatrics, Perinatology And Child Health Keywords: Erythrocytapheresis; red blood cell exchange; sickle cell disease; target HbS level; heparin locking
Online: 26 July 2020 (02:22:35 CEST)
The aim of our study was to describe our experience using a Spectra Optia® automated apheresis system in children with sickle cell disease (SCD). We used automated red blood cell exchange (RCE) to treat acute and chronic complications in 75 children with SCD who had a median age of 10 years [7-13]. We analysed 649 exchange sessions. Peripheral venous access was limited in a number of the children, thus requiring a femoral central double‐lumen venous catheter (CVC). We recommend the use of heparin locking, with 500 units in each lumen of a CVC. This method was well tolerated, with few complications during the procedures. For preoperative prevention, all of the patients had achieved a post-RCE HbS level of <30% since this is a mandatory condition imposed by the anaesthesiologist. With a post-RCE Hb level of approximately 10-11 g/dL, a blood exchange volume of ≥32 mL/kg, and an interval between each RCE procedure of ≤30 days, it was able to maintain the residual HbS level below 30%. Despite a target pre‐exchange HbS level of 47%, we did not encounter a single stroke recurrence. Erythrocytapheresis is useful and safe for children with SCD.