ARTICLE | doi:10.20944/preprints201902.0172.v4
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: RNA-dependent amplification of mammalian mRNA; physiologically occurring intracellular PCR, iPCR; RNA-dependent RNA polymerase, RdRp; chimeric RNA; sense-strand RNA; antisense-strand RNA
Online: 12 June 2019 (12:21:59 CEST)
The transfer of protein-encoding genetic information from DNA to RNA to protein, a process formalized as the “Central Dogma of Molecular Biology”, has undergone a significant evolution since its inception. It was amended to account for the information flow from RNA to DNA, the reverse transcription, and for the information transfer from RNA to RNA, the RNA-dependent RNA synthesis. These processes, both potentially leading to protein production, were initially described only in viral systems, and although RNA-dependent RNA polymerase activity was shown to be present, and RNA-dependent RNA synthesisfound to occur, in mammalian cells, its function was presumed to be restricted to regulatory. However, recent results, obtained with multiple mRNA species in several mammalian systems, strongly indicate the occurrence of protein-encoding RNA to RNA information transfer in mammalian cells. It can result in the rapid production of the extraordinary quantities of specific proteins as was seen in cases of terminal cellular differentiation and during cellular deposition of extracellular matrix molecules. A malfunction of this process may be involved in pathologies associated either with the deficiency of a protein normally produced by this mechanism or with the abnormal abundanceof a protein or of its C-terminal fragment. It seems to be responsible for some types of familial thalassemia and may underlie the overproduction of beta amyloid in sporadic Alzheimer’s disease. The aim of the present article is to systematize the current knowledge and understanding of this pathway. The outlined framework introduces unexpected features of the mRNA amplification such as its ability to generate polypeptides non-contiguously encoded in the genome, its second Tier, a physiologically occurring intracellular polymerase chain reaction, iPCR, a Two-Tier Paradox and RNA Dark Matter. RNA-dependent mRNA amplification represents a new mode of genomic protein-encoding information transfer in mammalian cells. Its potential physiological impact is substantial, it appears relevant to multiple pathologies and its understanding opens new venues of therapeutic interference, it suggests powerful novel bioengineering approaches and its further rigorous investigations are highly warranted.
REVIEW | doi:10.20944/preprints202311.2011.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: allogeneic; chimeric antigen receptor; off-the-shelf; gene editing
Online: 1 December 2023 (03:05:54 CET)
This last decade, chimeric antigen receptor (CAR) T-cell therapy has become a real treatment option for patients with B-cell malignancies, while multiple efforts are being made to extend this therapy to other malignancies and broader patient populations. However, several limitations remain, including those associated with the time-consuming and highly personalized manufacturing of autologous CAR-Ts. Technologies to establish “off-the-shelf” allogeneic CAR-Ts with low alloreactivity are currently being developed, with a strong focus on gene editing technologies. Although these technologies have many advantages, they have also strong limitations including double-strand breaks in the DNA with associated multiple safety risks as well as the lack of modulation. As an alternative, non-gene editing technologies provide an interesting approach to support the development of allogeneic CAR-Ts in the future, with possibilities of fine-tuning gene expression and easy development. Here we will review the different ways allogeneic CAR-Ts can be manufactured and discuss which technologies are currently used. The biggest hurdles for successful therapy of allogeneic CAR-Ts will be summarized and finally an overview of the current clinical evidence for allogeneic CAR-Ts in comparison to its autologous counterpart will be given.
ARTICLE | doi:10.20944/preprints202301.0537.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: L-asparaginase; chimeric; in silico; immunogenicity; acute lymphoblastic leukemia
Online: 30 January 2023 (03:21:51 CET)
Acute lymphoblastic leukemia (ALL) is the most common cancer among children worldwide, characterized by an overproduction of undifferentiated lymphoblasts in the bone marrow. The treatment of choice for this disease is the enzyme L-asparaginase (ASNase) from bacterial sources. ASNase hydrolyzes circulating L-asparagine in plasma, leading to starvation of leukemic cells. The ASNase formulations of E. coli and E. chrysanthemi present notorious adverse effects, especially the immunogenicity they generate, which undermines both their effectiveness as drugs and patient safety. In this study, we developed a humanized chimeric enzyme from E. coli L-asparaginase, which would reduce the immunological problems associated with current L-asparaginase therapy. For these, the immunogenic epitopes of E. coli L-asparaginase (PDB: 3ECA) were determined and replaced with those of the less immunogenic Homo sapiens asparaginase (PDB:4O0H). The structures were modeled using the Pymol software and the chimeric enzyme was modeled using the SWISS MODEL service. A humanized chimeric enzyme with four subunits similar to the template structure was obtained, and the presence of asparaginase enzymatic activity was predicted by protein-ligand docking.
ARTICLE | doi:10.20944/preprints202212.0223.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Leishmaniasis; recombinant chimeric protein; serodiagnosis; visceral leishmaniasis; humans; dogs
Online: 13 December 2022 (02:38:38 CET)
Background: Visceral leishmaniasis (VL) is s critical public health problem in over ninety countries. The control measures adopted in Brazil have been insufficient when it comes to preventing the spread of this neglected disease. In this context, a precise diagnosis of VL in dogs and humans could help to reduce the number of cases of this disease. Distinct studies for the diagnosis of VL have used single recombinant proteins in serological assays; however, results have been variable, mainly in the sensitivity of the antigens. The development of multiepitope-based proteins could be relevant in solving such a problem. Methods: A chimeric protein (rMELEISH) was constructed based on amino acid sequences from kinesin 39 (k39), alpha-tubulin, and heat shock proteins HSP70 and HSP 83.1, and tested in ELISA for the detection of L. infantum infection in humans and dogs. Results: rMELEISH was able to discriminate between VL cases and cross-reactive diseases and healthy samples, with sensitivity and specificity values of 100% as compared to the use of a soluble Leishmania antigenic extract (SLA). Conclusions: Preliminary data suggest that the rMELEISH protein presents a potential to be tested in future studies against a larger serological panel for the diagnosis of canine and human VL.
REVIEW | doi:10.20944/preprints202309.1180.v1
Subject: Medicine And Pharmacology, Hematology Keywords: myeloma; daratumumab; bispecific antibodies; chimeric antigen receptor T-cells; immunotherapy
Online: 19 September 2023 (05:28:58 CEST)
The landscape of therapeutic measures to treat multiple myeloma has undergone a seismic shift since the dawn of the current century. This has been driven largely by the introduction of new classes of small molecules, such as proteasome blockers (e.g., bortezomib) and immunomodulators (e.g., lenalidomide), as well as by immunotherapeutic agents starting with the anti-CD38 monoclonal antibody daratumumab in 2015. Recently, other immunotherapies have been added to the armamentarium of drugs available to fight this malignancy. These include the bispecifics teclistamab, talquetamab, and elranatamab, and the chimeric antigen receptor (CAR) T-cell products idecabtagene vicleucel (ide-cel) and ciltacabtagene autoleucel (cilta-cel). While the accumulated benefits of these newer agents have resulted in a more than doubling of the disease’s five-year survival rate to nearly 60% and improved quality of life, the disease remains incurable, as patients become refractory to the drugs and experience relapse. This review covers the current scope of anti-myeloma immunotherapeutic agents, both those in clinical use and in development. Included in the discussion are additional monoclonal antibodies (mAbs), antibody-drug conjugates (ADCs), bi- and multi-targeted mAbs, and CAR T-cells and emerging natural killer (NK) cells, including products intended for “off-the-shelf” (allogeneic) applications. Emphasis is placed on the benefits of each along with the challenges that need to be surmounted if MM is to be cured.
ARTICLE | doi:10.20944/preprints202308.1611.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Cancer; Multiple Myeloma; Natural Killer; Immunotherapy; Chimeric Antigen Receptor; Allogenic
Online: 23 August 2023 (08:48:43 CEST)
Multiple myeloma (MM) has witnessed improved patient outcomes through advancements in therapeutic approaches. Notably, allogeneic stem cell transplantation, proteasome inhibitors, immunomodulatory drugs, and monoclonal antibodies have contributed to enhanced quality of life. Recently, a promising avenue has emerged with chimeric antigen receptor (CAR) T cells targeting B-cell maturation antigen (BCMA), expressed widely on MM cells. To mitigate risks associated with allogenic T cells, we investigated the potential of BCMA CAR expression in natural killer cells (NKs), known for potent cytotoxicity and minimal side effects. Using the NK-92 cell line, we co-expressed BCMA CAR and soluble tumor necrosis factor-related apoptosis-inducing ligand (sTRAIL) employing the PiggyBac transposon system. Engineered NK cells (CAR-NK-92-TRAIL) demonstrated robust cytotoxicity against a panel of MM cell lines and primary patient samples, outperforming unmodified NK-92 cells with a mean difference in viability of 45,1% (± 26,1%, depending on the target cell line). Combination therapy was explored with the proteasome inhibitor bortezomib (BZ) and γ-secretase inhibitors (GSI), leading to a significant synergistic effect in combination with CAR-NK-92-TRAIL cells. This synergy was evident in cytotoxicity assays where a notable decrease in MM cell viability was observed in combinatorial therapy compared to single treatment. In summary, our study demonstrate the therapeutic potential of the CAR-NK-92-TRAIL cells for the treatment of MM. The synergistic impact of combining these engineered NK cells with BZ and GSI supports further development of allogeneic CAR-based products for effective MM therapy.
REVIEW | doi:10.20944/preprints202110.0368.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: chimeric antigen receptors-T cell; solid tumor microenvironment; cancer therapy
Online: 25 October 2021 (15:48:05 CEST)
Findings of new targeted treatments with adequate safety evaluations is essential for better cancer cures and mortality rates. Immunotherapy holds promise for patients with relapsed disease, with the ability to elicit long-term remissions. Emerging promising clinical results in B-cell malignancy using gene-altered T-lymphocytes uttering chimeric antigen receptors have sparked a lot of interest. This treatment could open the path for a major difference in the way we treat tumors that are resistant or recurring. Genetically altered T cells used to produce tumor-specific chimeric antigen receptors are resurrected field of adoptive cell therapy by demonstrating remarkable success in the treatment of malignant tumors. Because of the molecular complexity of chimeric antigen receptors -T cells, a variety of engineering approaches to improve safety and effectiveness are necessary to realize larger therapeutic uses. In this study, we investigate at new strategies for enhancing chimeric antigen receptors-T cell therapy by altering chimeric antigen receptors proteins, T lymphocytes, and their relations with other solid tumor microenvironment (TME) aspects.
ARTICLE | doi:10.20944/preprints202109.0463.v1
Subject: Biology And Life Sciences, Virology Keywords: Artificially designed; chimeric peptides; expression; FMDV; serotype O and A; vaccine candidate
Online: 28 September 2021 (10:56:20 CEST)
Artificially designed, chimeric peptide-based recombinant vaccines are novel approaches to combat the phylogenetically diverse Foot and Mouth Disease (FMD) Virus (FMDV) strains. Among seven distinct serotypes, only serotype O and A are dominantly circulating in Bangladesh and neighbouring countries of Asia, where transboundary transmission, recurrent outbreaks and emergence of novel lineages FMDV are highly prevalent. The objective of this study was to develop multi-epitope recombinant peptides, procuring immunogenicity against circulating diverse subtypes of FMDV serotype O and A. Two chimeric peptides, named B1 (41.0 kDa) and B3 (39.3 kDa), have been designed to incorporate potential B-cell and T-cell epitopes selected from multiple FMDV strains, including previously reported and newly emerged sub-lineages. After expression, characterization and immunization of guineapigs with considerable antigen load of B1 and B3 followed by the serological assays revealed the significant protective immunogenicity, developed from the higher (100 µg) doses of both antigens, against most of the currently prevalent serotype O and A strains of FMDV. The efficient expression, antigenic stability, and multivalent immunogenic potency of the chimeric peptides strongly indicate their credibility as novel vaccine candidates for FMDV serotypes O and A circulating in Bangladesh and surrounding territories.
ARTICLE | doi:10.20944/preprints202102.0579.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Pseudomonas aeruginosa, Reverse vaccinology, Subtractive proteomics, Vaccine candidates, Chimeric vaccine, Druggable targets.
Online: 25 February 2021 (12:06:13 CET)
Pseudomonas aeruginosa is a critical healthcare challenge due to its ability to cause persistent infections and the acquisition of antibiotic resistance mechanisms. Lack of preventive vaccines and rampant drug resistance phenomenon has rendered patients vulnerable. As new antimicrobials are in the preclinical stages of development, mining for the unexploited drug targets is also crucial. Here, we designed a chimeric vaccine against P. aeruginosa using a subtractive proteomics approach and identified nine unique enzymes as novel drug targets in PAO1 proteome. A total of five unique proteins were selected as potential vaccine candidates based on essentiality, extracellular localization, virulence, antigenicity, pathway association, protein-protein interaction analysis, hydrophilicity, and low molecular weight. These include two outer membrane porins OprF (P13794) and OprD (P32722), a protein activator precursor pra (G3XDA9), a probable outer membrane protein precursor PA1288 (Q9I456), and a conserved hypothetical protein PA4874 (Q9HUT9). These proteins were further analyzed using a reverse vaccinology approach to identify immunogenic and antigenic T cell and B cell epitopes. The best scoring epitopes qualifying for all set criteria were then further subjected to the construction of a polypeptide multi-epitope vaccine construct with cholera toxin B (CtxB) subunit as an adjuvant. The identified drug targets qualifying the screening criteria were: UDP-2-acetamido-2-deoxy-d-glucuronic acid 3-dehydrogenase WbpB (G3XD23), aspartate semialdehyde dehydrogenase (Q51344), 2-amino-4-hydroxy-6-hydroxymethyldihydropteridine pyrophosphokinase (Q9HV71), 3-deoxy-D-manno-octulosonic-acid transferase (Q9HUH7), glycyl-tRNA synthetase alpha chain (Q9I7B7), riboflavin kinase/FAD synthase (Q9HVM3), aconitate hydratase 2 (Q9I2V5), probable glycosyltransferase WbpH (G3XD85) and UDP-3-O-[3-hydroxylauroyl] glucosamine N-acyltransferase (Q9HXY6). For druggability and pocketome analysis crystal and homology structures of these proteins were retrieved and developed. A sequence-based search was performed in different databases (ChEMBL, Drug Bank, PubChem and Pseudomonas database) for the availability of reported ligands and tested drugs for the screened targets. These predicted targets may provide a basis for the development of reliable antibacterial preventive and therapeutic options against P. aeruginosa.
ARTICLE | doi:10.20944/preprints202104.0101.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Mouse-Human Chimeric Antibody; Immunotherapy; Infectious diseases; Histoplasmosis; Paracoccidioidomycosis; Histoplasma capsulatum; Paracoccidioides lutzii
Online: 5 April 2021 (11:33:24 CEST)
Heat shock proteins (Hsps) are highly conserved molecules that are constitutively expressed and upregulated in response to physiological stress conditions. These immunogenic chaperones can have essential functions in fungi, particularly in dimorphic pathogens. Histoplasma capsulatum and Paracoccidioides species are dimorphic fungi that are the causative agents of histoplasmosis and paracoccidioidomycosis, respectively, which are systemic mycoses with significant rates of morbidity and mortality. Current treatment consists of long-term antifungal agents, and there is an urgent need for new therapeutic approaches with higher efficacy, lower toxicity, better biodistribution and improved selectivity. We engineered an immunoglobulin G1 (IgG1) isotype chimeric mouse-human monoclonal antibody, titled ch-MAb 4E12, from the parental IgG2a MAb 4E12, a monoclonal antibody to H. capsulatum Hsp60 that is protective in experimental histoplasmosis and paracoccidioidomycosis models elicited by H. capsulatum var. capsulatum and Paracoccidioides lutzii, respectively. The ch-MAb 4E12 increased phagolysosomal fusion and enhanced the yeasts uptake by PMA differentiated human THP1 macrophage cells in vitro. At low concentrations, the chimeric antibody significantly reduced the pulmonary and splenic fungal burden compared to an irrelevant antibody or no treatment. These results are the first to show that a chimeric mouse-human antibody can modify infection caused by dimorphic fungi.
ARTICLE | doi:10.20944/preprints201812.0317.v1
Subject: Biology And Life Sciences, Virology Keywords: universal influenza vaccine; chimeric hemagglutinin; nucleoprotein; live attenuated influenza vaccine; sequential immunization; ferret model
Online: 27 December 2018 (10:14:21 CET)
The development of universal influenza vaccines, i.e. vaccines that can provide broad protection against seasonal and potentially pandemic influenza viruses, has been a priority for more than 20 years. Several approaches have been proposed that redirect the adaptive immune responses from immunodominant hypervariable regions to low-immunogenic but highly conserved regions of viral proteins. Here we induced broadly reactive anti-hemagglutinin (HA) stalk antibody by sequential immunizations with live attenuated influenza vaccines (LAIVs) expressing chimeric HA (cHA). These vaccines contained the HA stalk domain from H1N1pdm09 virus but antigenically unrelated globular head domains from avian influenza viruses H5N1, H8N4 and H9N2. In addition, the source of the viral nucleoprotein (NP) of the LAIV strains was changed from A/Leningrad/17 master donor virus (MDV) to wild-type (WT) H1N1pdm09 virus, in order to induce CD8 T-cell immune responses more relevant to current infections. To avoid any difference in protective effect of the various anti-neuraminidase (NA) antibodies, all LAIVs were engineered to contain the NA gene of Len/17 MDV. Naïve ferrets were immunized with three doses of (i) classical LAIVs containing non-chimeric HA and NP from MDV (LAIVs (NP-MDV)); (ii) cHA-based LAIVs containing NP from MDV (cHA LAIVs (NP-MDV)); and (iii) cHA-based LAIVs containing NP from H1N1pdm09 virus (cHA LAIVs (NP-WT)). A high-dose challenge with H1N1pdm09 virus induced significant pathology in the control, non-immunized ferrets, including high virus titers in respiratory tissues, clinical signs of disease and histopathological changes in nasal turbinates and lung tissues. All three vaccination regimens protected animals from clinical manifestations of disease: immunized ferrets did not lose weight or show clinical symptoms, and their fever was significantly lower than in the control group. Further analysis of virological and pathological data revealed the following hierarchy in the cross-protective efficacy of the vaccines: cHA LAIVs (NP-WT) > cHA LAIVs (NP-MDV) > LAIVs (NP-MDV). This ferret study showed that prototype universal LAIVs that combine the two approaches of inducing anti-HA stalk antibody and more relevant CD8 T-cell immune responses are highly promising candidates for further clinical development.
ARTICLE | doi:10.20944/preprints202212.0234.v1
Subject: Biology And Life Sciences, Virology Keywords: reassortant virus; recombinant virus; chimeric virus; genetic engineering; reverse genetic; SARS-CoV-2; COVID-19
Online: 13 December 2022 (08:47:51 CET)
Due to the fact that to date, the question of the origin of SARS-CoV-2 has not been resolved yet, the author analyzed the main advances in the development of genetic engineering of viruses that took place before the onset of the COVID-19 pandemic. The first artificial genetically modified viruses could appear in nature in the mid-1950s. The technique of nucleic acid hybridization was developed by the end-1960s. In the late 1970s, a method called the "reverse genetics" emerged to synthesize RNA and DNA molecules. In the early 1980-s, it became possible to combine the genes of different viruses and insert the genes of one virus into the genome of another virus. Since that time, the production of vector vaccines began. Currently, by modern technologies one can assemble any virus based on the nucleotide sequence available in the virus database or designed by a computer as a virtual model.Scientists around the world are invited to answer the call of Neil Harrison and Jeffrey Sachs of Columbia University, for a thorough and independent investigation into the origin of SARS-CoV-2. Only a full understanding of the origin of the new virus can minimize the likelihood of a similar pandemic in the future.
ARTICLE | doi:10.20944/preprints202211.0315.v1
Subject: Biology And Life Sciences, Virology Keywords: Tick-borne encephalitis virus; Yellow fever virus; vaccine strain; chimeric virus; infectious subgenomic amplicons; candidate vaccines
Online: 16 November 2022 (16:35:12 CET)
Tick-borne encephalitis virus (TBEV) is one of the most threatening pathogens which affects the human central nervous system (CNS). TBEV circulates widely in Northern Eurasia. According to ECDC the number of TBE cases increase annually. There is no specific treatment for the TBEV infection, thus vaccination is the main preventive measure. Despite the existence of several inactivated vaccines currently being licensed, the development of new TBEV vaccines remains a leading priority in countries endemic to this pathogen. Here we report new recombinant virus made by infectious subgenomic amplicon (ISA) approach using TBEV and yellow fever virus vaccine strain (YF17DD-UN) as a genetic backbone. The recombinant virus is capable of effective replication in mammalian cells and induce TBEV-neutralizing antibodies in mice. Unlike the original vector based on the yellow fever vaccine strain chimeric virus became neuroinvasive in doses of 107-106 PFU and can be used as a model of Flavivirus neuroinvasiveness, neurotropism and neurovirulence. These properties of hybrid structures are the main factors limiting their practical use as vaccines platforms.
REVIEW | doi:10.20944/preprints202207.0256.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: cancer; immunotherapy; adverse events; immune checkpoints inhibitors; chimeric antigen receptor therapy; bispecific antibodies; toxicity; renal; oncology
Online: 18 July 2022 (09:21:56 CEST)
Modern oncological therapy utilizes various types of immunotherapy. Immune checkpoint inhib-itors (ICIs), chimeric antigen receptor T cells (CAR-T) therapy, cancer vaccines and bispecific an-tibodies are improving patients’ outcomes. However, stimulation of the immune system, benefi-cial in terms of fighting against cancer, generates the risk of harm to other cells in a patient's body. Kidney damage belongs to the relatively rare adverse events (AEs). Best described, but still, su-perficially, are renal AEs in patients treated with ICIs. International guidelines issued by Euro-pean Society for Medical Oncology (ESMO) and American Society of Clinical Oncology (ASCO) cover the management of immune-related adverse events (irAEs) during ICI therapy. There are scarce data concerning renal adverse drug reactions of other immunotherapeutic methods. This implicates the need for the collection of safety data during ongoing clinical trials and in the re-al-life world to characterize the hazard related to the use of new immunotherapies and manage-ment of irAEs.
REVIEW | doi:10.20944/preprints202012.0239.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: glioblastoma; high-grade glioma; refractory glioma; virotherapy; oncolytic viruses; neuro-oncology; refractory glioblastoma; chimeric viruses; clinical trials
Online: 9 December 2020 (20:13:56 CET)
As new treatment modalities are being explored in neuro-oncology, viruses are emerging as a promising class of therapeutics. Virotherapy consists of introduction of either wild-type or engineered viruses to the site of disease, where they exert anti-tumor effect. These viruses can either be non-lytic, in which case they are used to deliver gene therapy, or lytic, which induce tumor cell lysis and subsequent host immunologic response. Replication-competent viruses can then go on to further infect and lyse neighboring glioma cells. This treatment paradigm is being explored extensively in both preclinical and clinical studies for a variety of indications. Virus-based therapies are advantageous due to the natural susceptibility of glioma cells to viral infection, which improves therapeutic selectivity. Furthermore, lytic viruses expose glioma antigens to the host immune system and subsequently stimulate an immune response that specifically targets tumor cells. This review surveys the current landscape of oncolytic virotherapy clinical trials in high-grade glioma, summarizes preclinical experiences, identifies challenges associated with this modality across multiple trials, and highlights potential to integrate this therapeutic strategy into promising combinatory approaches.
REVIEW | doi:10.20944/preprints202304.0482.v1
Subject: Medicine And Pharmacology, Hematology Keywords: Acute Myeloid Leukemia, cellular therapies, chimeric antigen T cells, T cell receptor T cells, CAR-NK cells, RNAseq
Online: 18 April 2023 (04:22:46 CEST)
Despite exhaustive studies, researchers have made little progress in the field of adoptive cellular therapies for relapsed-refractory acute myeloid leukemia (AML), unlike the notable uptake for B cell malignancies. Various single antigen targeting chimeric antigen receptor (CAR) T cell Phase I trials have been established worldwide and have recruited approximately 100 patients. The high heterogeneity at the genetic and molecular levels within and between AML patients resembles a black hole: a great gravitational field that sucks in everything, considering only around 30% of patients show a response but with consequential off-tumor effects. It is obvious that a new point of view is needed to achieve more promising results. This review first introduces the unique therapeutic challenges of not only CAR T cells but also other adoptive cellular therapies in AML. Next, recent single cell sequencing data for AML to assess somatically acquired alterations at the DNA, epigenetic, RNA and protein levels are discussed to give a perspective on cellular heterogeneity, intercellular hierarchies, and the cellular ecosystem. Finally, promising novel strategies are summarized, including more sophisticated next-generation CAR T, TCR-T and CAR-NK therapies; approaches to tailor the microenvironment and target neoantigens; and allogeneic approaches.
ARTICLE | doi:10.20944/preprints202204.0072.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: SARS-CoV-2; Variants; COVID-19 vaccine; Chimeric adenovirus-vectored vaccine; GS linker; Neutralizing activity; Th1 immune responses
Online: 8 April 2022 (05:03:04 CEST)
Several COVID-19 platforms have been licensed across the world thus far, but vaccine platforms research that can lead to effective antigen delivery is still ongoing. Here, we constructed AdCLD-CoV19 that could modulate humoral immunity by harboring SARS-CoV-2 antigens onto a chimeric adenovirus 5/35 platform that was effective in cellular immunity. By replacing the S1/S2 furin cleavage sequence of the SARS-CoV-2 Spike (S) protein mounted on AdCLD-CoV19 with the linker sequence, high antigen expression was confirmed in various cell lines. The high levels of antigen expression contributed to antigen-specific antibody activity in mice and non-human primates (NHPs) with single vaccination of AdCLD-CoV19. Furthermore, the adenovirus-induced Th1 immune response was specifically raised for the S protein, and these immune responses protected the NHP against live viruses. While AdCLD-CoV19 maintained neutralizing antibody activity against various SARS-CoV-2 variants, it was reduced to single vaccination for β and ο variants, and the reduced neutralizing antibody activity was restored with booster shots. Hence, AdCLD-CoV19 can prevent SARS-CoV-2 with single vaccination, and the new vaccine administration strategy that responds to various variants can maintain the efficacy of the vaccine.
REVIEW | doi:10.20944/preprints202104.0517.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: CAR T-cells; chimeric antigen receptor T cells; cytokine release syndrome; central nervous system toxicity; neurotoxicity; adverse events; pathophysiology
Online: 19 April 2021 (21:17:34 CEST)
Anti-CD19 chimeric antigen receptor (CAR) T-cells represent a novel immunotherapy that has shown remarkable success in the treatment of adult relapsed or refractory (R/R) B-cell non-Hodgkin's lymphoma, adult R/R mantle cell lymphoma, and R/R acute paediatric lymphoblastic leukaemia. One barrier to the widespread use of CAR T-cell therapy is toxicity, primarily cytokine release syndrome (CRS) with a variable grade of severity. The main manifestations of CRS are fever, hypotension, cytopenia, organ dysfunction among others. Neurological toxicities vary widely and range from headaches to encephalopathy. In addition, anti-CD19 CAR T-cell therapy provokes an array of less frequent events, such as coagulopathies, delayed cytopenia, and cardiovascular toxicities. In general, toxicities are usually reversible and resolve on their own in most cases, though severe cases may require intensive care and immunosuppressive therapy. Deaths due to CRS, neurologic toxicity and infectious complications have been reported, which highlights the gravity of these syndromes and the critical nature of appropriate intervention. In this paper, we look at all available FDA- and EMA-approved information about the pathophysiology, clinical manifestations, risk factor reviews of existing toxicity grading systems, current management strategies, and guidelines for anti-CD19 CAR T-cell toxicities. We also present new approaches, which are under investigation, to mitigate these adverse events.
REVIEW | doi:10.20944/preprints202007.0016.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: myeloma; BCMA; bispecific T-cell engager; antibody-drug conjugates; chimeric antigen receptor T-cells; belantamab mafodotin; idecabtagene vicleucel; JNJ-68284528
Online: 3 July 2020 (07:30:57 CEST)
During the past two decades there has been a major shift in the choice of agents to treat multiple myeloma, whether newly diagnosed or in the relapsed/refractory stage. The introduction of new drug classes, such as proteasome inhibitors, immunomodulators, and anti-CD38 and anti-SLAMF7 monoclonal antibodies, coupled with autologous stem cell transplantation, have approximately doubled the disease’s five-year survival rate. However, this positive news is tempered by the realization that these measures are not curative and patients eventually relapse and/or become resistant to the drug’s effects. Thus, there is a need to discover newer myeloma-driving molecular markers and develop innovative drugs designed to precisely regulate the actions of such putative targets. B cell maturation antigen (BCMA), which is found almost exclusively on the surfaces of malignant plasma cells to the exclusion of other cell types, including their normal counterparts, has emerged as a specific target of interest in this regard. Immunotherapeutic agents have been at the forefront of research designed to block BCMA activity. These agents encompass monoclonal antibodies, such as the drug conjugate belantamab mafodotin; bispecific T-cell engager strategies exemplified by AMG 420; and chimeric antigen receptor (CAR) T-cell therapeutics that include idecabtagene vicleucel (bb2121) and JNJ-68284528.
REVIEW | doi:10.20944/preprints202012.0795.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: T cells; chimeric antigen receptor; transgenic T-cell receptor; tumor-infiltrating lymphocytes; exhaustion; terminal differentiation; senescence; apoptosis; adoptive cell transfer; immunotherapy
Online: 31 December 2020 (12:16:55 CET)
Over the last decades, cellular immunotherapy has revealed its curative potential. However, the inherent physiological characteristics of immune cells can limit the potency of this approach. Best defined in T cells, dysfunction associated with terminal differentiation, exhaustion, senescence, and activation-induced cell death undermine adoptive cell therapies. In this review, we concentrate on how the multiple mechanisms that articulate the various forms of immune dysfunction impact cellular therapies primarily involving conventional T cells, but also other lymphoid subtypes, in addition to the various strategies put in place to circumvent these effects. The repercussions of immune cell dysfunction across the full life cycle of cell therapy, from the source material, during manufacturing, and after adoptive transfer are discussed. Applicable to cellular products prepared from native and unmodified immune cells, as well as genetically engineered therapeutics, the understanding and potential modulation of dysfunctional features is key to the development of improved cellular immunotherapies.