BRIEF REPORT | doi:10.20944/preprints202004.0353.v1
Online: 19 April 2020 (16:54:43 CEST)
We have proposed a model considering two equally sized population (group A and group B) with low and high levels of disease tolerance. We have argued that in the more tolerant group (group B) the progression of the disease with respect to time will be slow with lower number of infections at any given time. We attribute this effect to the innate immunity which advantageously, can also be one of the major contributing factors for flattening the curve. We have compared the growth of Covid-19 disease in various countries to understand this effect.
HYPOTHESIS | doi:10.20944/preprints202006.0178.v1
Subject: Biology, Physiology Keywords: innate immune memory; RNA-i; antiviral immunity; COVID-19; ADE
Online: 14 June 2020 (14:43:09 CEST)
The role of innate immunity in neutralization of viral infections (including COVID-19) and forming long-lasting and specific immune memory is considered. It is assumed that antiviral protection is generated by the mechanism of RNA interference (RNAi) and is based on the presence of specific viral patterns in the DNA library of the host cells.
REVIEW | doi:10.20944/preprints202101.0171.v1
Subject: Life Sciences, Biochemistry Keywords: microgravity; spaceflight; immunology; pathogens; macrophages; bacteria; viruses; innate immune response; adaptive immune response
Online: 11 January 2021 (09:44:52 CET)
Immune dysfunction has long been reported by medical professionals regarding astronauts suffering from opportunistic infections both during their time in space and a short time period afterwards once back on Earth. Various species of prokaryotes on board these space missions or cultured in a microgravity analogue exhibit increased virulence, enhanced formation of biofilms, and in some cases develop specific resistance for specific antibiotics. This poses a substantial health hazard to the astronauts confined in constant proximity to any present bacterial pathogens on long space missions with a finite number of resources including antibiotics. Furthermore, some bacteria cultured in microgravity develop phenotypes not seen in Earth gravity conditions, providing novel insights into bacterial evolution and research.
REVIEW | doi:10.20944/preprints202208.0502.v1
Subject: Life Sciences, Immunology Keywords: Trained immunity; innate immune memory; respiratory pathogens; BCG; next-generation vac-cines; COVID-19
Online: 30 August 2022 (03:55:12 CEST)
The COVID-19 pandemic exposed the vulnerability of current vaccine technologies characterized by a slow onset of action and antigen-specific immune response. Although parental vaccines offer long-term protection against homologous strains, they rely exclusively on adaptive immune memory to produce neutralizing antibodies that are ineffective against new vaccine variants. Moreover, growing evidence highlights the multifaceted functions of trained immunity to elicit a rapid and enhanced innate response against unrelated stimuli or pathogens to subsequent triggers. This review discusses the protective role of trained immunity against respiratory pathogens and the experimental models essential for evaluating novel inducers of trained immunity. We further elaborate on the potential of trained immunity to leverage protection against emerging pathogens via recognition of diverse antigens by pathogen recognition receptors (PPRs) on innate immune cells. We also propose integrating trained- with adaptive- immunity to shape next-generation vaccines by coupling each one's unique characteristics.
REVIEW | doi:10.20944/preprints202209.0487.v2
Subject: Medicine & Pharmacology, Cardiology Keywords: Immunology; innate immunity; immunogenetics; noncoding genome; tRNA biology; evolutionary genetics (list 3-10 specific to the article yet reasonably common within the subject discipline)
Online: 1 November 2022 (09:55:10 CET)
During the past few years unexpected developments have driven studies in the field of clinical immunology. One driver of immense impact was the outbreak of a pandemic caused by the novel virus SARS-CoV-2. Excellent recent reviews address diverse aspects of immunological re-search into cardiovascular diseases. Here, we specifically focus on selected studies taking ad-vantage of advanced state-of-the-art molecular genetic methods ranging from genome-wide epi/transcriptome mapping and variant scanning to optogenetics and chemogenetics. First, we discuss emerging clinical relevance of advanced diagnostics for cardiovascular diseases - includ-ing those associated with COVID-19 - with a focus on the role of inflammation in cardiomyopa-thies and arrhythmias. Second, we consider newly identified immunological interactions at or-gan and systems level which affect cardiovascular pathogenesis. Thus, studies into immune in-fluences arising from the intestinal system are moving towards therapeutic exploitation. Fur-ther, powerful new research tools have enabled novel insight into brain – immune system inter-actions at unprecedented resolution. This latter line of investigation emphasizes the strength of influence of emotional stress - acting through defined brain regions - upon viral and cardiovas-cular disorders. Several challenges need to be overcome before the full impact of these far-reaching new findings will hit the clinical arena.
ARTICLE | doi:10.20944/preprints201906.0028.v1
Subject: Life Sciences, Immunology Keywords: autoimmunity; toll-like receptors; TLR; nucleotide-binding oligomerization domain; NOD1; major histocompatibility complex; MHC; human leukocyte antigens; HLA; proteasome; innate immunity; adaptive immunity; T cells; B cells; antibodies; microbiome; tolerance; self; non-self; antigen processing
Online: 4 June 2019 (10:21:32 CEST)
Current theories of autoimmunity are diverse, sometimes contradictory, and suffer from incompleteness. Although substantial evidence exists that adaptive and innate immunity, sex, genetic predisposition, and the microbiome all play essential roles in autoimmune disease etiologies and pathogenesis, and that antigen processing is altered during disease induction, no existing theory integrates all of these factors through a single, coherent mechanism. In an attempt to focus the field on the need to elucidate such an integrative mechanism, I propose one possibility here that, if nothing else, helps to identify the nature of the problems that need to be addressed. My theory is that autoimmune diseases are induced by normal immunological responses to unique pairs of complementary antigens, at least one of which is a molecular mimic of a host target. Each antigen in the complementary pair induces a complementary immune response (T or B cell); although each immune response is idiotypic in origin, the antigenic complementarity results in what appears to be an idiotype-anti-idiotype relationship between the responses. Additionally, because of the antigenic complementarity, each immune response mimics one of antigens, abrogating the distinction between self and non-self. If at least one of the antigens mimics a host antigen, then the resulting immunological civil war spreads to a host tissue. Complementary antigens also alter antigen processing so that antigens that would normally be proteolytically digested are presented by the major histocompatibility complex (MHC) to T and B cell receptors inducing a cross-reactive immune response. The resulting civil war is supported by the innate immune system due to the complementarity of the initiating antigens.. Complementary antigens stimulate synergistic toll-like receptors (TLR) and/or nucleotide-binding oligomerization receptors (NOD) resulting in up-regulation of cytokine production and further stimulation of the adaptive immune response. Because the immune responses (e.g., antibodies) mimic the initiating antigens, this synergistic activation of innate immunity becomes chronic. Additionally, TLR and NOD function are highly sensitive to sex hormones, some becoming up-regulated and some down-regulated in the presence of either testosterone or estrogens. This sensitivity explains how sex modifies susceptibility to autoimmune diseases. Genetic mutations in TLR, NOD and MHC further alter antigen presentation and the degree to which antigens stimulate an immune response explaining how genetics also modifies susceptibility. Finally, sex hormones also alter the host microbiome, which in turn modulates autoimmune disease risk by shaping the immunological nature of self and by mediating susceptibility to microbial infection. Moreover, it appears that the microbiome camouflages itself from the immune system by mimicking the host antigenic repertoire; the mimicry between the antigens of the microbiome and the host results in selective attacks on microbiome constituents concomitant with any autoimmune attack on host tissues. This antigenic complementarity theory thereby integrates all major elements known to affect, or be affected by, autoimmune diseases and provides a set of testable implications.
ARTICLE | doi:10.20944/preprints202112.0009.v1
Subject: Medicine & Pharmacology, Other Keywords: neutrophils; priming; innate immunity; immune-memory
Online: 1 December 2021 (11:00:01 CET)
Neutrophils as innate immune cells primarily act as first responders in acute infection and directly maintain inflammatory responses. However, a growing body of evidence suggests that neutrophils also bear the potential to mediate chronic inflammation by exhibiting memory-like features. We recently showed that priming by serial doses of lipopolysaccharide (LPS) from gram-negative bacteria can trigger opposing memory-like responses (exaggerated inflammation, i.e. trained sensitivity or suppression of inflammation, i.e. tolerance) depending on the LPS-dose. We now asked whether this observation could also hold true for lipoteichoic acid (LTA) from gram-positive S. aureus. We found comparable effects of LTA on neutrophil priming as seen for LPS. Low-dose (1 ng/mL) LTA-priming promoted increased production of pro-inflammatory mediators (i.e., TNF-α, IL-6, ROS), whereas high-dose (10 µg/mL) results in contrary reactions supporting anti-inflammatory responses by increased IL-10 and declined pro-inflammatory capacity. In vitro neutrophil recruitment was similarly regulated by LTA -priming. Investigation of signalling patterns revealed TLR2/MyD88-mediated regulation of NFκB-p65 through intermediate PI3Ks/MAPK. Collectively, our data suggest a previously unknown capacity of neutrophils to be differentially primed by varying doses of LTA, endorsing memory-like features in neutrophils.
REVIEW | doi:10.20944/preprints201910.0282.v1
Subject: Medicine & Pharmacology, Gastroenterology Keywords: liver fibrosis; NASH; innate immune cells.
Online: 24 October 2019 (15:48:02 CEST)
Nonalcoholic steatohepatitis (NASH), which is characterized by liver steatosis, inflammation and fibrosis, is the most severe variation of nonalcoholic fatty liver disease (NAFLD). This disease is a consequence of several metabolic alterations such as type 2 diabetes and dyslipidemia that trigger different pathways of cell dysfunction and systemic inflammation which ultimately affect the liver. Furthermore, those mechanisms activate a complex cascade of immune response after repeated cell aggression. In the liver cytokines and interleukins interact with network of innate immune cells, including Kupffer cells (KCs), dendritic cells (DCs), lymphocytes and hepatic stellate cells (HSC). These cells translate those signals into immune responses and pathologic hepatic changes during the development of NASH. In this scenario the development of fibrosis is the most important change since it is an adaptive mechanism that in the short time has the objective of repair the damaged tissue but after prolonged injury it progresses to parenchymal scarring, cellular dysfunction and finally to organ failure. Finally, since NASH is an important cause of liver cirrhosis; this review addresses the cellular pathways of fibrosis in the setting of NASH explained by the interaction between immune and hepatic cells.
REVIEW | doi:10.20944/preprints202105.0625.v1
Online: 26 May 2021 (08:17:01 CEST)
Toll-like receptors (TLRs) are a class of pattern recognition receptors (PRRs) family that identify pathogen-associated molecular patterns derived from microbes and activate immune cell response. Following TLRs ligation, different adaptor and transcription molecules such as myeloid differentiation primary response gene 88 (MyD88) and nuclear factor kappa B (NF-kB) are recruited that initiate inflammatory signaling pathways. The human Toll-like receptor 10 (hTLR10) is a novel member of the PRRs family with a regulatory function of immune responses because of unique cytoplasmic domains which lead to induction of both inflammatory and anti-inflammatory properties. Recent studies have reported the association of TLR10 polymorphisms with many inflammatory diseases and human cancer. Engagement of TLR10 on the surface of the epithelium and macrophages leads to the production of proinflammatory cytokines and chemokines, while other studies have proven an anti-inflammatory role of TLR10. Accordingly, TLR10 suppresses proinflammatory cytokine production via negative regulation of MyD88 and the Akt (protein kinase B) and MAPK (mitogen-activated protein kinase) signaling pathways. This review aimed to provide answers for these conflicting findings (Inflammatory and anti-inflammatory properties of TLR10) to further identify distinct biological functions of TLR10.
REVIEW | doi:10.20944/preprints202011.0477.v1
Subject: Keywords: Multiple Sclerosis, Experimental Autoimmune Encephalomeylitis, Adaptive Immunity, Innate Immunity
Online: 18 November 2020 (12:50:18 CET)
Multiple sclerosis (MS) is a chronic autoimmune disease that affects the central nervous system (CNS) characterized by varying degrees of demyelination of uncertain etiology, and is associated with specific environmental and genetic factors. Upon recognition of CNS antigens, the immune cells initiate an inflammatory process which leads to destruction and deterioration of the neurons. Innate immune cells such as macrophages, dendritic cells and natural killer cells are known to play critical roles in the pathogenesis of MS. Also, the activation of peripheral CD4+ T cells by CNS antigens leads to their extravasation into the CNS causing damages that exacerbates the disease. This could be accompanied by dysregulation of T regulatory cells and other cell types functions. Experimental autoimmune encephalomyelitis (EAE) is a mouse model used to study the pathophysiology of MS disease. In this review, we highlight the roles of innate and adaptive immune players in the pathogenesis of MS and EAE.
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: COVID-19; Inflammasome; Interleukin 1β; Inflammation; Innate Immune System
Online: 12 July 2020 (08:17:56 CEST)
Covid-19 disease is caused by SARS Cov-2 virus. Despite its high transmissibility, the CFR (Case Fatality Rate) of COVID-19 seems to be lower than the SARS (9,5%) and MERS (34,4%) ones93 , but higher than the influenza one (0-1%)94,95 . The disease is asymptomatic or paucisymptomatic in most of the patients, although in few cases it can be characterized by serious complications. The main causes of hospitalization in intensive care are represented by ALI (Acute Lung Injury), ARDS (Acute Respiratory Distress Syndrome), cardiovascular problems and coagulopathies (diffuse thrombosis, microthrombosis, embolisms, myocarditis, arrhytmias, heart failure, stroke)96-98, acute nephropathy99,100 and encephalopathies101. The virus presence in the vascular wall can cause endotheliitis, which triggers the process of diffuse coagulation that can lead to a worsening of the systemic inflammation. The exaggerated inflammatory response seems to be connected with the development of ARDS, MOF (Multiple Organ Failure) and coagulopathies102-107.
REVIEW | doi:10.20944/preprints202004.0238.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: Covid; NET; neutrophils; circulating DNA; therapy; innate immune response
Online: 15 April 2020 (09:55:34 CEST)
Neutrophils play an important role as the first line of innate immune defense. One function of neutrophils, called neutrophil extracellular traps (NETs), has been discovered recently. NETs are extensive fibrous structures released extracellularly from activated neutrophils in response to infection. They are composed of cytosolic protein assembled on a scaffold of released chromatin. These structures suppress the dissemination of micro-organisms in blood by trapping them mechanically, and by exploiting coagulant function to segregate them within the circulation. In addition, NET components (DNA, histone, and granule proteins) also contribute to the triggering of an inflammatory process. NET function, however, can be regarded as a double-edged sword. On one hand, NET formation is an efficient strategy for neutralizing invading micro-organisms. On the other hand, NET can be harmful to the host, as its exposed by-products that are toxic to endothelial cells and parenchymal tissue. We present here the analogous biological and physiological features of the harmful positive amplification loop between inflammation and tissue damage induced by NETosis dysregulation and Coronavirus Disease-2019 (COVID-19) pathogenesis. Considering the rapid evolution of this disease symptoms and its lethality, we hypothesize that COVID-19 progresses under an amplifier loop, leading to an massive, uncontrolled inflammation process. We also describe the correlations of COVID-19 symptoms and biological features with those consecutive to uncontrolled NET formation causing various sterile or infectious diseases. General clinical conditions, and numerous pathological and biological features, are analogous with NETs deleterious effects. We postulate that Severe Acute Respiratory Syndrome-Coronavirus 2 (SARS-CoV2) induces a disproportionate virus-induced NET release, and that this plays a key role in COVID-19 pathogenesis. While neutrophils are the principal starting point for extracellular and circulating DNA release, targeting NETs rather than neutrophils themselves may stand for an effective strategy. This paper offers an in-depth review of NET formation, function and pathogenic dysregulation, as well as of current and future therapies to control NET unbalance. As such, it enables us also to suggest new therapeutic strategies to fight COVID-19. In combination with or independent of the latest tested approaches, we propose that, in the short term, deoxyribonuclease I (DNase-1) treatment should be evaluated; we also advocate a significant increase in research on the development of toll-like receptors (TLR) and C-type Lectin like receptors (CLEC) inhibitors, and on anti-IL26 therapies.
ARTICLE | doi:10.20944/preprints201807.0522.v1
Subject: Biology, Plant Sciences Keywords: DAMPs; alarmins; innate immune response; plants; phylogeny; in silico
Online: 26 July 2018 (16:08:54 CEST)
In plants and animals, endogenous biological molecules, termed damage-associated molecular patterns (DAMPs) or alarmins, are released by damaged, stressed or dying cells following abiotic stress such as radiation and drought stress. In turn, a cascade of downstream signaling events is initiated leading to the up-regulation of defense-related genes. In the present study, in an effort to investigate the conservation status of the molecular mechanisms implicated in the danger signaling, thorough in silico phylogenetic and structural analyses of the effector biomolecules were performed in taxonomically diverse plant species. On the basis of our results, the defense mechanisms appear to be largely conserved within the plant kingdom. Of note is our finding that the sequence and/or function of several components of these mechanisms were found to be conserved in animals, as well.
REVIEW | doi:10.20944/preprints201705.0209.v2
Subject: Life Sciences, Immunology Keywords: influenza virus; apoptosis; antiviral agent; innate immunity; host response
Online: 14 August 2017 (04:41:22 CEST)
Human influenza A viruses (IAVs) cause global pandemics and epidemics, which remain serious threats to public health because of the shortage of effective means of control. To combat the surge of viral outbreaks, new treatments are urgently needed. Developing new virus control modalities requires better understanding of virus-host interactions. Here we describe how IAV infection triggers cellular apoptosis, and how this process can be exploited towards development of new therapeutics, which might be more effective than the currently available anti-influenza drugs.
REVIEW | doi:10.20944/preprints202104.0036.v1
Subject: Life Sciences, Biochemistry Keywords: mast cells; innate immunity; host defense; skin; inflammatory skin disorders
Online: 1 April 2021 (17:44:17 CEST)
Mast cells (MCs) are best known as key effector cells of immediate type allergic reactions that may even culminate in life-threatening anaphylactic shock syndromes. However, strategically positioned at host-environment interfaces and equipped with a plethora of receptors, MCs also play an important role in the first line defense against pathogens. Their main characteristic, the huge amount of preformed pro-inflammatory mediators embedded in secretory granules, allow for a rapid response and initiation of further immune effector cell recruitment. The same mechanism, however, may account for detrimental overshooting responses. MCs are not only detrimental in MC-driven diseases, but also responsible for disease exacerbation in other inflammatory disorders. Focusing on the skin as the largest immune organ, we herein review both beneficial and detrimental functions of skin MCs all the way from skin barrier integrity via host defense mechanisms to MC-driven inflammatory skin disorders. Moreover, we emphasize the importance of IgE-independent pathways of MC activation and their role in sustained chronic skin inflammation and disease exacerbation.
Subject: Biology, Anatomy & Morphology Keywords: RSV; BRD4; AP-MS; PPI; AP1; Wnt; Innate Immune Response
Online: 26 February 2021 (09:26:24 CET)
Respiratory Syncytial Virus (RSV) causes severe inflammation and airway pathology in children and the elderly by infecting the epithelial cells of the upper and lower respiratory tract. RSV replication is sensed by intracellular pattern recognition receptors upstream of the IRF and NF-B transcription factors. These proteins coordinate an innate inflammatory response via Bromodomain containing protein 4 (BRD4), a protein that functions as a scaffold for unknown transcriptional regulators. To better understand the pleiotropic regulatory function of BRD4, we examine the BRD4 interactome and identify how RSV infection dynamically alters it. To accomplish these goals, we leverage native immunoprecipitation and Parallel Accumulation – Serial Fragmentation (PASEF) mass spectrometry to examine BRD4 complexes isolated from human alveolar epithelial cells in the absence or presence of RSV infection. In addition, we explore the role of BRD4’s acetyl-lysine binding bromodomains in mediating these interactions by using a highly selective competitive bromodomain inhibitor. We identify 101 proteins that are significantly enriched in the BRD4 complex and are responsive to both RSV-infection and BRD4 inhibition. These proteins are highly enriched in transcription factors and transcriptional coactivators. Among them, we identify members of the AP1 transcription factor complex, a complex important in innate signaling and cell stress responses. We independently confirm the BRD4/AP1 interaction in primary human small airway epithelial cells. We conclude that BRD4 recruits multiple transcription factors during RSV infection in a manner dependent on acetyl-lysine binding domain interactions. This data suggests that BRD4 recruits transcription factors to target its RNA processing complex to regulate gene expression in innate immunity and inflammation.
ARTICLE | doi:10.20944/preprints201905.0290.v1
Subject: Life Sciences, Immunology Keywords: β-D-glucan; glucan binding protein; host defense; innate immunity
Online: 24 May 2019 (08:56:43 CEST)
The recognition of (1→3)-β-D-glucans (BGs) by β-1,3-D-glucan recognition protein (BGRP) found in invertebrates plays a significant role in the activation of toll pathway and pro-phenol oxidase system in insect host defense against fungal invasion. To examine the structural diversity of BGs in BGRP interaction, the binding specificity of BGRPs cloned from four different insectswas characterized using ELISA. Recombinant BGRPs expressed as Fc-fusion proteins of human IgG1 bound to solid phase BGs. Because of the binding specificities, the BGRPs were categorized into two different ultrastructure- binding characters. The BGRPs from Silkworm and Indian meal moth bound to BGs containing triple-helical structure. Other BGRPs from red flour beetle and yellow mealworm beetle showed no binding to triple-helical BGs, but to alkaline-treated BGs, which have partially opened helical conformation. These evidences suggest that the innate immune system distinguishes different BG conformations and it is equipped for the diversity of BG structures.
REVIEW | doi:10.20944/preprints201811.0350.v1
Subject: Life Sciences, Immunology Keywords: mannose-binding lectin; poultry; production system; pathogens; innate immune response
Online: 15 November 2018 (08:37:05 CET)
Bacterial pathogens have been attributed to poultry housing structure, financial strength, and incessant use of antibiotics, variable seasons and management systems practiced. Variant forms of bacterial pathogens can be detected by recognizing the molecular pattern of the pathogens through an innate immune mechanism such as mannose-binding lectin. Mannose-binding lectin (MBL) possesses an innate pattern recognition molecule that easily sequestered to region of infections and inflammations. This works by attaching itself to antigen surface thus hinders proliferation and disease activity in the host organism. Baker’s method, nephelometric assays technique, Enzyme-Linked Immunosurbent Assay technique, Polymerase Chain Reaction, Deoxyribonucleic Acid typing and other biotechnology related methods are techniques used in detecting and quantifying MBL. Mannose-binding lectin levels in serum can be influenced by age, management systems, feed formulation strategies and seasons. Therefore, knowledge of MBL should be encouraged in all aspect of poultry production, in order to discourage incessant use of drugs at a slight exposure to prevailing bacterial which can help in maximizing cost.
ARTICLE | doi:10.20944/preprints202108.0494.v1
Subject: Life Sciences, Immunology Keywords: Glioblastoma; immunogenic cell death; innate immunity; natural Killer; macrophages; magnetic hyperthermia
Online: 25 August 2021 (13:45:34 CEST)
Cancer immunotherapies are gaining a large popularity and many of them have been approved as standard second-line or in some cases even as first-line treatment for a wide range of cancers. However, immunotherapy has not shown a clinically relevant success in glioblastoma (GBM), principally due to the brain’s “immune-privileged” status and the peculiar tumor microenvironment (TME) of GBM featured by lack of presence of tumor-infiltrating lymphocytes and the establishment of immunosuppressive mechanisms. Emerging evidence has highlighted the key role played by innate immune cells in immunosurveillance and in initiating and driving immune responses against GBM. Immunogenic cell death (ICD) is a promising approach to elicit direct activation of the innate immune system by inducing in target cancer cells the expression of molecular signatures recognized through a repertoire of innate immune cell pattern recognition receptors (PRRs) by effector innate immune cells. Herein, we explored local mild thermal treatment, generated by using ultrasmall (size ~ 17 nm) cubic-shaped iron oxide nanoparticles exposed to an external alternating magnetic field (AMF), to induce ICD in U87 glioblastoma cells. In accordance with what has been previously observed with other types of tumors, we found that mild hyperthermia modulates the immunological profile of U87 glioblastoma cells by inducing stress-associated signals leading to enhanced phagocytosis and killing of U87 cells by macrophages. Finally, we demonstrated that mild magnetic hyperthermia has a modulatory effect on the expression of inhibitory and activating NK cell ligands on target cells. Interestingly, alteration in the expression of NK ligands, caused by mild hyperthermia treatment, in U87 glioblastoma cells, increased their susceptibility to NK cell killing and NK cell functionality. The overall findings demonstrate that mild magnetic hyperthermia stimulates ICD and sensitizes GBM cells to NK-mediated killing by inducing the upregulation of specific stress ligands, providing a novel immunotherapeutic approach for GBM treatment, with potential to synergize with existing NK cell-based therapies thus improving their therapeutic outcomes.
ARTICLE | doi:10.20944/preprints202102.0215.v1
Subject: Life Sciences, Biochemistry Keywords: Insect-specific flavivirus; CpG; Dinucleotides; Innate immunity; Zinc-finger antiviral protein
Online: 8 February 2021 (15:46:14 CET)
The genus Flavivirus contains pathogenic vertebrate-infecting flaviviruses (VIFs) and in-sect-specific flaviviruses (ISF). ISF transmission to vertebrates is inhibited at multiple stages of the cellular infection cycle, via yet to be elucidated specific antiviral responses. The Zinc-finger an-tiviral protein (ZAP) in vertebrate cells can bind CpG dinucleotides in viral RNA, limiting virus replication. Interestingly, the genomes of ISFs contain more CpG dinucleotides compared to VIFs. In this study, we investigated whether ZAP prevents two recently discovered lineage II ISFs, Binjari (BinJV) and Hidden Valley viruses (HVV) from replicating in vertebrate cells. BinJV protein and dsRNA replication intermediates were readily observed in human ZAP knockout cells when cultured at 34 ˚C. In ZAP expressing cells, inhibition of the interferon response via interferon response factors 3/7 did not improve BinJV protein expression, whereas treatment with kinase inhibitor C16, known to reduce ZAP’s antiviral function, did. Importantly, at 34 ˚C both BinJV and HVV successfully completed the infection cycle in human ZAP knockout cells evident from infectious progeny virus in the cell culture supernatant. Therefore, we identify vertebrate ZAP as an important barrier that protects vertebrate cells from ISF infection This provides new insights into flavivirus evolution and the mechanisms associated with host switching.
REVIEW | doi:10.20944/preprints202006.0159.v1
Online: 14 June 2020 (03:18:35 CEST)
Novel coronavirus disease (COVID-19) has affected nearly 7 million individuals and claimed more than 0.4 million lives to date. There are several reports of gender differences related to infection and death due to COVID-19. This raises important questions such as “Whether there are differences based on gender in risk and severity of infection or mortality rate?” and “What are the biological explanation and mechanisms underlying these differences?” Emerging evidence has proposed sex-based immunological, genetic, and hormonal differences to explain this ambiguity. Besides biological differences, women have also faced social inequities and economic hardships due to this pandemic. Several recent studies have shown that independent of age males are at higher risk for severity and mortality in COVID-19 patients. Although susceptibility to SARS-CoV-2 was found to be similar across both genders in several disease cohorts, a disproportionate death ratio in men can be partly explained by the higher burden of pre-existing diseases and occupational exposures among men. From an immunological point of view, females can engage a more active immune response, which may protect them and counter infectious diseases as compared to men. This attribute of better immune responses towards pathogens is thought to be due to high estrogen levels in females. Here we review the current knowledge about sex differences in susceptibility, the severity of infection and mortality, host immune responses, and the role of sex hormones in COVID-19 disease.
ARTICLE | doi:10.20944/preprints202105.0297.v1
Subject: Life Sciences, Biochemistry Keywords: Protein Kinase Receptor (PKR); Mammarenavirus; Interferon; Innate immune response; Mx1; ISG15; CCL5
Online: 13 May 2021 (13:27:07 CEST)
The New World (NW) mammarenavirus group includes several zoonotic highly pathogenic viruses, such as Junin (JUNV) or Machupo (MACV). Contrary to Old World mammarenavirus, these viruses are not able to completely suppress the innate immune response, and trigger a robust interferon (IFN)-I response via retinoic acid-inducible gene I (RIG-I). Nevertheless, pathogenic NW mammarenaviruses trigger a weaker IFN response than their non-pathogenic relatives do. RIG-I activation leads to upregulation of a plethora of IFN-stimulated genes (ISGs), which exert a characteristic antiviral effect either as lone effectors, or resulting from the combination with other ISGs or cellular factors. The dsRNA sensor-protein kinase receptor (PKR) is an ISG that plays a pivotal role in the control of the mammarenavirus infection. In addition to its well-known protein synthesis inhibition, PKR further modulates the overall IFN-I response against different viruses, including mammarenaviruses. For this study, we employed Tacaribe virus (TCRV), the closest relative of the human pathogenic JUNV. Our findings indicate that PKR does not only increase IFN-I expression against TCRV infection, but also affects the kinetic expression and the extent of induction of Mx1 and ISG15 at both levels, mRNA and protein expression. Moreover, TCRV fails to prevent the effect of PKR on viral protein translation and its viral titer is inhibited when PKR is pre-stimulated via IFN-I. Here, we provide first evidence of the specific immunomodulatory role of PKR over selected ISGs, altering the dynamic of the innate immune response course against TCRV. IMPORTANCE: The mechanisms for innate immune evasion are key for emergence and adaptation of human pathogenic arenaviruses, and highly pathogenic mammarenaviruses such as JUNV or MACV trigger a weaker IFN response than non-pathogenic mammarenaviruses. Within the innate immune response context, PKR plays an important role in sensing and restricting the infection of TCRV virus. Although the mechanism of PKR for protein synthesis inhibition is well described, its immunomodulatory role is less understood. In this study, we found that TCRV protein expression and viral propagation are inhibited from early times after infection, and when externally activated, PKR inhibits TCRV viral progeny production. Our present findings further characterize the innate immune response in absence of PKR, unveiling the role of PKR in defining the ISG profile after viral infection.
REVIEW | doi:10.20944/preprints202011.0053.v1
Subject: Life Sciences, Biochemistry Keywords: Mast cells; innate immunity; adaptive immunity; wound healing; Immunoglobin E; vaccine adjuvants
Online: 2 November 2020 (14:59:10 CET)
Mast cells are long-lived, granular, myeloid-derived leukocytes that have significant protective and repair functions in tissues. Mast cells sense disruptions in the local microenvironment and are first responders to physical, chemical and biological insults. When activated, mast cells release growth factors, proteases, chemotactic proteins and cytokines thereby mobilizing and amplifying the innate and adaptive immune system. Mast cells are therefore significant regulators of homeostatic functions and may be essential in microenvironmental changes during pathogen invasion and disease. During infection by helminths, bacteria and viruses, mast cells release antimicrobial factors to facilitate pathogen expulsion and eradication. Mast cell-derived proteases and growth factors protect tissues from insect/snake bites and exposure to ultraviolet radiation. Finally, mast cells release mediators that promote wound healing in the inflammatory, proliferative and remodeling stages. Since mast cells have such a powerful repertoire of functions, targeting mast cells may be an effective new strategy for immunotherapy of disease and design of novel vaccine adjuvants. In this review, we will examine how certain strategies that specifically target and activate mast cells can be used to treat and resolve infections, augment vaccines and heal wounds. Although these strategies may be protective in certain circumstances, mast cells activation may be deleterious if not carefully controlled and any therapeutic strategy using mast cell activators must be carefully explored.
REVIEW | doi:10.20944/preprints201807.0013.v1
Subject: Life Sciences, Virology Keywords: viral dissemination; innate immune cells; cytomegalovirus; pathogenesis; chemokines; Fenner hypothesis; neutrophils; monocytes
Online: 2 July 2018 (13:14:05 CEST)
Human cytomegalovirus (HCMV) is a β-herpes virus that is a significant pathogen within immune compromised populations. HCMV morbidity is induced through viral dissemination and inflammation. Typically, viral dissemination is thought to follow Fenner’s hypothesis where virus replicates at the site of infection, followed by replication in the draining lymph nodes, and eventually replicating within blood filtering organs. Although CMVs somewhat follow Fenner’s hypothesis, they deviate from it by spreading primarily through innate immune cells as opposed to cell free virus. Also, in vivo CMVs infect new cells via cell to cell spread and disseminate directly to secondary organs through novel mechanisms. We review the historic and recent literature pointing to CMV’s direct dissemination to secondary organs and the genes that it has evolved for increasing its ability to disseminate. We also highlight aspects of CMV infection for studying viral dissemination when using in vivo animal models.
REVIEW | doi:10.20944/preprints202209.0076.v1
Subject: Life Sciences, Immunology 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/preprints202007.0618.v1
Subject: Life Sciences, Immunology Keywords: Innate immune memory; inflammatory response; β-glucan; flow cytometry; primary chicken monocytes; macrophages
Online: 25 July 2020 (18:00:05 CEST)
Beta-glucan-stimulated mammalian macrophages show an increased responsiveness to secondary stimulation in a nonspecific manner. This phenomenon is known as trained innate immunity. Our study aimed to explore training of primary chicken monocytes. We hypothesized that primary chicken monocytes, similar to their mammalian counterparts, can be trained with β-glucan resulting in increased responses of these cells to a secondary stimulus. Primary blood monocytes of white leghorn chickens were primary stimulated with β-glucan microparticulates (M-βG), LPS, recombinant chicken interleukin-4 (IL-4) or combinations of these components for 48 h. On day 6, the primary stimulated cells were secondary stimulated with LPS. Nitric oxide (NO) production levels were measured as an indicator of pro-inflammatory activity. In addition, the cells were analysed by flow cytometry to characterize the population of trained cells and to investigate the expression of surface markers associated with activation. After the secondary LPS stimulation, surface expression of CSF1R and the activation markers CD40 and MHC-II was higher on macrophages that were trained with a combination of M-βG and IL-4 compared to unstimulated cells. This increased expression was paralleled by enhanced NO production. In conclusion, this study showed that trained innate immunity can be induced in primary chicken monocytes with β-glucan, which is in line with previous experiments in mammalian species. Innate immune training may have potential to improve health and vaccination strategies within the poultry sector.
REVIEW | doi:10.20944/preprints201903.0231.v1
Subject: Earth Sciences, Environmental Sciences Keywords: cyanotoxin; cyanobacterial bloom; cylindrospermopsin; microcystin; inflammation; diarrhea; gastrointestinal illness; lipopolysaccharide; innate immune system
Online: 26 March 2019 (09:31:44 CET)
Cyanobacterial blooms occur with increasing frequency in freshwater ecosystems, posing a hazard to human and environmental health. Exposure of human to cyanobacterial metabolites occurs mostly via accidental ingestion through contaminated drinking water or during recreational activities and, most frequently, results in gastrointestinal symptoms. Despite the clinical manifestation, cyanobacterial metabolites are rather investigated for their toxicity towards specific organs or tissues, especially hepato-, nephro- and neurotoxicity, then for effects on the gastrointestinal tract and the associated lymphoid tissue. The aim of this review was to systematically summarize available literature on the effects on the gastrointestinal tract and the mucosal innate immune system and compile the data from both, in vitro and in vivo studies, focusing on human-health relevant models. Our systematic literature review revealed significant data gaps in the understanding on metabolites breaching the gastrointestinal barrier and the role of the immune system in the establishment of clinical symptoms. Microcystins and cylindrospermopsin were linked to gastrointestinal symptoms, immune system effects or both. Furthermore, implications for cyanobacterial bloom lipopolysaccharides in gastrointestinal inflammation were reported in several cases, while other metabolites received only minor attention. The collected data indicate the need for a reassessment of potential enterotoxicity of microcystins and cylindrospermopsin. Additionally, the carcinogenic potential of cyanotoxins, especially microcystins, has to be clarified, as an increasing amount of epidemiological studies show correlations between cyanobacterial blooms and gastrointestinal cancer incidence. Furthermore, other, often highly abundant bioactive metabolites like aeruginosins, have to be toxicologically evaluated at levels also accounting for (sub-)chronic exposure to low concentrations and in combination with naturally co-occurring metabolites, as can be expected in drinking water supplies. studies, focusing on human-health relevant models. Our systematic literature review revealed significant data gaps in the understanding on metabolites breaching the gastrointestinal barrier and the role of the immune system in the establishment of clinical symptoms. Microcystins and cylindrospermopsin were linked to gastrointestinal symptoms, immune system effects or both. Furthermore, implications for cyanobacterial bloom lipopolysaccharides in gastrointestinal inflammation were reported in several cases, while other metabolites received only minor attention. The collected data indicate the need for a reassessment of potential enterotoxicity of microcystins and cylindrospermopsin. Additionally, the carcinogenic potential of cyanotoxins, especially microcystins, has to be clarified, as an increasing amount of epidemiological studies show correlations between cyanobacterial blooms and gastrointestinal cancer incidence. Furthermore, other, often highly abundant bioactive metabolites like aeruginosins, have to be toxicologically evaluated at levels also accounting for (sub-)chronic exposure to low concentrations and in combination with naturally co-occurring metabolites, as can be expected in drinking water supplies.
ARTICLE | doi:10.20944/preprints201809.0525.v1
Subject: Life Sciences, Virology Keywords: hepatitis E virus; innate immunity; interferon response; JAK/STAT pathway; zoonosis; emerging pathogen
Online: 27 September 2018 (03:34:49 CEST)
Hepatitis E virus (HEV) is responsible for large waterborne epidemics of hepatitis in endemic countries and is an emerging zoonotic pathogen worldwide. In endemic regions, HEV-1 or HEV-2 genotypes are frequently associated with fulminant hepatitis in pregnant women, while with zoonotic HEV (HEV-3 and HEV-4), chronic cases of hepatitis and severe neurological disorders are reported. Hence, it is important to characterize the interactions between HEV and its host. Here, we investigated the ability of the non-structural polyprotein encoded by the first open reading frame (ORF1) of HEV to modulate the host early antiviral response and in particular the type I interferon (IFN-I) system. We found that the amino-terminal region of HEV-3 ORF1 (MetPCP), containing a putative methyltransferase (Met) and a papain-like cysteine protease (PCP) functional domain, inhibited IFN-stimulated response element (ISRE) promoter activation and the expression of several IFN-stimulated genes (ISGs) in response to IFN-I. We showed that the MetPCP domain interfered with the Janus kinase (JAK)/signal transducer and activator of transcription protein (STAT) signalling pathway by inhibiting STAT1 nuclear translocation and phosphorylation after IFN-I treatment. By contrast, MetPCP had no effect on STAT2 phosphorylation and a limited impact on the activation of the JAK/STAT pathway after IFN-II stimulation. This inhibitory function seemed to be genotype-dependent as MetPCP from HEV-1 had no significant effect on the JAK/STAT pathway. Overall, this study provides evidence that the predicted MetPCP domain of HEV ORF1 antagonises STAT1 activation to modulate the IFN response.
BRIEF REPORT | doi:10.20944/preprints202005.0515.v1
Subject: Life Sciences, Virology Keywords: Covid-19; Herd Immunity Threshold; Corona Virus; Innate immunity; flattening the curve; serological survey
Online: 31 May 2020 (21:14:05 CEST)
We have analysed the death and recovery rate of Covid-19 disease progression. From the analysis, we have argued that the pandemic is over in certain countries (labelled as group-A) and for other countries (labelled as group-B) the disease appears to remain as endemic. Taking into account the serological survey (sero-survey) test results obtained by certain groups and comparing it with herd immunity threshold value one can infer that the low number of infection for group-B is either due to acquired immunity by some previous infection by other coronavirus or due to innate immunity towards this infection. This effect is stronger for group-B to slow the progress of the disease to such an extent resulting in flattening of the disease progression curve compared to group-A.
ARTICLE | doi:10.20944/preprints201911.0329.v1
Subject: Medicine & Pharmacology, Other Keywords: Vibrio cholerae cytotoxin; VCC; MAPKs; p38; ERK; pro-inflammatory; innate immune response; survival response
Online: 27 November 2019 (04:33:42 CET)
The human innate immune response to the pore-forming toxin of Vibrio cholerae VCC, is currently under study. Here, in vitro studies on a human macrophage cell line (THP-1), helped explore the activated pathways involved on the onset the innate immune response towards the cytotoxin. The secreted monomeric 65 KDa form interacts with mature macrophages in pg/ml concentrations, determined by dose response experiments after treatments under 1 h. Non vacuolating concentrations (pg/ml) were applied to the cells; immunoblots revealed activation of MAPKs: early overexpression of p38 and ERK. Cell lysis by release of lactate dehydrogenase (LDH) was not apparent in the first hour, nonetheless it was positive after 24 h. Finally, to discern whether the VCC stimulates transcriptional activators via MAPKs pathway, NF-κB and AP-1 were studied by real time quantitation. Increased expression of p50 (NF-κB), cJun and cFos (AP-1) was observed. Given that NF-κB is the transcription factor initiating inflammation of innate immune response and in turn, AP-1 is responsible for cell surviving response, results from this study lead us to conclude that VCC in vitro treatments, induce a pro-inflammatory and a surviving response, in less than one hour on activated macrophages.
ARTICLE | doi:10.20944/preprints201904.0148.v1
Subject: Life Sciences, Immunology Keywords: chronic hepatitis C; chronic hepatitis B; innate immune response; adaptive immune response; cytokine; chemokine
Online: 12 April 2019 (10:59:21 CEST)
Background: Cytokines and chemokines are critical regulators of innate and adaptive immunities during viral infection. We examined innate and adaptive immune responses to hepatitis C virus (HCV) and hepatitis B virus (HBV) at baseline and against controls. Methods: Twenty-seven cytokines were evaluated before treatment in 27 patients with chronic hepatitis C(CHC) [genotype1 (n=20), genotype2 (n=7), HCVRNA 5.72IU/ml] and 12 chronic hepatitis B(CHB) [e-antigen (Ag) (+) (n=5), e-Ag (-) (n=7), HBVDNA 6.191.31Logcopies/ml] and against controls(n=5). Results: Th1 and Th2 cytokines were significantly higher (p<0.05) in CHB than in CHC. The levels of IL-IL10 in CHC and CHB, and IL15 in CHC(genotype2) and CHB were significantly lower (p<0.05) than in controls. The levels of CXCL8 in CHC and CHB, IL12 in CHC and CHB [e-Ag (-)] and CXCL10 in CHC and CHB were significantly higher (p<0.05) than in controls. IFN-γwas higher in CHB than in controls. Conclusion: Cytokines levels differed between CHB and CHC before treatment. Innate immune responses were impaired in CHB with HBeAg(-) and CHC, but not in CHB with HBeAg(+) with high viral loads. Adaptive immune responses were impaired in CHB and CHC and appear to reflect the distinct state of virus-host immune interactions between CHB and CHC.
REVIEW | doi:10.20944/preprints201807.0518.v1
Subject: Life Sciences, Virology Keywords: virus; antiviral agent; drug target; drug side effect; innate immunity; precision medicine; systems biology
Online: 26 July 2018 (15:33:03 CEST)
There are dozens of approved, investigational and experimental antiviral agents. Many of these agents cause serious side effects, which can be revealed only after drug administration. Identification of the side effects prior to drug administration is challenging. Here we describe an ex vivo approach for studying immuno- and neuro-modulatory properties of antiviral agents, which could be associated with potential side effects of these therapeutics. The approach combines drug toxicity/efficacy tests and transcriptomics, which is followed by cytokine and metabolite profiling. We demonstrated the utility of this approach with several examples of antiviral agents. We also showed that the approach can utilize different immune stimuli and cell types. It can also include other omics techniques, such as genomics and epigenomics, to allow identification of individual markers associated with adverse reactions to antivirals with immuno- and neuro-modulatory properties.
REVIEW | doi:10.20944/preprints201909.0212.v1
Subject: Life Sciences, Virology Keywords: positive-sense single-stranded rna viruses; innate immune evasion; type 1 interferon; viral pathogenesis; type 3 interferon
Online: 18 September 2019 (17:12:01 CEST)
Positive-sense single-stranded RNA (+ssRNA) viruses comprise many (re-)emerging human pathogens that pose a public health problem. Our innate immune system and in particular the interferon response form the important first line of defense against these viruses. Given their genetic flexibility, these viruses have therefore developed multiple strategies to evade the innate immune response in order to optimize their replication capacity. Already many molecular mechanisms of innate immune evasion by +ssRNA viruses have been identified. However, research addressing the effect of host innate immune evasion on the pathology caused by the viral infection is less prevalent in literature, though very relevant and interesting. Since interferons have been implicated in inflammatory diseases and immunopathology in addition to their protective role in infection, the influence of antagonizing the immune response may have an ambiguous effect on the clinical outcome of the viral disease. Therefore, this review discusses what is currently known about the role of interferons and host immune evasion in the pathogenesis of emerging viruses belonging to the coronaviruses, alphaviruses and flaviviruses.
ARTICLE | doi:10.20944/preprints202212.0065.v1
Subject: Life Sciences, Genetics Keywords: pulmonary tuberculosis; lymph node tuberculosis; extra-pulmonary tuberculosis; single nucleotide polymorphisms; cytokine; innate immunity; genetic association; genotype; serum
Online: 5 December 2022 (08:00:15 CET)
Background: Tuberculosis (TB) manifests itself primarily in the lungs as pulmonary disease (PTB) and sometimes disseminates to other organs to cause extra-pulmonary TB, such as lymph node TB (LNTB). This study aimed to investigate the role of host genetic polymorphism in immunity related genes to find a genetic basis for such differences. Methods: Sixty-three, Single nucleotide polymorphisms (SNPs) in twenty-three, TB-immunity related genes including eleven innate immunity (SLCA11, VDR, TLR2, TLR4, TLR8, IRGM, P2RX7, LTA4H, SP110, DCSIGN and NOS2A) and twelve cytokine (TNFA, IFNG, IL2, Il12, IL18, IL1B, IL10, IL6, IL4, IL1RA, IL8 and TNFB) genes were investigated to find genetic associations in both PTB and LNTB as compared to healthy community controls. The serum cytokine levels were correlated for association with the genotypes. Results: PTB and LNTB showed differential genetic associations. The genetic variants in the cytokine genes (IFNG, IL12, IL4, TNFB and IL1RA and TLR2,4 associated with PTB susceptibility and cytokine levels but not LNTB (p < 0.05). Similarly, genetic variants in LTA4H, P2RX7, DCSIGN and SP110 showed susceptibility to LNTB and not PTB. Pathway analysis showed abundance of cytokine related variants for PTB and apoptosis related variants for LNTB. Conclusions: PTB and LNTB outcomes of TB infection have a genetic component and should be considered for any future susceptibility and functional studies.
REVIEW | doi:10.20944/preprints202207.0242.v1
Subject: Life Sciences, Immunology Keywords: mouse models; Plasmodium; Adaptive immunity; Innate immunity; T cells; B cells; Macrphages; Neutrophils; Antibodies; Cytokines; parasite control; immunopathogensis
Online: 18 July 2022 (03:12:30 CEST)
Malaria comprises a spectrum of disease syndromes and the immune system is a major participant in malarial disease. This is particularly true in relation to the immune responses elicited against blood stages of Plasmodium-parasites that are responsible for the pathogenesis of infection. Mouse models of malaria are commonly used to dissect the immune mechanisms underlying disease. While no one mouse model of Plasmodium infection completely recapitulates all the features of malaria in humans, collectively the existing models are invaluable for defining the events that lead to the immunopathogenesis of malaria. Here we review the different mouse models of Plasmodium infection that are available, and highlight some of the main contributions these models have made with regards to identifying immune mechanisms of parasite control and the immunopathogenesis of malaria.
ARTICLE | doi:10.20944/preprints202012.0193.v1
Subject: Keywords: Hemocytes; innate immune cells; Phagocytic Activity; Respiratory Burst; microalgae; immunomodulator; shrimps L. vannamei; Vibrio harveyi; Extracellular Polysaccharide (EPS)
Online: 8 December 2020 (09:57:25 CET)
White shrimps are susceptible to outbreaks of vibriosis because they do not have any adaptive immune system, they only have a non-specific innate immune system. The administration of EPS from microalgae Porphyridium cruentum (synonym: P. purpureum) on shrimps Litopenaeus vannamei was investigated to determine the effect of this immunostimulant on their non specific immune response and to test if EPS can be used as a protective agent for shrimp related to Vibrio infection. EPS was given to shrimps by immersion method on day 1 and booster on day 8. Shrimp hemocytes were taken on day 1 (EPS administration), day 7 (no treatment), day 8 (EPS booster) and day 9 (Vibrio infection) and tested for their immune response on each treatment. Result shows an increase in values of all immune parameters in line with the increasing EPS concentration, except the Differential Haemocyte Count (DHC). In detail, an increase was noted in total hemocytes (THC) value, Phagocytotic Activity (PA), Respiratory Burst (RB) in line as the EPS concentration increase. Although there is a decrease after the infection, the value obtained is not lower than the control value. These results indicate that EPS from Porphyrydium enhances immune parameters in shrimp rapidly and has the ability as an immunostimulant or an immunomodulator. It is a good modulator for the non specific immune cells of Pacific white shrimps, and it can be used as a preventive agent against Vibrio.
ARTICLE | doi:10.20944/preprints202207.0426.v1
Subject: Mathematics & Computer Science, Applied Mathematics Keywords: SARS-CoV-2 infection; innate immune response; antigen-specific immune response; kinetic coordination; mathematical model; pathogenesis, long COVID-19
Online: 27 July 2022 (15:11:44 CEST)
A calibrated mathematical model of antiviral immune response to SARS-CoV-2 infection is developed. The model considers the innate and antigen-specific responses to SARS-CoV-2 infection. Recently published data sets from human challenge studies with SARS-CoV-2 were used for parameter estimation. Understanding the regulation of multiple intertwined reaction components of the immune system is necessary for linking the clinical phenotypes of COVID-19 with the kinetics of immune responses. Consideration of multiple immune reaction components in a single calibrated mathematical model allowed us to address some fundamental issues related to pathogenesis of COVID-19, i.e. sensitivity of the peak viral load to parameters characterizing the specific response components, the kinetic coordination of the individual responses, and the factors favoring a prolonged viral persistence. The model provides a tool for predicting the infectivity of patients, i.e. the amount of virus which is transmitted via droplets from the person infected with SARS-CoV-2, depending on the time of infection. The thresholds in the relative unbalance between innate and adaptive response parameters which lead to a prolonged persistence of SARS-CoV-2 due to the loss of a kinetic response synchrony/coordination were identified.
REVIEW | doi:10.20944/preprints202205.0104.v1
Subject: Life Sciences, Virology Keywords: C19ORF66; FLJ11286; shiftless; SVA-1; RyDEN; IRAV; ISG; innate immune response; RNA stabil-ity; translation; RNA granules; ribosomal frameshift
Online: 9 May 2022 (05:57:15 CEST)
Since its initial characterization in 2016, the interferon stimulated gene Shiftless (SHFL) has proven to be a critical piece of the innate immune response to viral infection. SHFL expression stringently restricts the replication of multiple DNA, RNA, and retroviruses with an extraordinary diversity of mechanisms that differ from one virus to the next. These inhibitory strategies include the negative regulation of viral RNA stability, translation, and even the manipulation of RNA granule formation during viral infection. Even more surprisingly, SHFL is the first human protein found to directly inhibit the activity of the -1 programmed ribosomal frameshift, a translation recoding strategy utilized across nearly all domains of life and a several human viruses. Recent literature has shown that SHFL expression also significantly impacts viral pathogenesis in mouse models, highlighting its in-vivo efficacy. To help reconcile the many mechanisms by which SHFL restricts viral replication, we provide here a comprehensive review of this complex ISG, its influence over viral RNA fate, and the implications of its functions on the virus-host arms race for control of the cell.
ARTICLE | doi:10.20944/preprints202102.0422.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Hemocytes; Innate Immune Cells; Phagocytic Activity; Respiratory Burst; White-Shrimp; Microalgae; Immunomodulator; Toxicity; Extracellular Polysaccharide; Vibrio harveyi; Danio rerio
Online: 18 February 2021 (15:56:44 CET)
Exopolysaccharides or extracellular polysaccharides (EPS, sPS) represent valuable metabolite compound synthesized from red microalgae. It is a non toxic natural agent and can be applied as immunostimulant. Toxicity test of exopolysaccharides from Porphyridium has been done in-vivo using zebrafish (Danio rerio) embryonic model, or the ZET (Zebrafish Embryotoxicity Test). The administration of extracellular polysaccharide or exopolysaccharides (EPS) from microalgae Porphyridium cruentum (synonym: P. purpureum) on shrimps Litopenaeus vannamei was investigated to determine the effect of this immunostimulant on their non specific immune response and to test if this compound can be used as a protective agent for shrimp related to Vibrio infection. For immune response, exopolysaccharides was given to shrimps by immersion method on day 1 and booster on day 8. Shrimp hemocytes were taken on day 1 (EPS administration), day 7 (no treatment), day 8 (EPS booster) and day 9 (Vibrio infection) and tested for their immune response on each treatment. Result shows that the EPS is not toxic as represented by the normal embryonic development and the mortality data. In the Pacific whiteshrimps, it show an increase in values of all immune parameters in line with the increasing EPS concentration, except the Differential Haemocyte Count (DHC). In detail, an increase was noted in total hemocytes (THC) value, Phagocytotic Activity (PA), Respiratory Burst (RB) in line with the EPS concentration increase. These results and other previous studies indicate that EPS from Porphyridium is safe and it enhances immune parameters in shrimp rapidly and has the ability as an immunostimulant or an immunomodulator. It is a good modulator for the non-specific immune cells of Pacific white shrimps, and it can be used as a preventive agent against vibriosis.
ARTICLE | doi:10.20944/preprints202206.0023.v1
Subject: Behavioral Sciences, Cognitive & Experimental Psychology Keywords: well-being; innate health; positive psychology; mental health; three principles; self-control; pro-social behaviors; criminology; incarcerated men; prisoners; inmates
Online: 2 June 2022 (02:57:49 CEST)
Knowledge about one’s innate health is central to a variety of positive mental health markers. However, men living in prison rarely receive education about how to access these internal resources. As such, this study seeks to replicate and extend emerging data on an innate health intervention. Volunteers from HMP Nottingham, England (n=126) participated in normal prison programming and the intervention group (n=65) received an additional 3-day intensive. The primary question: Does innate health function as a mediator in the same way self-control does within an incarcerated population? We conducted a mediation analysis, tested social desirability bias, and examined the impact of the intervention on crucial variables. This study found higher levels of innate health, self-control, wellbeing, and prosocial behavior and lower levels of aggression in the intervention group as compared to the control group. Importantly, innate health did play a mediating role equivalent to and/or partnering with self-control.
ARTICLE | doi:10.20944/preprints201609.0080.v1
Subject: Life Sciences, Genetics Keywords: Anatolian Black; East Anatolian Red; South Anatolian Red; Turkish Grey; Holstein Friesian; Innate immunity; Next Generation Sequencing; TLR2; TLR4; TLR6
Online: 23 September 2016 (05:44:43 CEST)
In recent years, the focus of disease resistance and susceptibility studies in cattle have been on determining patterns in the innate immune response of key proteins, such as Toll-like receptors (TLR). In the bovine genome, there are 10 TLR family members and, of these, TLR2, TLR4 and TLR6 are specialized in recognition of bacterial ligands. Indigenous cattle breeds of Anatolia have been reported to show fewer signs of clinical bacterial infections, such as bovine tuberculosis and mastitis, and it is hypothesized that this might be due to a less stringent genetic selection during breeding. In contrast, Holstein-Friesian cattle have been under strong selection for milk production, which may have resulted in greater susceptibility to diseases. To test this hypothesis, we have compared the TLR2, TLR4 and TLR6 genes of Anatolian Black (AB), East Anatolian Red (EAR), South Anatolian Red (SAR), Turkish Grey (TG), and Holstein (HOL) cattle using Next Generation Sequencing. The SAR breed had the most variations overall, followed by EAR, AB, TG and HOL. TG had the most variations for TLR2 whereas SAR had the most variations in TLR4 and TLR6. We compared these variants with those associated with disease and susceptibility traits. We used exon variants to construct haplotypes, investigated shared haplotypes within breeds and determined candidate haplotypes for disease resistance phenotype in Anatolian cattle breeds.
REVIEW | doi:10.20944/preprints201807.0237.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: TRPM7, kinase, inflammation, lymphocytes, calcium signalling, SMAD, TH17, hypersensitivity, regulatory T cells, thrombosis, graft versus host disease, T cells, innate immunity
Online: 13 July 2018 (14:14:56 CEST)
The enzyme-coupled transient receptor potential channel subfamily M member 7, TRPM7, has been associated with immunity and immune cell signalling. Here, we review the role of this remarkable signalling protein in lymphocyte proliferation, differentiation, activation and survival. We also discuss its role in mast cell, neutrophil and macrophage function and highlight the potential of TRPM7 to regulate immune system homeostasis. Further, we shed light on how the cellular signalling cascades involving TRPM7 channel and/or kinase activity culminate in pathologies as diverse as allergic hypersensitivity, arterial thrombosis, and graft versus host disease (GVHD), stressing the need for TRPM7 specific pharmacological modulators.
COMMUNICATION | doi:10.20944/preprints202010.0262.v1
Subject: Medicine & Pharmacology, Allergology Keywords: cytomegalovirus (CMV); definitions of cytomegalovirus disease; logarithmic phase infection; innate immune response; CD14; monocytes; nonclassical monocytes; HLA-DR; adaptive immune response; interferon; monocytosis
Online: 13 October 2020 (08:52:11 CEST)
It has recently been discovered that mere cell contact by human cytomegalovirus (CMV) particles leads to profound modulation of cellular gene expression. Reduced monocyte human leukocyte antigen (HLA-DR) expression is a novel biomarker of severity and outcome in many diseases. Modulation of CD14 protein by CMV was shown in vitro, but little is known about the phenomenon in vivo (during active cytomegalovirus disease). Therefore, we investigated monocyte CD14 and HLA-DR expression in CMV infected patients in relation to logarithmic phase of infectious process. Samples from patients with active CMV replication (exponential growth of CMV viremia) were tested. After CD45/SSC gating monocyte CD14 and HLA-DR expression were determined by double-color flow-cytometry. Significant monocytosis and poor correlation between CMV replication and CD14+HLA-DR(-) cells prompted CD14 investigation. During logarithmic phase of CMV infection increased count and percentage of CD14low monocytes were observed which correlated with viral replication in several clinical situations except when there was a rapid recovery without relapse. Furthermore, most of CD14low monocytes are HLA-DR+. The increase of CD14low monocytes is also observed under the influence of high dose of glucocorticoids (20 mg of dexamethasone). The reduction in CD14 induced by CMV and dexamethasone indicates that the monocyte balance is disturbed between the classical and non-classical phenotype. A high percentage of CD14lowHLA-DR+ probably gives rise to adaptive and a decrease of innate immune response. In light of the logarithmic increase of viral load (with exponent between 3,23 and 5,77), high monocytosis above 1200 / µl is a hallmark of CMV replication.
REVIEW | doi:10.20944/preprints202007.0712.v1
Subject: Life Sciences, Virology Keywords: Group-B Enterovirus; RNA domain-I; viral ribonucleoprotein complexes; Enterovirus replication; 5’ terminally deleted viral forms; antiviral innate immune response; type I Interferon
Online: 30 July 2020 (10:00:13 CEST)
Group-B enteroviruses (EV-B) are ubiquitous naked single-stranded positive RNA viral pathogens that are responsible for common acute or persistent human infections. Their genome is composed in the 5'end by a non-coding region, which is crucial for the initiation of the viral replication and translation processes. RNA domain-I secondary structures can interact with viral or cellular proteins to form viral ribonucleoprotein (RNP) complexes regulating viral genomic replication, whereas RNA domains-II to -VII (IRES) are known to interact with cellular ribosomal subunits to initiate the viral translation process. Natural 5’ terminally deleted viral forms lacking some genomic RNA domain-I secondary structures have been described in EV-B induced murine or human infections. Recent in vitro studies have evidenced that the loss of some viral RNP complexes in the RNA domain-I can modulate the viral replication and infectivity levels in EV-B infections. Moreover, the disruption of secondary structures of RNA domain-I could impair viral RNA sensing by RIG-I or MDA5 receptors, a way to overcome antiviral innate immune response. Overall, natural 5′ terminally deleted viral genomes resulting in the loss of various structures in the RNA domain-I could be major key players of host-cell interactions driving the development of acute or persistent EV-B infections.