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.
REVIEW | doi:10.20944/preprints202311.1946.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: HCV; Innate immunity; Adaptive immunity
Online: 30 November 2023 (10:41:51 CET)
Hepatitis C virus (HCV) is diffused worldwide, and it is responsible for potentially severe chronic liver disease and primary liver cancer. Chronic infection remains for life if not spontaneously eliminated and viral persistence profoundly impairs the efficiency of host’s immunity. Attempts have been made to develop an effective vaccine, but efficacy trials have met with failure. The availability of highly efficacious direct acting antivirals (DAA) has shed hopes for progressive elimination of chronic HCV infection; however, this approach requires a global monumental effort. Moreover, DAA treatment does not completely restore the normal immunologic homeostasis. Here we discuss the main immunological features of immune responses to HCV and the epigenetic scars that chronic viral persistence leaves behind.
ARTICLE | doi:10.20944/preprints202308.0670.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: zebrafish; BMP4; antiviral innate immunity; IFN; p38 MAPK pathway
Online: 8 August 2023 (11:39:28 CEST)
Bone Morphogenetic Proteins (BMPs) are a group of structurally and functionally related signaling molecules that comprise a subfamily, belonging to the TGF-β superfamily. Most BMPs play roles in the regulation of embryonic development, stem cell differentiation, tumor growth and some cardiovascular and cerebrovascular diseases. Although evidences are emerging for the antiviral immunity of a few BMPs, more BMPs are needed to determine whether this function is universal. Here we identified the zebrafish bmp4 ortholog, whose expression is up-regulated by challenge with virus or its mimic poly(I:C). Overexpression of bmp4 in EPC cells significantly decreased the viral titer of GCRV-infected cells. Moreover, compared to wild type zebrafish, viral load and mortality were significantly increased in both larvae and adults of bmp4-/- mutant zebrafish infected with GCRV virus. We further demonstrated that Bmp4 promotes the phosphorylation of Tbk1 and Irf3 through p38 MAPK pathway, thereby inducing the production of type I IFNs in response to virus infection. These data suggest that Bmp4 runs an important role in the host defense against virus infection. Our study expands the understanding of BMP protein functions and opens up new targets for the control of viral infection.
HYPOTHESIS | doi:10.20944/preprints202006.0178.v1
Subject: Biology And Life Sciences, Anatomy And 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: Biology And Life Sciences, Biochemistry And Molecular Biology 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: Biology And Life Sciences, Immunology And Microbiology 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.
BRIEF REPORT | doi:10.20944/preprints202306.0112.v1
Subject: Medicine And Pharmacology, Epidemiology And Infectious Diseases Keywords: immunity; obesity; insulin resistance; innate and adaptive; treg; glutathione; cytokine storm
Online: 2 June 2023 (02:11:22 CEST)
The risks for complications of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection are higher in obese individuals. Obesity is a state of chronic low-grade inflammation, with high leptin levels due to leptin resistance, high basal levels of other pro-inflammatory cytokines such as TNF-alpha, MCP-I and IL-6, and low adiponectin levels, thus contributing to a state of defective innate immunity as well as impaired B and T cell responses. Obesity is a risk factor for metabolic syndrome, diabetes, cardiovascular disease and hypertension. It has been observed that pre-existence of these diseases confers a higher risk of severe SARS CoV2 infection as well as the need for intensive care; even below the age of 60 years if their body mass index (BMI) is greater than 30 kg/m2, and even more so if it is > 35 kg/m2. The metabolic factors contributing to the changes in altering the immune mechanisms in obese individuals and how this enhances the susceptibility to infection and development of serious SARS-CoV2 infection have been the subject of many debates. Future development of targeted therapy and guidelines will be benefited by greater understanding into these metabolic pathways.
REVIEW | doi:10.20944/preprints202209.0487.v2
Subject: Medicine And Pharmacology, Cardiac And Cardiovascular Systems 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.
REVIEW | doi:10.20944/preprints202310.0678.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: adaptive immunity to COVID-19; clinical vaccine trials; COVID-19; COVID-19 vaccines; innate immunity to COVID-19; mucosal vaccines; nasal vaccines; SARS-CoV-2; upper respiratory tract immunity; vaccine safety
Online: 11 October 2023 (10:52:38 CEST)
Rapid development and deployment of vaccines greatly reduced mortality and morbidity during the COVID-19 pandemic. The most widely used COVID-19 vaccines approved by national regulatory authorities require intramuscular administration. SARS-CoV-2 initially infects the upper respiratory tract where the infection can be eliminated with little or no symptoms by an effective immune response. Failure to eliminate SARS-CoV-2 in the upper respiratory tract results in lower respiratory tract infections that can lead to severe disease and death. Presently used intramuscularly administered COVID-19 vaccines are effective in reducing severe disease and mortality but are not entirely able to prevent asymptomatic and mild infections as well as person to person transmission of the virus. Individual and population differences also influence susceptibility to infection and the propensity to develop severe disease. This article provides a perspective on the nature and the mode of delivery COVID-19 vaccines that can optimize protective immunity in the upper respiratory tract to reduce infections and virus transmission as well as severe disease.
REVIEW | doi:10.20944/preprints202212.0418.v2
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: COVID-19; B Cells; Neutrophils; T Cells; NK Cells; Innate; Adaptive; Cytokines; Chemokines; Adhesion Molecules; Antibody; Cluster of Differentiation; Receptors; Proteins; SARS-CoV-2; Serology
Online: 27 December 2022 (03:19:48 CET)
The coronavirus 2019 (COVID-19) pandemic was caused by a positive sense single-stranded RNA (ssRNA) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, other human coronaviruses (hCoVs) exist, of which Middle East Respiratory Syndrome (MERS) and SARS-CoV (SARS) showed higher mortality rates without causing a pandemic. As of December 2022, SARS-CoV-2 has resulted in over 6.6 million deaths worldwide through an array of acute to chronic pathologies. Historical pandemics include smallpox and influenza with efficacious therapeutics utilized to reduce overall disease burden. Therefore, immune system process analysis is required to compare innate and adaptive immune system interactions. Lymphatic system organs include bone marrow and thymus using a network of nodes throughout which white blood cells traverse glycolipid membranes utilizing cytokines and chemokine gradients that affect cell development, differentiation, proliferation, and migration processes as well as genetic factors affecting cell receptor expression. Innate processes involve antigen-presenting cells and B lymphocyte cellular responses to pathogens relevant to other viral and bacterial infections but also in oncogenic diseases. Such processes utilize cluster of differentiation (CD) marker expression, major histocompatibility complexes (MHC), pleiotropic interleukins (IL) and chemokines. The adaptive immune system consists of Natural Killer (NK) and T cells. Other viruses are also contributory to cancer including human papillomavirus (cervical carcinoma ), Epstein-Barr virus (EBV) ( lymphoma), hepatitis B and C (hepatocellular carcinoma) and human T cell leukemia virus-1 (adult T-cell leukemia). Bacterial infections also increase the risk of developing cancer( e.g. H. pylori). Therefore, as the above factors can cause both morbidity and mortality along-side being transmitted within clinical and community settings, it is appropriate to now examine advances in single cell sequencing, FACS analysis and many other laboratory techniques that allow insights into discoveries of newer cell types. These developments offer improved clarity and understanding that over-lap with known autoimmune conditions that could be affected by innate B cell or T cell responses to SARS-CoV-2 infection. Thus, this review quantifies and outlines the nature of specific receptors and proteins relevant to clinical laboratories and medical research by documenting both innate and adaptive immune system cells within current coronavirus immunology case study data and other pathologies to date.
ARTICLE | doi:10.20944/preprints201906.0028.v1
Subject: Biology And Life Sciences, Immunology And Microbiology 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.
REVIEW | doi:10.20944/preprints202305.1582.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: NETs; innate immunity; mycobacteria.
Online: 23 May 2023 (05:30:13 CEST)
Mycobacterium tuberculosis complex causes tuberculosis (TB), a disease that causes pulmonary inflammation but can also affect other tissues. Despite macrophages having a defined role in TB immunopathogenesis, other innate immune cells, such as neutrophils, are involved in this process. These cells have high phagocytic ability and a microbial-killing machine comprised of enzymes, antimicrobial peptides, and reactive oxygen species. In the last two decades, a new neutrophil immune response, the neutrophil extracellular traps (NETs), has been intensely researched. NETs comprise DNA associated with histones, enzymes, and antimicrobial peptides. These structures are related to antimicrobial immune response and some immuno-pathogenesis mechanisms. This mini review highlights the role of NETs in tuberculosis and how they can be helpful as a diagnostic tool and/or therapeutic target.
REVIEW | doi:10.20944/preprints202308.0706.v2
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Interferon; Innate; Adaptive; Genetic; Molecular
Online: 26 September 2023 (11:35:53 CEST)
Interferons were the original prototype cytokine system discovered in 20th-century research. As the name implies, they were originally thought to be synthesised and secreted between cells. Thanks to technological advances, the processes involved in protein secretion can be explained comparatively more clearly at both the genetic and biochemical levels. The discovery of interferon (IFN) occurred when genetic research was still in its infancy. Franklin and Wilkins discovered the structure and function of deoxyribonucleic acid (DNA) at the same time as Crick and Watson; however, Isaacs and Lindemann, two scientists, described the first IFN in 1957. Mutations can be caused by inherent genetic protein synthesis and during infection as well as within IFN regulation pathways affecting cell proliferation. This remains central to host cell IFN synthesis and effects through IFN protein receptor subunits defined by 6 protein domains. Type II IFN is key to immune cell function secreted by a variety of immune cells, mainly natural killer (NK) as well as T cells. Single–stranded and/or double–stranded RNA/DNA viruses, as well as bacterial infections (e.g., Escherichia coli) and fungal infections (e.g., Aspergillus), also affect IFN regulation. Pathogenic proteins utilise intra/extracellular proteins that sense foreign antigens like Toll–like Receptors (TLRs), affected by mutations within the human cellular IFN transduction pathways. Since the discovery of the third IFN type in 2003, when immune cell phenotypes were further characterised, questions remain about the immunological mechanisms contributing to the regulation of the innate and adaptive host immune system. Alterations in the synthesis of type I/II/III host IFNs can differentially and beneficially alter homeostatic cellular pathways in pathological disease, with type I IFN being synthesised in cancer as well as by homeostatic cells. Therefore, considered here are the overall IFN molecular, cell regulatory mechanisms in the context of immune cell research developments.
REVIEW | doi:10.20944/preprints202307.0695.v2
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Adaptive; Ebola; Filoviridae; Immunology; Innate; Molecular
Online: 12 September 2023 (02:40:32 CEST)
Ebola virus is a zoonotic virus comprised of 6 different species designated within the family Filoviridae and genus Ebolavirus. The first recorded outbreak of an Ebola virus (EBOV) was in Yambuku, Zaire (ZEBOV) in 1976, followed by Sudan Ebola virus (SUBOV) later that year. Outbreaks have been increasing throughout the 21st century, and mortality rates can reach up to 90%. Such extraordinary virulence is evidenced with few pathogens, similarly with Marburg virus (MARV) that originated in Uganda and was first detected in Germany in 1967. The virulent nature of filovirus disease has established these related viruses as a formidable global concern. There are currently four types of Ebolaviridae species known to infect humans, with two more recently identified in other animals that are genomically different with respect to cellular pathogenesis or aetiology of disease. Recent advances into understanding the pathogenesis of filovirus disease infections have been remarkable, yet the immunological response to filovirus infection remains unknown. Scientific analysis of cellular mechanisms can provide insight into virulence factors utilised by other pathogenic viruses that also cause febrile illness with occasional haemorrhagic fever in humans. In this review, we aim to provide a brief summary of EBOV proteins and the role of innate and adaptive immune cells known since 2000. We will consider the relevance and implications of immunological proteins measured by CD marker, alongside cytokine, chemokine and other biologically relevant pathways, as well as genetic research. Thorough understanding of immunological correlates affecting host responses to Ebola viruses will facilitate both clinical and applied research knowledge, contributing towards protection against potential public health threats.
ARTICLE | doi:10.20944/preprints202112.0009.v1
Subject: Medicine And Pharmacology, Immunology And Allergy 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 And Pharmacology, Gastroenterology And Hepatology 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/preprints202309.0797.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: atherosclerosis; innate immunity; signaling pathways; trained immunity
Online: 13 September 2023 (07:54:33 CEST)
Innate immune pathways play a crucial role in the development of atherosclerosis, from sensing initial danger signals to the long-term reprogramming of immune cells. Despite the success of lipid-lowering therapy, anti-hypertensive medications, and other measures in reducing complications associated with atherosclerosis, cardiovascular disease (CVD) remains the leading cause of death worldwide. Consequently, there is an urgent need to devise innovative preventive and therapeutic strategies to alleviate the global burden of CVD. Extensive experimental research and epidemiological studies have demonstrated the dominant role of innate immune mechanisms in the progression of atherosclerosis. Recently, landmark trials including CANTOS, COLCOT, and LoDoCo2 have provided solid evidence, demonstrating that targeting innate immune pathways can effectively reduce the risk of CVD. These groundbreaking trials mark a significant paradigm shift in the field and open new avenues for atheroprotective treatments. It is therefore crucial to comprehend the intricate interplay between innate immune pathways and atherosclerosis for the development of targeted therapeutic interventions. Additionally, unraveling the mechanisms underlying the long-term reprogramming may offer novel strategies to reverse the pro-inflammatory phenotype of immune cells and restore immune homeostasis in atherosclerosis. In this Review, we present an overview of the innate immune pathways implicated in atherosclerosis, with a specific focus on the signaling pathways driving chronic inflammation in atherosclerosis and the long-term reprogramming of immune cells within the atherosclerotic plaque. Elucidating the molecular mechanisms governing these processes presents exciting opportunities for the development of a new class of immunotherapeutic approaches aimed at reducing inflammation and promoting plaque stability. By addressing these aspects, we can potentially revolutionize the management of atherosclerosis and its associated cardiovascular complications.
ARTICLE | doi:10.20944/preprints202306.1894.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: OTUD6A; IFNβ; Ubc13; NF-κB; innate immunity
Online: 27 June 2023 (11:42:11 CEST)
Abstract: OTUD6A is a deubiquitinase that plays crucial roles in various human diseases. However, the precise regulatory mechanism of OTUD6A remains unclear. In this study, we found that OTUD6A significantly inhibited the production of type I interferon. Consistently, peritoneal macrophages and bone marrow-derived macrophages from Otud6a-/- mice produced more type I interferon after virus infection compared to cells from WT mice. Otud6a-/- mice also exhibited increased resistance to lethal HSV-1 and VSV infections, as well as LPS attack due to decreased inflammatory responses. Mechanistically, mass spectrometry results revealed that UBC13 was an OTUD6A-interacting protein, and the interaction significantly enhanced after HSV-1 stimulation. Taken together, our findings suggest that OTUD6A plays a crucial role in the innate immune response and may serve as a potential therapeutic target for infectious disease.
REVIEW | doi:10.20944/preprints202309.0786.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: herpesvirus; ADAR; RNA editing; miRNA; latency; innate immunity
Online: 13 September 2023 (02:43:06 CEST)
A single paragraph of about 200 words maximum. For research articles, abstracts should give a pertinent overview of the work. We strongly encourage authors to use the following style of structured abstracts, but without headings: (1) Background: Place the question addressed in a broad context and highlight the purpose of the study; (2) Methods: briefly describe the main methods or treatments applied; (3) Results: summarize the article’s main findings; (4) Conclusions: indicate the main conclusions or interpretations. The abstract should be an objective representation of the article and it must not contain results that are not presented and substantiated in the main text and should not exaggerate the main conclusions.
REVIEW | doi:10.20944/preprints202305.0760.v2
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Nanoparticles; virus; bacteria; protein corona; glucocorticoid; innate immunity
Online: 16 June 2023 (10:38:50 CEST)
We advance the notion that much, like artificial nanoparticles, relatively more complex biological entities with nanometric dimensions such as pathogens (viruses, bacteria and other microorganisms) may also acquire a biomolecular corona, upon entering the blood circulation of an organism. We view this biomolecular corona as a component of a much broader non-cellular blood interactome that can be highly specific to the organism, akin to components of the innate immune response to an invading pathogen. We review published supporting data and generalize these notions from artificial nanoparticles to viruses and bacteria. Characterization of the non-cellular blood interactome of an organism may help explain apparent differences in the susceptibility to pathogens among individuals. The non-cellular blood interactome is a candidate therapeutic target to treat infectious and non-infectious conditions.
REVIEW | doi:10.20944/preprints202105.0625.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Toll-Like Receptor; Innate Immunity; Inflammation; Anti-inflammation
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/preprints202307.0673.v2
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Orthopoxvirus; Molecular; Health; Immunology; Monkeypox; Smallpox; Innate; Adaptive; Cells
Online: 12 September 2023 (02:45:52 CEST)
Since 2019, notable global viral outbreaks have occurred necessitating further research and healthcare system investigations. Following the COVID—19 pandemic, an unexpected duality has occurred of SARS–CoV–2 and monkeypox virus (MPXV) infections. Monkeypox virus is of the Orthopoxviridae genus, belonging to the family Poxviridae. Zoonotic transmission (animal to human transmission) may occur. The Orthopoxviridae genus includes other Orthopoxviruses (OPXV) present in animal host reservoirs that include cowpox viruses (CPXV), vaccinia virus (VACV) and variola virus (VARV), with the latter being causal agent of smallpox and excessive mortality. The aim in this review is to present facts about MPXV specific pathogenesis, epidemiology, and immunology alongside historical perspectives. Monkeypox virus was rarely reported outside Africa before April 2000. Early research since 1796 contributed towards eradication of VARV leading to immunisation strategies. The World Health Organisation (WHO) announcement that VARV had been eradicated was confirmed in 1980. On the 23rd of July 2022, the WHO announced MPXV as a health emergency. Therefore, concern due to propagation of MPXV causing MPOX disease requires clarity. Infected hosts display symptoms like extensive cellular initiated rashes and lesions. Infection with MPXV makes it difficult to differentiate from other diseases or skin conditions. Anti–viral therapeutic drugs were typically prescribed for smallpox and MPOX disease; however, the molecular and immunological mechanisms with cellular changes remain of interest. Furthermore, no official authorised treatment exists for MPOX disease. Some humans across the globe may be considered at risk. Historically, presenting symptoms of MPOX resemble other viral diseases. Symptoms include rashes or lesions like Streptococcus, but also human herpes viruses (HHV) including Varicella zoster (VZV).
REVIEW | doi:10.20944/preprints202305.2248.v1
Subject: Medicine And Pharmacology, Veterinary Medicine Keywords: Keywords: Osteoarthritis, Neutrophil, Innate Immunity, Neutrophil Extracellular Traps (NET).
Online: 31 May 2023 (12:55:03 CEST)
Osteoarthritis (OA) is the most common degenerative joint disease that causes chronic pain and disability. Different innate immune components, including macrophages, T cells, and neutrophils, participate in osteoarthritis pathophysiology. Neutrophils are the most abundant circulating leukocytes with multiple specialized functions contributing to innate and adaptive immune functions. Although neutrophils produce proinflammatory cytokines and chemokines, reactive oxygen species (ROS), matrix-degrading enzymes, and neutrophil extracellular traps (NET) that promote joint degradation as the first recruit cells in an inflamed joint, these cells also play an important role in joint repair by regulating the immune response, releasing anti-inflammatory factors, and activating some protective genes. In this review, various aspects of neutrophil biology, their role in inflammation and its association with osteoarthritis, and possible therapeutic approaches to target neutrophils for the treatment of osteoarthritis are described. Understanding neutrophil heterogeneity and their mechanisms of action in joint inflammation, provides a potential strategy for OA management.
REVIEW | doi:10.20944/preprints202011.0477.v1
Subject: Medicine And Pharmacology, Immunology And Allergy 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 And Pharmacology, Pathology And 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 And Pharmacology, Pathology And 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 And Life Sciences, 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: Biology And Life Sciences, Immunology And Microbiology 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.
ARTICLE | doi:10.20944/preprints202310.1566.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: innate immunity; inflammasome; cardiac transplantation; rejection; allograft coronary artery disease
Online: 25 October 2023 (08:11:34 CEST)
Background Recent studies indicate that donor innate immune responses participate in initiating and accelerating innate responses and allorecognition in the recipient. These immune responses negatively affect recipient outcomes and predispose recipients to allograft coronary artery vasculopathy (CAV). We hypothesized that donor cause of death (COD) associated with higher levels of innate immune response would predispose recipients to more adverse outcomes post-transplant, including CAV. Methods We performed a single-institution retrospective analysis comparing donor characteristics and COD to recipient adverse cardiovascular outcomes. We analyzed the medical records of local adult donors (age 18-64) in a database of donors where adequate data was available. We linked donor characteristics and COD to recipient adverse cardiac outcomes after transplant, including cardiovascular (CV) death and incidence of significant antibody-mediated rejection (pAMR) after transplant (>2 episodes of pAMR within 90 days post-transplant). The data were analyzed using logistic regression, log-rank test of differences, and Tukey Contrast. Results Donor advanced age, female sex, and CODs of motor vehicle accident and intracranial hemorrhage were significantly associated with a higher incidence of recipient CV death and early pAMR compared to other donor characteristics and CODs. Conclusions In this single institution study, we found that recipients with hearts from donors over 40 years, donors who were female, or donors who died with a COD of motor vehicle accidents or intracranial hemorrhage had a higher frequency of CV related deaths and early pAMR. Donor monitoring and potential treatment of innate immune activation may decrease subsequent recipient innate responses and allorecognition stimulated by donor derived inflammatory signaling which lead to adverse outcomes.
REVIEW | doi:10.20944/preprints202306.0715.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: lectin; carbohydrate; marine animal; toxin; pore-forming protein; innate immunity
Online: 9 June 2023 (12:12:43 CEST)
Glycans play important roles as recognition molecules on cell surfaces in living organisms due to their remarkable structural diversity. Carbohydrates exist in numerous isomeric forms and can adopt diverse structures through various branching patterns. Despite their relatively small molecular weights, they exhibit extensive structural diversity. On the other hand, lectins, also known as carbohydrate-binding proteins, not only recognize and bind to the diverse structures of glycans but also induce various biological reactions based on structural differences. Initially discovered as hemagglutinins in plant seeds, lectins have been found to play significant roles in cell recognition processes in higher vertebrates. However, our understanding of lectins in marine animals, particularly marine invertebrates, remains limited. Recent studies have revealed that marine animals possess novel lectins with unique structures and glycan recognition mechanisms not observed in known lectins. Of particular interest is their role as pattern recognition receptors in the innate immune system, where they recognize glycan structures of pathogens. Furthermore, lectins serve as toxins for self-defense against foreign enemies. Recent discoveries have identified various pore-forming proteins containing lectin domains in fish venoms and skins. These proteins utilize lectin domains to bind target cells, triggering oligomerization and pore formation in the cell membrane. These findings have spurred research into the new functions of lectins and lectin domains. In this review, we present recent findings on the diverse structures and functions of lectins in marine animals.
COMMUNICATION | doi:10.20944/preprints202304.0111.v2
Subject: Medicine And Pharmacology, Transplantation Keywords: Xenotransplantation; chemorepulsion; adaptive immunity; innate immunity; dysregulated coagulation; complement cascade
Online: 10 April 2023 (09:14:25 CEST)
Recently, two pig-to-human kidney transplants and a pig-to-human heart transplant were completed. The kidney trials involved a patient who was deceased and a patient who was brain dead. They seemed to indicate that pig kidneys can be at least somewhat functional in humans. However, patients still have to be under severe immunosuppression - and the first patient to receive a porcine heart passed away after two months. It is difficult to know exactly which proteins we need to overexpress or underexpress/knockout in a porcine organ to negate the human recipient’s immunological response to it. And testing different porcine organ genetic modifications in baboons can cost around $500,000 per transplant. But there might be a way to decrease immunogenicity where we don’t have to worry so much about modifying the animal’s organs genetically. First, however, we would have to prevent complement factor-mediated lysis of the porcine vascular endothelial cells, which we have made much progress on with triple knockout animals. Then, we could modify the porcine organ so that the cells of said organ secrete a small molecule or peptide that acts as a chemorepellent for the host immune cells. The host immune cells can be modified via bone marrow transplant or vector delivery to express the chemorepulsion receptor.
REVIEW | doi:10.20944/preprints202104.0036.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology 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 And Life Sciences, Anatomy And Physiology 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: Biology And Life Sciences, Immunology And Microbiology 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: Biology And Life Sciences, Immunology And Microbiology 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/preprints202310.0733.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: liver; intestine-liver axis; innate immune genes; comparative genomics; IL-2
Online: 12 October 2023 (02:30:26 CEST)
The liver is not only a digestive gland, but also an immune tissue that receives a double infusion from the hepatic artery and the hepatic portal vein. Receiving 80% of its blood supply from the intestine through the hepatic portal vein system, the liver is enriched with a large number of innate immune cells, which carry out the process of immune response by detecting pathogens entering the organism through the intestine. The intestine and liver communicate extensively through the bile ducts, portal vein and the somatic circulation, a bidirectional communication known as the intestinal-liver axis. The mammalian gut is considered an important microbial ecosystem. The interplay between the natural immune system and microbes coordinates the physiology of the whole organism, and in specific mammalian lineages, there is a dependency between the host and its associated microbes. To this end, we explored the regulatory mechanisms of natural immunity genes at the genome-wide level. Based on comparative genomics, 1473 bovine natural immunity genes were obtained by collecting the latest reports of human natural immunity genes and updated bovine genomic data for comparison, and a bovine natural immunity gene database was initially constructed to screen and match calf liver natural immunity differential genes mainly affected by the phylum Mimosoidea and the phylum Thick-walled Bacteria, and 16 differentially expressed natural immunity genes were obtained. In addition, the results of IPA analysis indicated that the upstream factor IL-2 initiated the PI3K/AKt/mTOR, mitogen-activated protein kinase (MAPK) pathway and JAK/STAT5 pathway, leading to the liver's involvement in gut microbial immune regulation.
ARTICLE | doi:10.20944/preprints202309.1132.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Covid-19; innate immune memory; rheumatoid arthritis; autoimmune disease; redox bioregulation
Online: 18 September 2023 (08:53:40 CEST)
The best form of prevention against human infection through bacteria, viruses and other parasites is ozone disinfection of wastewater and drinking water as a highly effective, well-known method. As a therapeutic measure, various preclinical studies showed promising results, which are being revisited and reconsidered in times of pandemics and led to interesting results in recent clinical trials and reports, as presented by the example of protective measures against covid-19 in particularly vulnerable clinical personnel. In patients with rheumatoid arthritis, repeated ozone treatments have led to new findings in the "immunomodulation" through ozone. The more effective immune response is discussed as the response of innate immune memory and opens interesting aspects for complementary treatment of autoimmune diseases.
BRIEF REPORT | doi:10.20944/preprints202305.1794.v1
Subject: Medicine And Pharmacology, Medicine And Pharmacology Keywords: oligonucleotide vaccines; SARS-CoV-2; phosphorothioate oligonucleotides; innate immunity; adaptive immunity
Online: 25 May 2023 (10:13:35 CEST)
The main problem in creating anti-coronavirus vaccines that target mainly proteins of the outer membrane of the virus remains the rapid variability of the RNA genome of the pathogen that encodes these proteins. In addition, the introduction of technologies that can provide affordable and fast production of flexible vaccine formulas that easily adapt to the emergence of new subtypes of SARS-CoV-2 is required. Universal oligonucleotide vaccine can take into account the dynamics of rapid changes in the virus genome, as well as be synthesized on automatic DNA synthesizers in large quantities in a short time. In this brief report, the effectiveness of four phosphorothioate constructs of the La-S-so type oligonucleotide vaccine will be evaluated for the first time on transgenic mice [B6.Cg-Tg (K18-ACE2)2]. In our primary trials, the oligonucleotide vaccine increased the survival rate of animals infected with SARS-CoV-2 and also reduced the destructive effects of the virus on the lung tissue of mice. The obtained results show the perspective of the development of vaccine constructs of the La-S-so type for the prevention of coronavirus infections, including those caused by SARS-СoV-2.
REVIEW | doi:10.20944/preprints202305.1680.v1
Subject: Medicine And Pharmacology, Clinical Medicine Keywords: Chronic kidney disease; Pentraxin-3; Renal Replacement Therapies; Inflammaging.; innate immunity
Online: 24 May 2023 (03:59:18 CEST)
Chronic kidney disease (CKD) is actually considered a public health priority according to the increasing number of patients affected by this condition: this casuistry is not only related to specific glomerular, tubular or autoimmune diseases or a consequence of acute kidney injury (AKI) episodes leading to organ failure, but it is tied to the progression of life expectancy and the impact of comorbidities such as cardiovascular disease, diabetes and cancer. CKD and its comorbidities promote low grade inflammatory status with an impact on patients’ clinical conditions, reducing their possibility for kidney transplantation or graft survival and their survival when receiving renal replacement therapies such as hemodialysis (HD) or peritoneal dialysis (PD). CKD is often referred to as an ageing accelerator: innate immune system dysregulation, in the uraemic proinflammatory milieu, is involved in this accelerated senescence phenomena and pentraxins, particularly Pentraxin-3 (PTX-3), are of particular interest in the development of kidney disease. A complete understanding of the mechanism of CKD progression, innate immune system involvement and a proper definition of PTX-3 role in kidney disease, could redefine the approach for diagnosis and a more centered patients’ management to slow down CKD progression over time and reduce its clinical and social impact.
ARTICLE | doi:10.20944/preprints202108.0494.v1
Subject: Biology And Life Sciences, Immunology And Microbiology 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: Biology And Life Sciences, Biochemistry And Molecular Biology 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
Subject: Medicine And Pharmacology, Epidemiology And Infectious Diseases Keywords: Sex; COVID-19; SARS Cov-2; ACE2; innate immunity; adaptive immunity
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/preprints202308.0635.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: COVID‐19; IL18; TLR2; TLR4; CD14; CD40; CARD8; innate immunity; polymorphism; prognosis
Online: 8 August 2023 (11:53:03 CEST)
COVID-19 is characterized by a heterogeneous clinical presentation and prognosis. Risk factors contributing to the development of severe disease include old age and the presence of comorbidities. However, the genetic background of the host has also been recognized as an important determinant of disease prognosis. Considering the pivotal role of innate immunity in the control of SARS-CoV-2 infection, we analyzed the possible contribution of several innate immune gene polymorphisms (including TLR2-rs5743708, TLR4-rs4986790, TLR4-rs4986791, CD14-rs2569190, CARD8-rs1834481, IL18-rs2043211 and CD40-rs1883832) in disease severity and prognosis. A total of 249 individuals were enrolled and further divided into five (5) groups, according to the clinical progression scale provided by the World Health Organization (WHO) (asymptomatic, mild, moderate, severe and critical). We identified that elderly patients with obesity and/or diabetes mellitus were more susceptible to developing pneumonia and respiratory distress syndrome after SARS-CoV-2 infection, while the IL18-rs1834481 polymorphism was an independent risk factor for developing pneumonia. Moreover, individuals carrying either the TLR2-rs5743708 or the TLR4-rs4986791 polymorphisms exhibited a 3.6- and 2.5-fold increased probability for developing pneumonia and a more severe disease, respectively. Our data supports the notion that the host’s genetic background can significantly affect COVID-19 clinical phenotype, also suggesting that the IL18-rs1834481, TLR2-rs5743708 and TLR4-rs4986791 polymorphisms may be used as molecular predictors of COVID-19 clinical phenotype.
ARTICLE | doi:10.20944/preprints202307.0420.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: PEDV; porcine innate immunity; pattern recognition receptor (PRR); signaling adaptors; knockout; siRNA
Online: 6 July 2023 (11:50:52 CEST)
Porcine epidemic diarrhea virus (PEDV) has caused great damage to the global pig industry. The innate immunity plays a significant role in resisting viral infection, however, the exact role of innate immunity in the anti-PEDV response has not been fully elucidated. In this study, we observed that various porcine innate immune signaling adaptors are involved in the anti-PEDV activity. Among these, TRIF and MAVS showed the strongest anti-PEDV activity. The endogenous TRIF, MAVS and STING were selected for further examination of anti-PEDV activity. Agonist stimulation experiments showed that TRIF, MAVS and STING signaling all have obvious anti-PEDV activity. The siRNA knockdown assay showed that TRIF, MAVS and STING are also all involved in anti-PEDV response, and their remarkable effects on PEDV replication were confirmed in TRIF-/-, MAVS-/- and STING-/- Vero cells. For further verification, the anti-PEDV activity of TRIF, MAVS and STING could be reproduced in porcine IPEC-DQ cells. In summary, this study reveals that multiple pattern recognition receptor (PRR) signaling pathways of porcine innate immunity play an important role in the anti-PEDV infection, providing new and useful antiviral knowledge for prevention and control of PEDV spreading.
ARTICLE | doi:10.20944/preprints202306.1827.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Influenza; NK cells; RIG-I; IFN-a/b; innate nucleic acid receptors
Online: 26 June 2023 (14:41:45 CEST)
Immune surveillance by natural killer (NK) cells and their recruitment to sites of inflammation renders them susceptible to viral infection, potentially modulating their effector function. Here, we analyzed innate RNA receptor signaling in NK cells downstream of direct Influenza A virus (IAV) infection and its impact on NK cell effector function. Infection of NK cells with IAV resulted in the activation of TBK1, NF-κB and subsequent type-I IFN secretion. CRISPR- generated knockouts in primary human NK cells revealed that this effect depended on the antiviral cytosolic RNA receptor RIG-I. Transfection of NK cells with synthetic 3p-dsRNA, a strong RIG-I agonist that mimics viral RNA, resulted in a similar phenotype and rendered NK cells resistant to subsequent IAV infection. Strikingly, both IAV infection and 3p-dsRNA transfection enhanced degranulation and cytokine production by NK cells when exposed to target cells. Thus, RIG-I activation in NK cells both supports their cell intrinsic viral defense and enhances their cytotoxic effector function against target cells.
ARTICLE | doi:10.20944/preprints202105.0297.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology 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: Biology And Life Sciences, Biochemistry And Molecular Biology 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: Biology And 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.
ARTICLE | doi:10.20944/preprints202309.0095.v1
Subject: Medicine And Pharmacology, Veterinary Medicine Keywords: Beef calf; Trace mineral supplementation; Passive transfer; Innate immunity; Adaptive immunity; Health status
Online: 1 September 2023 (17:02:37 CEST)
This study compared the relative effect of two trace mineral supplementation strategies recom-mended in France for newborn beef calves. 600 calves were supplemented with 20 mg oral sele-nium (OTM group) at birth (D0) or by injection (ITM group) of a multi-mineral solution (60 mg of Zn, 10 mg of Mn, 15 mg of Cu, 5 mg of Se) on D0, D30 and D60. Mortality and the incidence rate of diseases, including diarrhea, omphalitis, pneumonia, as well as medicinal treatments, were recorded from D0 to D210. The incidence rate of omphalitis was significantly lower in the ITM group than in the OTM group (respectively 11% vs. 17%, P = 0.036). The cumulative inci-dence rate of all health troubles was lower in the ITM group than in the OTM group (P=0.007). Except for pneumonia, incidence of diarrhea (24% vs. 22%), use of oral (7% vs. 6%) or IV rehydra-tion therapy (4% vs. 2%) or use of antibiotics (43.3% vs. 38.0%) and mortality (3% vs 2%) were numerically higher in OTM group than in ITM group (n.s.). In this study, ITM supplementation is as efficient as oral supplementation regarding calves' health status. It reduces the risk of ompha-litis at the calf level effectively.
REVIEW | doi:10.20944/preprints202209.0076.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: innate lymphoid cells; cell therapy; cancer; immunotherapy; antitumor immune response; adoptive cell therapy
Online: 6 September 2022 (03:17:36 CEST)
Although the first cancer immunotherapy was given in the clinic more than a century ago, this line of treatment has remained more of a distant goal than a practical therapy due to limited understanding of the tumor microenvironment and the mechanisms at play within it, which lead to failures of numerous clinical trials. However, in the last two decades, the immune checkpoint inhibitors and chimeric antigen receptor-T cell therapies have revolutionized the treatment of cancer and provided proof-of-concept that immunotherapies are a viable option. So far, immunotherapies have majoritarily focused on utilizing T cells, however T cells are not autonomous but rather function as part of, and therefore are influenced by, a vast cast of other immune cells, including innate lymphoid cells (ILCs). Here, we summarize the role of ILCs, especially helper ILCs, in tumor development, progression and metastasis, as well as their potential to be used as immunotherapy for cancer. By reviewing the studies that used helper ILCs as adoptive cell therapy, we highlight the rationale behind considering these cells as novel adoptive cell therapy for cancer as well as identify open questions and areas for future research.
ARTICLE | doi:10.20944/preprints202007.0618.v1
Subject: Biology And Life Sciences, Immunology And Microbiology 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: Environmental And Earth Sciences, Environmental Science 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: Biology And 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.
REVIEW | doi:10.20944/preprints202311.1527.v1
Subject: Biology And Life Sciences, Virology Keywords: SARS-CoV-2; COVID-19; myeloid-derived suppressor cells; infection; innate immunity; T cells
Online: 23 November 2023 (11:18:17 CET)
Severe COVID-19 is a major cause of morbidity and mortality worldwide, especially to those with co-morbidities, the elderly and the immunocompromised. However, the molecular determinants critical for severe COVID-19 progression remain to be fully elucidated. Meta-analysis of transcriptomic RNAseq and single-cell sequencing datasets comparing between severe and mild COVID-19 patients have demonstrated that the early expansion of myeloid-derived suppressor cells (MDSCs) could a key feature of severe COVID-19 progression. Besides serving as potential early prognostic biomarkers for severe COVID-19 progression, several studies have also indicated the functional roles of MDSCs in severe COVID-19 pathogenesis and possibly even long COVID. Given the potential links between MDSCs and severe COVID-19, we examined the existing literature summarizing the characteristics of MDSCs, the evidence of MDSCs in facilitating severe COVID-19 pathogenesis and discuss the potential therapeutic avenues that can be explored to reduce the risk and burden of severe COVID-19. We also provide a web app where users can visualise the temporal changes of specific genes or MDSC-related gene sets during severe COVID-19 progression and disease resolution at https://temporal-severe-covid.streamlit.app/, based on our previous study described by Ong et al., 2021.
ARTICLE | doi:10.20944/preprints202304.1215.v1
Subject: Biology And Life Sciences, Aquatic Science Keywords: Nucleotides; Saccharomyces cerevisiae derived β-glucan; Vitamins C and E; Innate-immunity; Olive flounder
Online: 29 April 2023 (05:30:03 CEST)
A twelve-week feeding trial was conducted to investigate the effect of dietary supplementation of a functional immunostimulant mixture (FIM; nucleotides, β-glucan and vitamins C and E) on growth, feed utilization, innate immunity, digestive enzyme activity, hematological parameters, intestinal morphology and inflammatory gene expression of olive flounder, Paralichthys olivaceus. A fish meal-based basal diet (control) was formulated and three other diets were prepared by incorporating 0.5, 1.0 and 1.5% FIM into the basal diet (HB0.5, HB1.0 and HB1.5, respectively). Five replicate groups of fish (26.3 ± 0.1 g) were fed one of the experimental diets. Inclusion of 1.5% FIM in the diet significantly enhanced growth and feed utilization. Significantly higher plasma hemoglobin, hematocrit, total protein levels and lower plasma glucose level were observed in HB1.5 group. Total immunoglobulin content, lysozyme, nitroblue tetrazolium, myeloperoxidase, superoxide dismutase, glutathione peroxidase and catalase activities and immune-related gene expressions of toll-like receptor and perforin were significantly increased at highest inclusion level. FIM supplementation significantly increased villus height and goblet cell counts. Anti-inflammatory gene expression was significantly upregulated at a 1.5% level. Dietary supplementation of 1.5% of FIM could improve growth and feed utilization, immune, hematological and histomorphological parameters of olive flounder.
REVIEW | doi:10.20944/preprints202304.1019.v1
Subject: Medicine And Pharmacology, Cardiac And Cardiovascular Systems Keywords: Staphylococcus Aureus Infection, Staphylococcus Aureus Immunity, Staphylococcus Aureus Cytotoxin, Biofilm resistance. Host innate immunity.
Online: 27 April 2023 (03:47:45 CEST)
Staphylococci sp. have become the primary pathogens implicated in infective endocarditis, especially within high-income nations. This along with the increasing burden of healthcare, aging populations and the protracted course the infections may take, contribute to a significant challenge for healthcare systems. A systematic review was conducted using relevant search criteria from PubMed, Ovid’s version of MEDLINE, and EMBASE, and data were tabulated from randomized controlled trials (RCT), observational cohort studies, meta-analysis, and basic research articles. The review was registered with the OSF register of systematic reviews and followed the PRISMA reporting guidelines. 35 studies met the inclusion criteria and were included in the final systematic review. The role of Staphylococcus aureus and its interaction with the protective shield and host protection functions was identified and highlighted in several studies. The interaction between infective endocarditis pathogens, vascular endothelium, and blood constituents was also explored giving rise to the potential use of antiplatelets as preventative and/or curative agents. Several factors allow Staphylococcus aureus infections to proliferate within the host with numerous promoting and perpetuating agents. The complex interaction with the hosts' innate immunity also potentiates its virulence. Ameliorating these molecular pathways may serve as a therapeutic avenue for the prevention and treatment of these infections in near future.
BRIEF REPORT | doi:10.20944/preprints202005.0515.v1
Subject: Biology And 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: Biology And Life Sciences, Immunology And Microbiology 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: Biology And Life Sciences, Immunology And Microbiology 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: Biology And 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.
ARTICLE | doi:10.20944/preprints202308.1764.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Macrophages; LPS; MEK1/2; ERK; IL-1β; H3K9 methylation; Cbx5; Innate immune memory; Tolerance; Priming; Training
Online: 28 August 2023 (10:12:39 CEST)
Macrophages undergo different cellular states upon activation that can be hyporesponsive (tolerated) or hyperresponsive (primed or trained) to subsequent stimuli. Epigenetic modifications are known to play a key role in determining these cellular states. However, little is known about the role of signaling pathways that lead to these epigenetic modifications. Here, we examined the effects of various inhibitors targeting key signaling pathways induced by lipopolysaccharide (LPS) on tolerance and priming in the murine macrophages. We found that a prolonged inhibition (>18 h) of the MEK1/2-ERK signaling axis reversed tolerance and primed cells in expressing IL-1β and other inflammatory cytokines such as IL-6, TNFα, and CXCL10. Ectopic expression of catalytically active and inactive MEK1 mutants suppressed and enhanced IL-1β expression, respectively. Primed cells by the MEK1/2 inhibitor U0126 expressed higher levels of gene sets associated with immune responses and cytokine/chemokine production but lower levels of genes with cell cycle progression, chromosome organization, and heterochromatin formation than non-primed cells. Of interest, expression of the histone 3 lysine 9 (H3K9) methyltransferase Suv39h1 and the H3K9 methylation reader Cbx5 was substantially suppressed, whereas the H3K9 demethylase Kdm7a was enhanced, suggesting a role of the MEK1/2-ERK signaling axis in H3K9 demethylation. The H3K9 trimethylation levels in the genomic regions of IL-1β, TNFα, and CXCL10 were decreased by U0126. Also, the H3K9 methyltransferase inhibitor BIX01294 mimicked and overexpression of Cbx5 prevented the U0126 training effects in both RAW264.7 cells and bone marrow-derived macrophages. Collectively, these data suggest that prolonged inhibition of the MEK1/2-ERK signaling axis reverses tolerance and primed macrophages likely through decreasing H3K9 methylation levels.
REVIEW | doi:10.20944/preprints202308.1012.v1
Subject: Biology And Life Sciences, Other Keywords: PEG10; PEG11/RTL1; RTL/SIRH genes; placenta; brain; innate immunity; human disease; mammalian development and evolution
Online: 14 August 2023 (09:58:16 CEST)
Eutherians have 11 retrotransposon Gag-like (RTL)/sushi-ichi retrotransposon homolog (SIRH) genes presumably derived from a certain retrovirus. Accumulating evidence indicates that the RTL/SIRH genes play a variety of roles in the current mammalian developmental system, such as in the placenta, brain and innate immune system in a eutherian-specific manner. It has been shown that the functional role of Paternally Expressed 10 (PEG10) in placental formation is unique to the therian mammals, as are the eutherian-specific roles of PEG10 and PEG11/RTL1 in maintaining the fetal capillary network and the endocrine regulation of RTL7/SIRH7 (aka Leucine Zipper Down-Regulated in Cancer 1 (LDOCK1)) in the placenta. In the brain, PEG11/RTL1 is expressed in the corticospinal tract and hippocampal commissure, mammalian-specific structures, and in the corpus callosum, a eutherian-specific structure. Unexpectedly, at least three RTL/SIRH genes, RTL5/SIRH8, RTL6/SIRH3 and RTL9/SIRH10, play important roles in combating a variety of pathogens, viruses, bacteria and fungi, respectively, suggesting that the innate immunity system of the brain in eutherians has been enhanced by the emergence of these new components. In this review, we will summarize the function of 10 out of the 11 RTL/SIRH genes and discuss their roles in eutherian development and evolution.
ARTICLE | doi:10.20944/preprints202305.1459.v1
Subject: Medicine And Pharmacology, Endocrinology And Metabolism Keywords: TLR (toll-like receptor) 9; cathelicidin anti-microbial peptide; CAMP; TNFα; adipocyte; adipose tissue; innate immunity
Online: 22 May 2023 (03:55:19 CEST)
Understanding the complex interactions between metabolism and the immune system (“meta-flammation”) is crucial for the identification of key immunomodulatory factors as potential therapeutic targets in obesity and in cardiovascular diseases. Cathelicidin antimicrobial peptide (CAMP) is an important factor of innate immunity and is expressed in adipocytes. CAMP therefore might play a role as an adipokine in metaflammation and adipose inflammation. Toll-like receptor (TLR) 9 is another component of the innate immune system that is expressed and functionally active in adipocytes. The aim of the present study was to investigate the impact of TLR9 signaling on CAMP expression in adipocytes and in adipose tissue. CAMP gene expression in murine 3T3-L1 and human SGBS adipocytes and in murine and human adipose tissues was quantified by real-time PCR. TLR9 knockdown was applied in murine 3T3-L1 adipocytes via siRNA transfection. Adipocyte inflammation was induced in vitro by TNFα stimulation. Serum CAMP concentrations in TLR9 knockout (KO) and in wildtype mice were quantified by ELISA. CAMP gene expression was considerably increased in 3T3-L1 adipocytes during differentiation. TNFα significantly induced CAMP gene expression in mature adipocytes, which was antagonized by inhibitors of NF-κB and PI3K signaling. Cell-free nucleic acids (cfDNA) as endogenous TLR9 ligand significantly impaired CAMP gene expression, whereas synthetic agonistic and antagonistic TLR9 ligands had no effect. Cellular TLR9 knockdown reduced adipocyte CAMP gene expression in vitro and male TLR9 knockout mice exhibited lower systemic CAMP concentrations than wildtype mice. CAMP and TLR9 gene expression were correlated positively in murine and human subcutaneous but not in intraabdominal/visceral adipose tissues. These findings suggest a regulatory role of TRL9 in adipocytic CAMP expression as a novel putative molecular mechanism in adipose tissue innate immunity.
REVIEW | doi:10.20944/preprints201909.0212.v1
Subject: Biology And 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.
REVIEW | doi:10.20944/preprints202311.1496.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: OGG1; NFκB; gene regulation; microenvironment; EMT; innate immunity; cancer stem cells; lung cancer; acute myeloid leukemia; oxidant stress
Online: 23 November 2023 (10:47:24 CET)
8-oxoguanine glycosylase 1 (OGG1), which was initially identified as the enzyme that catalyzes the first step in the DNA base excision repair pathway, is now known also as a modulator of gene expression. What is important for cancer, is that OGG1 acts as a modulator of NFκB-driven gene expression. Specifically, oxidant stress in the cell transiently halts the enzymatic activity of substrate-bound OGG1. The stalled OGG1 facilitates DNA binding of transactivators, including NFκB, to their cognate sites to enable expression of cytokines and chemokines, with ensuing recruitment of inflammatory cells. Recently, we highlighted chief aspects of OGG1 involvement in regulation of gene expression, which have a significance in lung cancer development. However, OGG1 has also been implicated in the molecular underpinning of acute myeloid leukemia. In general, the capacity of cancer cells to adapt to oxidative stress depends on molecular systems such as the interface of OGG1 with NFκB, which bestows a cancer cell with the molecular mechanism of transformation of its microenvironment to enable adaptation and survival of malignant clones.
REVIEW | doi:10.20944/preprints202212.0155.v4
Subject: Biology And Life Sciences, Virology Keywords: covid-19; pandemic; immune evasion; first-line immunity; viral evolution; interferon; dendritic cells; cytokines; chemokines; innate immunity; adaptive immunity; vaccinology
Online: 21 February 2023 (02:38:38 CET)
The SARS–CoV-2 infection has caused both acute and chronic COVID–19 disease during the recent pandemic with emerging more transmissible SARS–CoV–2 Omicron variants (BQ1 and XBB1) that have increased demands for more effective immunogens and therapeutic approaches to protect the lives of numerous SARS–CoV-2 affected individuals and reduce overall disease burden that could be affected by concurrent other pathogens causing diseases. Following a worldwide campaign of mass vaccination, there is still a significant demand to quell the harmful effects of novel SARS–CoV–2 infections due to higher mutation rates within specific areas of the SARS–CoV-2 domain, leading to enhanced viral entry, especially within individuals with one or more significant comorbidities, and there is still a dilemma of how prevention of future pandemics will occur as within host animal mutations and cross species transfer naturally occurs. Concerns intersect at a specific point; a gained evolutionary ability of several viruses over the previous centuries to remain undetected during the first stages of infection by means of capping the 5' end of their DNA and RNA genes respectively. This may occur by reducing the rate of host Type I and Type III Interferons (IFN) cellular synthesis, that would usually occur and affect both apoptotic pathways, that facilitate viral replication and clearance, as well as immune cells, that process and present pathogenic antigen epitopes. Furthermore, although methods of vaccination exist, other methods in clinical development remain that could evoke an immune response in different cellular, serum or mucosal compartments being cellular, serum and mucosal that evoke differential antibody responses. Antibodies are classed as natural and synthetic. Natural antibodies are further classified into neutralizing and non-neutralizing, whilst synthetic antibodies are also further classified into monoclonal and polyclonal. As a result of single cell study transcriptome research, viruses do utilize an array of protein receptors for receptor-mediated cellular entry. This, therefore suggests that potential differential production of antibody immunoglobulins (Ig) within serum and mucosal areas remains affected by cytokines, adhesion molecules and chemokines that can be upregulated or downregulated upon host viral infection. Serum plasma antibodies can be multimeric that may not efficiently cross the nasal epithelium cell layer, therefore offering less protection against mucosal inflammation due to mucin proteins. On the other hand, antibodies produced by mucosal plasma cells at epithelial surfaces are known to provide effective immune responses in some viral infections. The existence of developments that stimulate mucosal immune responses has so far only been seen with influenza nasal immunogens. Nevertheless, scientists developed ways of immunization and early treatment worldwide that generally showed good success rates and fewer risks of adverse events, and the still early present stages of COVID-19 research should also be taken into consideration. For example, the administration of human interferons I and III into the nasal mucosa cellular layer, as key mediators of anti–viral activity, can stimulate cellular activity to train the innate and adaptive immune system cells to develop and appropriately stimulate an adequate immune response through B and T cells. Recently, it was discovered that specific plants secrete proteins that also stimulate the production of Type I Interferons. It might be that focusing on directly offering the immune system the information about the genetics and protein structure of the pathogen, rather than training its first-line mechanisms to develop faster, excessively increases its specificity, making it reach a level that brings the virus the opportunity to evolve and escape previously-developed host immune mechanisms. Naturally-selected polymorphic viruses through genetic recombination pose challenges to traditional concepts of cellular and molecular immune system neutralization of these viruses during the first stages of cellular infection. It is until the scientific community realizes this potentially crucial aspect that we will probably continue to face serious epidemics and pandemics of respiratory diseases over the coming several decades, evidenced with dengue fever and more recently monkeypox. Type I IFNs tend to be produced faster than Type III IFNs, and the first induce slightly more abundant pro-inflammatory signals than the latter, meaning that type III IFNs, if produced early, may further decrease the extent of excessive proinflammatory signals. Hence, we believe that nasal sprays containing a low dosage of Type I and Type III IFNs not only represent a relevant COVID-19 therapeutic, but also a potential unknown modulatory therapy of the future. Of note, it has been indicated that IFN I and / or III display significant immunizing and early therapeutic effects for other viral evoked diseases like Influenza (Influenza (A)H1N1), rabies (Rabies lyssavirus), measles (Measles virus), rubella (Rubivirus rubellae), Hepatitis B, HIV-induced AIDS, Ebola, Marburg, as well as bacterial diseases, such as lower respiratory tract infectious diseases induced by Haemophilus influenzae, Streptococcus pneumoniae and Staphylococcus aureus, and a number of oncological diseases, like hepatic melanoma.
ARTICLE | doi:10.20944/preprints202212.0065.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology 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: Biology And Life Sciences, Immunology And Microbiology 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: Biology And Life Sciences, Immunology And Microbiology 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.
REVIEW | doi:10.20944/preprints202212.0190.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: maternal infection; fetal neurodevelopmental delays; neuroimmunology; innate immunity; adap-tive immunity; interferon; natural lymphocyte; adaptive lymphocyte; neuroprotection; neurogen-esis
Online: 12 December 2022 (04:04:15 CET)
Maternal infectious disease may pose considerable challenges to the fetal health due to the distribution of important elements of the sanguine and lymphatic system from the mother via the umbilical cord. The mother and the fetus have a degree of interdependence that is similar to the one between the eukaryotic cell and the mitochondrion, particularly during the first half term of the pregnancy, which explains the increased appetite of the expecting mother during the first stages of the fetal development. There is a solid bridge between the adaptive immune system and the encephalon that was only discovered a few decades ago. As a result, scientists may still be in the introductory stages of research, and there might be a significant and profound degree of association between the immune system and a healthy neurological development. There is a significant link between the onset of significant maternal infectious disease and the onset of neurodevelopmental disease in the fetus, and virtually all immune cells play major roles in the promotion and inhibition of neurogenesis alike. Likewise, there is a probability that maternal infectious diseases during pregnancy represent a risk factor of fetal neurodevelopmental disease, as a pressurised development of the adaptive immune memory could result in a pressurised or inhibited neurological development, which both can result in a delayed development of certain sub-regions of the brain. For example, the fetus may display poorer social abilities and sharp analytical skills later in life, which is an important sign of neurodevelopmental disease. A pressurised development of the adaptive immune memory could not require the development of a significant form of disease, but rather just a sharp rate of immune preparation against several important pathogenic agents during the introductory stages of life, when the encephalon experiences the sharpest increase rate in development. The problem per se is not the process of immunisation, but a much sharper process of immunisation over the first stages of life in case of an exposure to one dangerous pathogen or more numerous kinds of pathogens and antigens that normally cause moderate disease morbidity. The more dangerous the microbe is, the sharper the development of the adaptive immune memory will be, and the same happens in the case of an increased number of infectious microbes and antigens that infected the cells of the mothers and the fetuses in cause, and this may, in the majority of the situations, still be the case even if the pathogens are already significantly weakened or lifeless, given that the gain of adaptive immune memory alone constitutes an important factor of neurogenesis and an increased rate of neurological development, and that the infant will become almost or fully protected against the pathogens in cause, despite not having had experienced the disease beforehand. In this case, neurodevelopmental delays are possibly not caused by an impaired neurogenesis, but by an excessive one, whilst maternal infection-associated neurodevelopmental delays may be caused by an impaired neurogenesis. Nevertheless, the aetiology of immunity-related neurodevelopmental delays may be more complex in nature and implicate a chronological and spatial sequence of induced excedentary and deficitary rates of neurogenesis, hence reflecting the incredibly complex nature and various forms of neurodevelopmental disease. It is important to mention that a single dose of infant immunisation brings significantly lower risks of adverse neurological events than the onset of a significant maternal infectious disease during pregnancy. The objective of paediatric neuro-immunological studies may be to improve the understanding of the association between a healthy immune developmental rate and a balanced ratio of the developmental rates of important brain regions and sub-regions.
ARTICLE | doi:10.20944/preprints202207.0426.v1
Subject: Computer Science And Mathematics, 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: Biology And 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 And Pharmacology, Immunology And Allergy 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: Social Sciences, 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: Biology And Life Sciences, Biochemistry And Molecular Biology 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/preprints202309.1583.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: lipopolysaccharide (LPS, endotoxin), LPS-binding proteins/peptides, host defence proteins/peptids, innate immune system, marine invertebrates, Gram-negative sepsis, endotoxic shock.
Online: 26 September 2023 (08:12:49 CEST)
Sepsis is a life-threatening complication of an infectious process that results from excessive and uncontrolled activation of the host's pro-inflammatory immune response to a pathogen. Lipopolysaccharide (LPS), also known as endotoxin, which is a major component of the Gram-negative bacteria outer membrane, plays a key role in the development of Gram-negative sepsis and septic shock in humans. To date, no specific and effective drug against sepsis has been developed. This review summarizes data on LPS-binding proteins from marine invertebrates (ILBPs), that inhibit LPS toxic effects, and are of interest as potential drugs for the sepsis treatment. The structure, physicochemical properties, antimicrobial and LPS-binding/neutralizing activity of these proteins and their synthetic analogues are considered in details. Problems that arise during clinical trials of potential anti-endotoxic drugs are discussed.
ARTICLE | doi:10.20944/preprints202307.1356.v2
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Bioactive Lipids; Eicosanoids; Fatty Acids; Mass Spectrometry; Lipidomics; Innate Immunity; Type-I Interferon Response; Chronic Myeloid Leukaemia; Cancer Inflammation; Cancer Metabolism
Online: 31 August 2023 (13:17:58 CEST)
Bioactive lipids are involved in cellular signalling events with links to human disease. Many of these are involved in inflammation under normal and pathological conditions. Despite being attractive molecules from a pharmacological point of view, detection and quantification of lipids has been a major challenge. Here, we have optimised a liquid chromatography dynamic multiple reaction monitoring targeted mass spectrometry (LC-dMRM-MS) approach to profile eicosanoids and fatty acids in biological samples. In particular, by applying this analytic workflow to study a cellular model of Chronic Myeloid Leukaemia (CML), we found that intra- and extra-cellular 2-Arachidonoylglycerol (2-AG), intracellular Arachidonic Acid (AA), and extracellular Prostaglandin F2α (PGF2α), 5-Hydroxyeicosatetraenoic acid (5-HETE), Palmitic acid (PA, C16:0) and Stearic acid (SA, C18:0) were altered in response to immunomodulation by type I Interferon (IFN-I), a currently approved treatment for CML. Our observations indicate changes in eicosanoid and fatty acid metabolism with potential relevance in the context of cancer inflammation and CML.
REVIEW | doi:10.20944/preprints202305.1026.v1
Subject: Medicine And Pharmacology, Endocrinology And Metabolism Keywords: insulin resistance; insulin sensitivity; innate immune system, adaptive immune system, inflammatory response; obesity; visceral adipose tissue; insulin; insulin receptor; insulin signaling
Online: 15 May 2023 (10:37:48 CEST)
The comprehensive anabolic effects of insulin throughout the body, in addition to the control of glycemia, also include ensuring lipid homeostasis and anti-inflammatory modulation, especially in adipose tissue (AT). The prevalence of obesity, defined as a body mass index (BMI) ≥ 30 kg/m2, has been increasing worldwide on a pandemic scale with accompanying syndemic health problems, including glucose intolerance, insulin resistance (IR) and diabetes. Impaired tissue sensitivity to insulin or IR paradoxically leads to diseases with an inflammatory component despite hyperinsulinemia. Therefore, an excess of visceral AT in obesity initiates chronic low-grade inflammatory conditions that interfere with insulin signaling via insulin receptor (INSR). Moreover, in response to IR, hyperglycemia itself stimulates a primarily defensive inflammatory response associated with the subsequent release of numerous inflammatory cytokines and a real threat of organ function deterioration. In this review, all components of this vicious cycle are characterized with particular emphasis on the interplay between insulin signaling and both the innate and adaptive immune responses related to obesity. Increased visceral AT accumulation in obesity should be considered the main environmental factor responsible for the disruption in the epigenetic regulatory mechanisms in the immune system, resulting in autoimmunity and inflammation.
REVIEW | doi:10.20944/preprints201807.0237.v1
Subject: Medicine And Pharmacology, Immunology And Allergy 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 And Pharmacology, Immunology And Allergy 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: Biology And 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.
REVIEW | doi:10.20944/preprints202306.0833.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Cancer-testis-antigens; parthenogenetic; polyploid giant cancer cells; PGCCs; genome fragility; phylostratigraphic analysis; innate immunity-placentation; endogenous retroviruses; sex determination; male infertility; endocrine disruption; environmental pollution
Online: 12 June 2023 (12:59:23 CEST)
The increasing frequency of male cancer coupled with the reduction in male fertility seen worldwide motivated us to seek a potential evolutionary link between these two phenomena, concerning the reproductive transcriptional modules observed in cancer and the expression of cancer-testis-antigens (CTA). The phylostratigraphy analysis of the human genome allowed us to link the early evolutionary origin of cancer by reproductive life cycles of the unicellulars and early multicellulars, potentially driving soma-germ transition, female meiosis and parthenogenesis of polyploid giant cancer cells (PGCCs), with the expansion of the CTA multi-families, very late during evolution. CTA adaptation was aided by retrovirus domestication in the unstable genomes of mammals, for protecting male fertility in stress conditions, particularly that of humans, as compensation for the energy consumption by a large complex brain which also exploited retrotransposition. We found that the early and late evolutionary branches of human cancer are united by the immunity-proto-placental network, which evolved in the Cambrian and shares stress regulators with the finely-tuned sex determination system. We further propose that social stress and endocrine disruption caused by environmental pollution with organic materials, which alter sex determination in male foetuses and further spermatogenesis in adults, bias the development of PGCC-parthenogenetic cancer by default.
REVIEW | doi:10.20944/preprints202309.1883.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: neutrophil extracellular traps (NETs); innate immunity; sepsis; lung disease; cardiovascular disease; liver disease; kidney disease; diabetes; COVID-19; coagulopathy and thrombotic microangiopathy; cancer; autoimmunity; preeclampsia; Kawasaki disease
Online: 28 September 2023 (04:00:59 CEST)
Neutrophils are the principal trouper of innate immune system. Activated neutrophils undergo a noble cell death termed NETosis and release a mesh-like structure called neutrophil extracellular traps (NETs) as a part of their defensive strategy against microbial pathogen attack. This web-like architecture includes a DNA backbone embedded with antimicrobial proteins like myeloperoxidase (MPO), neutrophil elastase (NE), histones etc. and deploys in the entrapment and clearance of encountered pathogens. Thus NETs play an inevitable beneficial role in the host's protection. However, recent accumulated evidence shows that dysregulated and enhanced NET formation has various pathological aspects including promotion of sepsis, pulmonary, cardiovascular, hepatic, nephrological, thrombotic, autoimmune, pregnancy, cancer diseases etc. and the list is increasing gradually. In this review, we summarize NETs mediated pathophysiology of different diseases, focus on some updated potential therapeutic approaches against NETs and share our future perspectives.
REVIEW | doi:10.20944/preprints202304.0807.v3
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: rabies; RABV; PRV; single-stranded RNA; RNA-dependent RNA Polymerase; viral self-camouflaging; glycoprotein; innate immunity; interferon system; natural lymphocytes; adaptive immunity; adaptive lymphocytes; dendritic cells; IgA; IgM; IgG; primary dendritic cells; macrophages
Online: 10 July 2023 (10:09:23 CEST)
Despite being a rare disease worldwide, rabies has the highest morbidity and mortality rates, with nearly all symptomatic cases leading to coma and death. Rabies represents an infectious disease caused by the Rabies virus (RABV), which is part of the Lyssavirus group and the Rhabdoviridae family, and it mainly spreads through the bite and scratch of an infected mammal, but particularly of wild animals, such as bats, foxes, wolves and racoons, and of domestic animals, such as dogs and cats, in rabies-prone areas of the world. Airborne transmission has been deemed as extremely rare, and no clinical case as such has been recorded worldwide yet, except in the enclosed environment, such as research laboratories and caves where infected bats are present. Domestic mammals, such as dogs and ferrets, represent other important reservoirs of disease transmission, and the human cases of Asia and Africa amount approximately 95% of all human cases worldwide. Infected animals most commonly start transmitting the virus once the first symptoms have occurred, and if they experience disease aggravation and death within 10 days, a case of rabies is registered, more easily if the incidence occurred in the urban area and then, any person or animal that had been potentially exposed are strongly recommended to receive the inoculation. It is rare for asymptomatic mammals to transmit the illness. Most First-World and several Second-World countries have recently been declared dog rabies-free by the World Health Organization. The disease can only be treated prophylactically, with three doses of a vaccine containing an inactivated form of RABV, or with five doses of the vaccine and two doses of anti-RABV immunoglobulins within 28 days if the patient is believed to have been exposed to the virus beforehand. It has been projected that, once the viral load reaches elements of the central nervous system, prophylactic approaches are no longer effective, even if symptoms have not begun yet, and this highlights the urgent trait of the medical condition, strongly recommending exposed people to receive the prophylactic doses immediately after the potential exposure to the virus. The pathogen first infects the bodily fluids, before reaching the peripheral nervous system, from where it will gradually move toward the spinal cord or the encephalon, at a speed of movement ranging from 1 to 40 cm per day. It was also found, in extremely rare circumstances, to infect the nasopharyngeal cavity and the lungs. The primary cause of a successful, gradual advance of the viral load toward the point of clinical no-return for the patient - the CNS - is a complex mechanism of induced innate immune evasion, with the interferon system being heavily targeted and silenced by RABV proteins. The ‘Milwaukee’ protocol is locally believed to decrease the mortality rate of the clinical illness to approximately 80%, although significantly more research is required in this sense. First-line immune evasion represents the central mechanism developed by viruses during their evolutionary process to gain control over human immunity, so it could be the development and adjustment of a counter-offensive to this evolutionary operating system that could address the core elements of the problem. Human recombinant Type I and Type III Interferons were found to be significant vaccine adjuvants and to considerably delay the clinical onset of the disease. Despite their central role in natural immunity-based prophylaxis, vaccine support and, in often cases, vaccination per se, a local administration of IFNs as such may not be enough to tackle the core problem of the endemic disease, and a specific and systemic treatment of potential host cells with IFN I and III, as well as IFN-stimulating proteins, may constitute a major research requirement in the coming years of disease investigation, as the inoculation efforts with the inactivated virus and immunoglobulin administration continue. The administration of a relatively low dosage of somatic Natural Killer cells, gamma-interferon and perhaps, of somatic helper CD4+ and somatic cytotoxic CD8+ T-lymphocytes treated with alpha-, beta- and lambda-interferon could be merged with the administration of a similar dosage of alpha-, beta- and lambda-interferon during the efforts to develop an effective and less costly prophylactic vaccine against rabies. A combination of a nasal substance containing a low dosage of IFN I and III with a reduced concentration of neutralized RABV copies, and/or with a low dose of anti-RABV IgA antibodies, could also be tested for humans for the purposes of pre- and post-exposure prophylaxis.