Immune System Receptors Research Articles

High Dose Vardenafil Blunts the Hypertensive Effects of Toll-Like Receptor 3 Activation During Pregnancy

The maternal innate immune system plays a central role in preeclampsia (PE). Toll-like receptors (TLRs) are innate immune system receptors that recognize characteristics of extracellular endogenous ligands or pathogens, and their activation leads to a pro-inflammatory immune response. We and others have reported that excessive activation of TLRs causes pregnancy-dependent hypertension in animals and is associated with PE in women. Activation of TLR3 by poly I:C mimics the innate immune system activation by viruses that women who develop PE encounter during pregnancy. Vardenafil was approved by the FDA for erectile dysfunction but has recently been examined as a potential PE medication due to studies done with a similar drug, sildenafil. Preclinical as well as recent clinical studies demonstrate the potential effectiveness of sildenafil for PE. However, vardenafil is more potent than sildenafil and acts by increasing expression of placental growth factor in addition to increasing cGMP levels. We hypothesized that vardenafil will be more potent and effective in reducing the negative health effects in a mouse model of virus-induced PE. Pregnant mice were injected with the TLR3 agonist poly I:C (PPIC) on gestational days 13, 15, and 17. We treated PPIC mice with a high dose of vardenafil (50 mg human equivalent), a lower dose of vardenafil (20 mg human equivalent), or sildenafil (50 mg human equivalent) on gestational days 15–17 after hypertension was established. Daily i.p. injections of either high dose or low dose vardenafil significantly decreased systolic blood pressure in PPIC mice whereas sildenafil had no effect. There were no differences in body weight between the groups. The splenomegaly induced in PPIC mice was ameliorated in high dose vardenafil-treated PPIC mice, while low dose vardenafil-treated and sildenafil-treated PPIC mice still exhibited splenomegaly. High dose vardenafil-treated PPIC mice also did not exhibit any fetal demise characteristic of PPIC mice, while low dose vardenafil-treated and sildenafil-treated PPIC mice still had significantly increased incidences of fetal demise. These data support the notion that high dose vardenafil may be safe and effective at reducing blood pressure during a virus-associated hypertensive pregnancy.

Walking down Skeletal Muscle Lane: From Inflammasome to Disease.

Over the last decade, innate immune system receptors and sensors called inflammasomes have been identified to play key pathological roles in the development and progression of numerous diseases. Among them, the nucleotide-binding oligomerization domain (NOD-), leucine-rich repeat (LRR-) and pyrin domain-containing protein 3 (NLRP3) inflammasome is probably the best characterized. To date, NLRP3 has been extensively studied in the heart, where its effects and actions have been broadly documented in numerous cardiovascular diseases. However, little is still known about NLRP3 implications in muscle disorders affecting non-cardiac muscles. In this review, we summarize and present the current knowledge regarding the function of NLRP3 in diseased skeletal muscle, and discuss the potential therapeutic options targeting the NLRP3 inflammasome in muscle disorders.

A Primed Subpopulation of Bacteria Enables Rapid Expression of the Type 3 Secretion System in Pseudomonas aeruginosa.

ABSTRACTType 3 secretion systems (T3SS) are complex nanomachines that span the cell envelope and play a central role in the biology of Gram-negative pathogens and symbionts. In Pseudomonas aeruginosa, T3SS expression is strongly associated with human disease severity and with mortality in murine acute pneumonia models. Uniform exposure of isogenic cells to T3SS-activating signal results in heterogeneous expression of this critical virulence trait. To understand the function of such diversity, we measured the production of the T3SS master regulator ExsA and the expression of T3SS genes using fluorescent reporters. We found that heterogeneous expression of ExsA in the absence of activating signal generates a “primed” subpopulation of cells that can rapidly induce T3SS gene expression in response to signal. T3SS expression is accompanied by a reproductive trade-off as measured by increased division time of T3SS-expressing cells. Although T3SS-primed cells are a minority of the population, they compose the majority of T3SS-expressing cells for several hours following activation. The primed state therefore allows P. aeruginosa to maximize reproductive fitness while maintaining the capacity to quickly express the T3SS. As T3SS effectors can serve as shared public goods for nonproducing cells, this division of labor benefits the population as a whole.

Potential role of ocular surface microbiota in keratoconus etiopathogenesis

ABSTRACT Introduction Keratoconus is the most common corneal ectatic disease and the most common cause of corneal transplantation in developed countries. The etiopathogenesis of the disease remains unclear. Areas covered The human body hosts a remarkably abundant and diverse community of microbial species called microbiota. Advances in next-generation sequencing (NGS) technology and bioinformatics have facilitated the characterization of human microbiota. Previous studies have shown that there is an alteration of ocular microbiota in inflammatory and autoimmune ocular diseases. The purpose of this review article is to evaluate the potential effect of ocular microbiota on the pathophysiology of keratoconus. Expert opinion Recent studies have shown the low-level chronic inflammatory process in keratoconus. A regulatory interaction has been demonstrated between human microbiota and Toll-like receptors, which are innate immune system receptors. In addition, Toll-like receptor activity in keratoconus has been shown to be higher than in normal individuals. Therefore, the alteration of ocular microbiota may have a potential role in keratoconus etiopathogenesis. Further research is required on this subject.

PREVALENCE AND CHARACTERISTICS OF TUBERCULOSIS IN HIV-INFECTED PATIENTS CONSIDERING THE 299GLY ALLELE TLR4 GENE CARRIAGE

Human immunodeficiency virus (HIV) infection remains one of the most acute problems of modern medicine. Tuberculosis is known as the leading cause of death among the opportunistic infections in HIV-positive people; moreover, TB is also known as resulting in one of three deaths associated with acquired immunodeficiency syndrome. It should be stressed the TB course against the background of HIV infection demonstrates the atypical characteristics, nonspecific clinical symptoms with increasing frequency of extrapulmonary lesions, minimal radiological manifestations, low frequency of the pathogen excretion, and rapid course of the disease. In recent years, researchers around the world have paid considerable attention to studying the effects of genetic variation of genes on the course of infectious diseases in humans, including HIV and tuberculosis, and in particular, to investigating Tool-receptors, innate immune system receptors, which interact with pathogens and stimulate effector mechanisms of innate immunity. The objective of this study is to determine the prevalence and evaluate the features of the TB course before and during the antiretroviral therapy, considering the carriage of the 299Gly allele of the TLR4 gene. To assess the manifestations, clarify the clinical characteristics of the disease in the dynamics before and during the antiretroviral therapy, a retrospective cohort examination of 181 HIV-positive patients before and after the therapy was carried out. The study has demonstrated that, despite the virological and immunological effectiveness of the treatment, the TB detection in HIV-infected patients taking antiretroviral therapy remained almost constant compared to the period before antiretroviral therapy (17.0% vs. 14.9%, > 0.05). Analysis of genotypes of the TLR4 gene showed that during the observation period before antiretroviral therapy in patients with the 299Gly allele there was a 6.3-fold higher risk of developing of disseminated TB forms (OR = 6.29 [95% 1.20-32.99], p = 0.044), compared with carriers of Asp299Asp genotype. In HIV-infected patients with the 299Gly allele of the TLR4 gene on the background of antiretroviral therapy, the risk of TB development is 3.4 times higher (p = 0.008) than in carriers of its homozygous genotype.

The effect of Kagocel® on gene expression of Toll-like receptors of innate immunity in THP-1 human monocytes with different levels of differentiation

Kagocel® is used in Russia for the treatment of viral infections. In terms of its chemical structure, Kagocel® active ingredient is a copolymer of gossypol polyphenol and carboxymethylcellulose. The study investigated antiviral and cytokine-inducing activity of Kagocel®, as well as its toxic effects. The aim of the study was to investigate the effect of Kagocel® active ingredient on the induction of expression of the innate immune system receptor genes (Toll-like receptors, TLR) in the THP-1 human acute monocytic leukemia cell line with different levels of differentiation. Materials and methods: the effect of Kagocel active ingredient was investigated at the concentrations of 0.2 and 2 mg/mL in the THP-1 human acute monocytic leukemia cell line with different levels of differentiation: non-differentiated monocytes, and monocytes differentiated into macrophage-like cells. Comparative analysis of the activity of TLR 2, 3, 4, 7, 8, 9 genes was carried out by quantitative RT-PCR. The study determined standard deviations of the levels of gene expression in the experimental cells (2deltaCq ± SD) relative to the expression in the control cells. Results: Kagocel active ingredient at the concentration of 0.2 mg/mL induced activation of TLR2 expression in THP-1 monocytes by 3.5 times, TLR3 by 2 times, TLR4 by 1.6 times, and at the concentration of 2 mg/mL also induced activation of TLR7 and TLR8 by 1.4 times, and TLR9 by 2 times. The levels of TLR2, TLR3, TLR9 induction were significantly higher in THP-1 monocytes partially differentiated into macrophage-like cells, and the highest stimulation level was observed for TLR2 (8 times). Conclusions: the results obtained characterise Kagocel® as a stimulator of TLR genes in the THP-1 cell line. The number of TLR genes induced in THP-1 monocytes was shown to increase with the increase in the product concentration. THP-1 monocyte differentiation into macrophage-like cells enhances susceptibility to Kagocel®. The positive regulation of TLR genes activity may account for antiviral and interferon-inducing properties of Kagocel®, and also suggests the possibility of expanding the use of the product for various immune-associated diseases.

In silico design of a multi-epitope peptide construct as a potential vaccine candidate for Influenza A based on neuraminidase protein.

Designing an effective vaccine against different subtypes of Influenza A virus is a critical issue in the field of medical biotechnology. At the current study, a novel potential multi-epitope vaccine candidate based on the neuraminidase proteins for seven subtypes of Influenza virus was designed, using the in silico approach. Potential linear B-cell and T-cell binding epitopes from each neuraminidase protein (N1, N2, N3, N4, N6, N7, N8) were predicted by in silico tools of epitope prediction. The selected epitopes were joined by three different linkers, and physicochemical properties, toxicity, and allergenecity were investigated. The final multi-epitope construct was modeled using GalaxyWEB server, and the molecular interactions with immune receptors were investigated and the immune response simulation assay was performed. A multi-epitope construct with GPGPGPG linker with the lowest allergenicity and highest stability was selected. The molecular docking assay indicated the interactions with immune system receptors, including HLA1, HLA2, and TLR-3. Immune response simulation detected both humoral and cellular response, including the elevated count of B-cells, T-cell, and Nk-cells.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40203-021-00095-w.

Destination active chromatin: RAG2 regions that pave the way to V(D)J recombination

Abstract V(D)J recombination is required to establish the diversity of antigen receptors in the adaptive immune system. Recombination activating gene 2 (RAG2), a protein subunit of the nuclear V(D)J recombinase, rearranges gene segments to generate functional genes that encode antigen receptors. Based on our previous results, we hypothesized that a negatively charged region (the acidic hinge) in RAG2 functions to regulate localization of the V(D)J recombinase with chromatin. To test this, we generated the acidic hinge mutant 1 (A1; D/E 370–383 A), acidic hinge mutant 2 (A2; D/E 404–410 A), and D400H (a known mutation that causes immunodeficiency) to determine impact on chromatin association and V(D)J recombination activity. Dynamics of RAG2 mobility with the chromatin were determined with fluorescence recovery after photobleaching (FRAP) experiments with stably expressed GFP-tagged wild type (WT) or mutant RAG2 in RAG2−/− pro-B cells. Changes in V(D)J recombination activity and in RAG2 localization was determined for cells expressing the WT versus mutant RAG2 proteins. FRAP experiments indicated that the acidic hinge mutants had more tightly bound interactions with chromatin, as compared to WT RAG2. A1 resulted in increased V(D)J recombination, whereas, A2 and D400H led to decreased V(D)J recombination. Interestingly, these results correlated with an increased and a decreased nuclear localization of A1 and A2, respectively, relative to WT RAG2. These results indicate that the acidic region has a role in the cellular localization of the V(D)J recombinase, affecting its recombination efficiency. However, D400H localized similarly to WT RAG2, indicating the residue has a more direct role in the nuclear function of the V(D)J recombinase.

18 Relative expression of the neonatal crystallizable fragment receptor (FcRn) in equine tissues

The neonatal crystallizable fragment receptor (FcRn) is an important immune system receptor with several functions including bi-directional transport of immunoglobulin G across cell surfaces and involvement in antigen presentation. Research regarding the FcRn is robust in human medicine, but has lagged in livestock species. Although the FcRn has been characterized in several body tissues in cattle, sheep and pigs, there is only one published report regarding examination of the FcRn in intestine from a single horse in China. Therefore, the objective of this study was to identify relative FcRn mRNA expression in various equine body tissues. To meet the objective, tissues were collected from 2 horses (H1, H2) within 30 min of euthanasia. Collection sites were standardized for each location to minimize variation. Tissues included lung (4 locations), stomach (2 locations), small intestine (3 locations), cecum (3 locations), large colon (6 locations), and joints (2 locations). A minimum of 5 tissue samples (500 mg each) were collected from each location to obtain representative samples and preserved in RNAlater. Total RNA was extracted using the RNeasy Plus Universal Mini Kit (Qiagen). Reverse transcription to cDNA was performed with the High-Capacity cDNA Reverse Transcription kit (ThermoFisher Scientific). Pre-designed TaqMan probe sets for FcRn (Assay ID 07049868_g1) and 3 reference genes (ACTB, GADPH, HPRT1) were obtained from ThermoFisher Scientific. Relative quantification of mRNA expression of FcRn in each tissue was measured by qPCR using TaqMan Fast Advanced Master Mix (ThermoFisher Scientific) and calculated using the 2 −ΔΔCT method and normalized to the geometric mean of the 3 reference genes. Realtive quantity (RQ) of FcRn expression for tissues from the 2 horses was grouped qualitatively into high, moderate, and low designations. RQ of FcRn expression was highest in the joints (RQ range 2.37–3.98) and small intestine (RQ range 2.28–3.18) with individual variation present in the duodenum (H1 RQ 2.60; H2 RQ 0.82) and ileum (H1 RQ 1.08; H2 RQ 2.47). FcRn expression was moderate in tissues from the cecum (RQ range 1.02–1.75) and lung (RQ 1.42–2.32) with individual variation present in the distal cecum (H1 RQ 1.02; H2 RQ 0.67) and main bronchi tissue (H1 RQ 2.06; H2 RQ 0.47). Expression was lowest in the stomach (RQ range 0.24–1.12) and colon (RQ range 0.56–1.35). FcRn location within specific cell types was not determined and requires further examination. In summary, this novel qualitative study indicates FcRn expression in numerous equine tissues and provides base knowledge from which to expand future investigation.

Toll-Like Receptors Recognize Intestinal Microbes in Liver Cirrhosis.

Liver cirrhosis is one major cause of mortality in the clinic, and treatment of this disease is an arduous task. The scenario will be even getting worse with increasing alcohol consumption and obesity in the current lifestyle. To date, we have no medicines to cure cirrhosis. Although many etiologies are associated with cirrhosis, abnormal intestinal microbe flora (termed dysbiosis) is a common feature in cirrhosis regardless of the causes. Toll-like receptors (TLRs), one evolutional conserved family of pattern recognition receptors in the innate immune systems, play a central role in maintaining the homeostasis of intestinal microbiota and inducing immune responses by recognizing both commensal and pathogenic microbes. Remarkably, recent studies found that correction of intestinal flora imbalance could change the progress of liver cirrhosis. Therefore, correction of intestinal dysbiosis and targeting TLRs can provide novel and promising strategies in the treatment of liver cirrhosis. Here we summarize the recent advances in the related topics. Investigating the relationship among innate immunity TLRs, intestinal flora disorders, and liver cirrhosis and exploring the underlying regulatory mechanisms will assuredly have a bright future for both basic and clinical research.

Molecular Insights of Immune Responses Variability in COVID-19 Patients: A Review

Currently, a novel coronavirus disease 2019 (COVID 19) caused by SARS-CoV-2 has emerged worldwide. This chronic viral infection causes an acute respiratory distress syndrome (ARDS) which its pathophysiology is not yet well elucidated. However, ARDS has shown that ARDS causes diffuse alveolar damages induced by an excessive inflammatory response and a lack of anti-inflammatory response to the virus. Furthermore, these pathophysiological characteristics are associated with multiorgan failure and can increase the mortality rate. The difference in immune system response against COVID-19 is not well known. However, variability in innate immune system receptors between patients infected with SARS-CoV-2 as a function of aging and sex can explain this difference. Thus, innate immune memory or trained immunity mediated by epigenetic mechanisms is also involved in the variability response against COVID-19. The action of an adaptative immune response, in particular, antigen presentation via HLA is also a key element in this variability. Finally, each viral strain's capacity in evading the action of the immune response has also been suggested as an important mechanism by which certain patients infected with SARS-CoV-2 develop severity and others did not develop any clinical symptoms.

Recognition of DAP and activation of NF-κB by cytosolic sensor NOD1 in Oreochromis niloticus

As a lower vertebrate, the immune defense mechanism of fish mainly depends on the innate immune system. Nucleotide-binding oligomerization domain-like receptors (NLRs) are an important class of pattern recognition receptors in the innate immune system. In this study, NOD1 gene was cloned and characterized in Nile tilapia (Oreochromis niloticus). The ORF of Nile tilapia NOD1 gene was 2826 bp long and encoded 941 amino acid residues with a structure of CARD-NACHT-LRRs that was similar to the other counterparts in mammals and fishes. Phylogenetic and synteny analysis showed that NOD1 was conserved among different fishes and existed at least in the early stage of fish evolution. Expression pattern revealed that NOD1 mRNA was constitutively expressed in the tested tissues, while had high expression level in main immune organs and mucosal immune tissues (liver, head kidney, spleen, blood, gill, and intestine). Following Streptococcus agalactiae challenge, Nile tilapia NOD1 mRNA expression levels were altered in immune organs (liver, head kidney, spleen, blood), and the expression pattern was similar in liver, spleen and blood. Furthermore, the ligand recognition and signaling pathway of Nile tilapia NOD1 were also analyzed, it showed that NOD1 could recognize Tri-DAP intracellularly and activated NF-κB signaling pathway. In summary, our results indicated that the Nile tilapia NOD1 may play an important role in innate immune system and provided a basis for the functional study of NOD1 in teleost.

The role of Tоll-like receptors of types 2 and 4 in the pathogenesis of the progressive stage of various clinical types of psoriasis

The article reviews current views on the role of Tоll-like receptors in the innate immune system, discusses their role in psoriasis. We also present our own data on the determination of Tоll-like receptors of 2 and 4 types in the blood of patients with various clinical forms of psoriasis in the advanced stage. In determining the leading criteria for the etiopathogenesis of psoriasis by establishing the role of Toll-like receptors (TLR) triggering exogenous psoriasis factors that can activate different types of immune cells, it was found that the expression level of TLR2 and TLR4 in different clinical forms of psoriasis in the advanced stage differed, namely: there was a tendency to increase the expression of TLR4 on lymphocytes (8±0.31 mfi) and almost did not differ from the control values (3.3±0.26 mfi) at lPsV (3.5±0.29 mfi). Statistically significant results were obtained to increase the expression of TLR4 in other clinical forms of psoriasis in the advanced stage: with PsP the level of TLR4 expression was increased 3.2 times, with PsG – 2.8 times, with PsE – 2.7 times, at dPsV – 2 times compared with the control. When determining the expression of TLR2 on lymphocytes, it was found that its level significantly exceeded similar indicators of the control group: with PsP and PsG – 2 times, with PsE – 1.6 times, with dPsV – 2 times, with PsF and lPsV – 1.5 times. The results obtained from the study can be explained by the fact that TLR2 and TLR4 are activated by pathogenic factors of microorganisms that grow on both affected and intact areas of the skin of patients with psoriasis in the advanced stage of the disease, their expression is increased by proinflammatory cytokines. A slight increase in TLR4 expression in lPsV and PsF may be associated with excessive stimulation of Toll receptors by exogenous ligands before or at the onset of the disease and the development of TLR refractory in the subsequent development of disease and in some cases is a protective response to hyperergic inflammation. Keywords: psoriasis, Toll-like receptors, immunity, erythroderma.

Prevalence of Human Herpes Virus 8 Infection and Pattern of TLR4 rs4986791 Polymorphism in Women with Breast Cancer

Background: Breast cancer is a major cause of female death worldwide. Several factors contribute to cancer development, one of the most important of which is viruses identified by the host immune system and Toll-like receptors (TLRs). Human herpes virus 8 (HHV-8) is one of the viruses with a proven role in Kaposi’s sarcoma development. Objectives: This study aimed to investigate the correlation between HHV-8 infection and breast cancer, as well as the role of rs4986791 polymorphism in women’s health. Methods: Blood samples of 80 healthy subjects and 80 patients suffering from breast cancer were collected (from May-September 2018). The presence of HHV-8 in the samples was examined by PCR. Also, the rs4986791 polymorphism was evaluated by nested PCR-RFLP. Results: The results showed a significant relationship between age and breast cancer. Of 80 cancer patients and 80 healthy subjects, 17 (21.3%) and 15 (18.8%) were carriers of HHV-8, respectively. Also, there was no significant relationship between HHV-8 infection and breast cancer (P = 0.693). We found no significant relationship between the presence of virus and cancer grade (P = 0.618). Conclusions: The results of rs498679 polymorphism analysis indicated that the T allele was associated with increased health phenotype and decreased risk of cancer development. Also, women with TT genotype exhibited significantly lower HHV-8 infection than the other genotypes.

The role of IL-10 in immune responses against Pseudomonas aeruginosa during acute lung infection.

Pseudomonas aeruginosa is considered an opportunistic pathogen of great clinical importance. The clearance of this bacterium occurs through recognition of the pathogen by innate immune system receptors, leading to a lung inflammatory response. However, this response must be controlled via immunoregulatory pathways. In this study, we evaluate the role of endogenous murine IL-10 after acute infection with the virulent strain P. aeruginosa PA14. To assess the role of IL-10, intratracheal infection with the PA14 strain was performed in C57BL/6 or IL-10 KO mice. The PA14 strain was recovered in both types of animals, although IL-10 KO mice presented a higher number of viable bacteria in the lung when compared to the C57BL/6 group. Histopathological and stereological analyses showed that IL-10 KO mice had higher tissue damage and inflammatory infiltrate when compared to control animals. The activity of MMP-9 but not MMP-2, as well as IL-6 and TNF-α expression, were augmented in the lungs of infected animals and was much more evident in IL-10 KO animals when compared to the other analyzed groups. This work indicates that endogenous IL-10 control P. aeruginosa infection, the expression of pro-inflammatory genes, MMP-9 activity and histopathological processes of the infectious process in question.

Uroprotective mechanisms of natural products against cyclophosphamide-induced urinary bladder toxicity: A comprehensive review.

One of the widely used anticancer drugs for the treatment of various neoplasms is cyclophosphamide (CYP). The inactive prodrug CYP is metabolized by cytochrome P450 enzyme into active metabolites, phosphoramide mustard and acrolein. The accumulation of acrolein metabolite inside the urothelium results in hemorrhagic cystitis (HC) which is a urotoxic adverse effect associated with the use of CYP. To counteract the occurrence of HC induced by CYP, Mesna is usually used, with allergic reactions reported in some cases. Therefore, several natural products have drawn much attention as alternative safe therapies to reduce the urotoxicity produced from the use of CYP. This review will focus on certain uroprotective mechanisms related to some medicinal plants that are used to ameliorate the CYP-induced urotoxicity in experimental models. The mechanisms involving oxidative stress, inflammation, immune system, apoptosis, DNA fragmentation, uroplakins, purinergic signaling and muscarinic receptors, and CytoP450 metabolism are discussed.

NF-κB signaling induces inductive expression of the downstream molecules and IgD gene in the freshwater carp, Catla catla.

Toll-like receptors (TLRs) in innate immune system act as primary sensors in detecting the microbial components and activate their signaling cascades to induce NF-κB (nuclear factor NF-κB) towards the augmentation of immunoglobulin (Ig) synthesis. To gain insights into the efficacy of NF-κB pathway in immunoglobulin D (IgD) synthesis in the Indian Major Carp Catla catla, cloning and sequencing of TLR-signaling downstream molecules [TRAF3 (TNF receptor-associated factor 3), NEMO (nuclear factor-kappa B essential modulator), NF-κB and BAFF (B cell activating factor)] were performed by infecting the fish with pathogens. mRNA expression analysis of the downstream molecules and IgD showed significant up-regulation of these genes in kidney (P ≤ 0.001) as compared to spleen (P ≤ 0.05). To ascertain the role of NF-κB pathway in IgD synthesis, the primary cell culture of kidney and spleen in monolayer cell suspension was treated with NF-κB inhibitor (BAY 11-7082) and down-regulation of BAFF, NEMO, NF-κB, and IgD gene was observed. These results highlight the importance of NF-κB signaling pathway in augmenting the IgD gene expression in the freshwater carp, Catla catla.

Constitutive immune mechanisms: mediators of host defence and immune regulation.

The immune system enables organisms to combat infections and to eliminate endogenous challenges. Immune responses can be evoked through diverse inducible pathways. However, various constitutive mechanisms are also required for immunocompetence. The inducible responses of pattern recognition receptors of the innate immune system and antigen-specific receptors of the adaptive immune system are highly effective, but they also have the potential to cause extensive immunopathology and tissue damage, as seen in many infectious and autoinflammatory diseases. By contrast, constitutive innate immune mechanisms, including restriction factors, basal autophagy and proteasomal degradation, tend to limit immune responses, with loss-of-function mutations in these pathways leading to inflammation. Although they function through a broad and heterogeneous set of mechanisms, the constitutive immune responses all function as early barriers to infection and aim to minimize any disruption of homeostasis. Supported by recent human and mouse data, in this Review we compare and contrast the inducible and constitutive mechanisms of immunosurveillance.

Expression of Cytokines in Porcine Iris, Retina and Choroidal Tissues Stimulated by Microbe-associated Molecular Patterns

ABSTRACT Purpose The innate immune system is strongly implicated in the pathogenesis of uveitis. This study was designed to clarify the responses of the innate immune system in uveal tissues. Materials and Methods We utilized quantitative, real-time RT-PCR to measure mRNA of innate immune system receptors from porcine iris, choroid, and retina tissues. We used RT-PCR for cytokines to evaluate the responses of these tissues to specific ligands or extracts of whole bacteria that activate the innate immune system. We used ELISA for IL-6 on selected choroidal supernatants to confirm that the mRNA measurement correlated with protein levels. Results In each of the studied tissues, we detected the expression of important receptors belonging to the innate immune system including dectin-1, TLR4, TLR8, and NOD2. Relative mRNA expression was generally lower in the retina compared to iris or choroid. All three tissues demonstrated upregulation of cytokine mRNA in response to a range of ligands that activate the innate immune system. The measurement of IL-6 protein was consistent with results based on mRNA. Notably, the expression of mRNA for IL-23 was more pronounced than IL-12 in all three tissues after stimulation with various innate immune system ligands. Conclusions These data provide evidence of a potent innate immune response intrinsic to uveal tissues. Specific innate immune system ligands as well as bacterial extracts enhanced the production of several inflammatory cytokines. Furthermore, the observation of higher upregulation of IL-23 mRNA, compared to IL-12 in response to innate immune stimuli, suggested that a local TH17 response might be more robust than a local TH1 response in uveal tissues. Our results expand the understanding as to how the innate immune system may contribute to uveitis.

Bioinformatics Approach for Identifying Novel Biomarkers and Their Signaling Pathways Involved in Interstitial Cystitis/Bladder Pain Syndrome with Hunner Lesion.

The complexity of interstitial cystitis/bladder pain syndrome (IC/BPS) has led to considerable uncertainty in terms of diagnosis and prevalence of the condition. Here, we try to identify the IC/BPS-associated genes through an integrated analysis of Gene Expression Omnibus (GEO) datasets and confirm experimentally to predict the pathologic diagnosis of IC/BPS. Data mining analysis of GEO datasets (GSE621, GSE11783, GSE28242, and GSE57560) revealed a total of 53 (51 upregulated and two downregulated) common differentially expressed genes (DEGs) in IC/BPS. A protein–protein interaction (PPI) network was then constructed with the 53 common DEGs using Cytoscape v3.7.2, and subsequently, six hub genes (CD5, CD38, ITGAL, IL7R, KLRB1, and IL7R) were identified using cytoHubba v0.1 that were upregulated in IC/BPS. Enrichment analysis of common DEGs revealed that hematopoietic cell lineage, immune system, and T-cell receptor (TCR) signaling in naïve CD4+ T cell signaling pathways were prominently involved with the common 51 upregulated DEGs. The two common downregulated DEGs may enrich linoleic acid metabolism and synthesis of epoxy (EET) and dihydroxyeicosatrienoic acid (DHET) signaling pathways in IC/BPS. Moreover, our RT-PCR data confirmed that the expression of the five hub genes (CD38, ITGAL, IL7R, KLRB1, and IL7R) was significantly augmented in IC/BPS patients’ samples when compared with their normal counterparts. In this study, we systematically predict the significant biomarkers and possible signaling pathways involved in IC/BPS, confirming the differential expression of the hub genes in tissue samples from patients with IC/BPS. Thus, the hub genes might be used as potential diagnostic biomarkers of IC/BPS.