Interferon Regulatory Factor 5 Gene Research Articles

Interferon Regulatory Factor 5 Gene Polymorphisms and mRNA Expression Levels Are Associated with Neuromyelitis Optica Spectrum Disorder.

Interferon regulatory factor 5 (IRF5) is a critical transcription factor in the toll-like receptor signaling pathway. It is associated with autoimmune disorders, such as rheumatoid arthritis, systemic lupus erythematosus, and inflammatory bowel disease. However, the relationship between the functional single nucleotide polymorphisms (SNPs) of IRF5 and its mRNA expression level in patients with neuromyelitis optica spectrum disorder remains unclear. The present study aimed to investigate the relationship between polymorphisms and mRNA expression levels of the IRF5 gene with the incidence of neuromyelitis optica spectrum disorder (NMOSD) in northern Chinese Han people. Two loci of the IRF5 gene (rs2004640 and rs2280714) of 164 patients with NMOSD and 269 healthy subjects were genotyped using the multiple SNaPshot technique. The frequencies of alleles, genotypes, and haplotypes were compared. Stratified analysis was performed according to age, sex, AQP4 status, onset age, and Expanded Disability Status Scale (EDSS) score. The IRF5 mRNA levels in peripheral blood mononuclear cells (PBMCs) of 64 NMOSD patients (32 patients in the acute stage and 32 patients in the remission stage) and 35 healthy subjects were detected by real-time PCR. The association of SNP polymorphisms with the mRNA expression level was determined by nonparametric tests. Allele and genotype frequency distributions of rs2004640 showed significant differences between both groups. Compared to healthy controls, the frequency of rs2004640 T allele markedly increased in patients (OR = 1.51, 95% CI = 1.09-2.08, P = 0.005). Minor allele T and GT genotype of rs2004640 that significantly increases the risk of NMOSD were discovered using genetic inheritance models (codominant, dominant, and overdominant) and haplotype analyses. Subsequent haplotype analyses revealed that the major haplotype "T-A" containing the risk alleles (the SNP sequence of the alleles was rs2004640 and rs2280714) had adverse effects on NMOSD. Based on the stratification analysis according to the EDSS score, the GT genotype frequency in the EDSS ≥ 4 group (38.2%) was markedly lower than that in the EDSS < 4 group (61.8%) (OR = 0.32, 95% CI = 0.15-0.68, P = 0.0054), with a significant difference. The IRF5 mRNA expression level was increased in NMOSD patients compared to that in normal subjects. IRF5 gene polymorphisms may be tightly associated with the genesis and progression of NMOSD in northern Chinese Han people. IRF5 mRNA expression was increased in patients with NMOSD and significantly increased in patients with acute phase. Perhaps IRF5 expression levels can be used as a predictor of disease activity in the future.

Correlation Between Gene Expression of Interferon Regulatory Factor-5 and Disease Activity Index in Systemic Lupus Erythematosus Iraqi Patients

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease characterized by elevated levels of circulating anti-nuclear autoantibodies and interferon-alpha (INFs-α). Interferon regulatory factor-5 (IRF5) plays an important role in the induction of type I interferon and pro-inflammatory cytokines, and participates in the SLE pathogenesis. This study aimed to investigate the role of IRF5 gene expression levels in a sample of SLE Iraqi patients and its correlation with disease activity, and to identify its diagnostic ability as a biomarker reflecting disease activity. Blood samples were taken from 45 participants diagnosed with SLE cases classified according to the American College of Rheumatology (ACR) criteria. They were scored via the SLE disease activity index 2000 (SLEDAI-2K) to assess the disease activity and according to it, they were subdivided into “SLE (I) group” (SLEDAI-2k ≤5), and “SLE (II) group” (SLEDAI-2k &gt;5), as well as age and gender matched healthy control group. RNA was isolated from whole blood samples and gene expression levels of IRF5 were determined using real-time polymerase chain reaction (PCR). Our results revealed that the expression levels of the IRF5 gene were significantly increased in SLE (I) and SLE (II) patient groups compared with the control group (p&lt;0.05, and p&lt;0.01) respectively, as well as higher in SLE (II) group than the SLE (I) group (p&lt;0.01). Moreover, the expression levels of IRF5 were found to be related positively and significantly to the disease activity index in both SLE patient groups. The analysis of receiver operator curves (ROC) for gene expression levels of IRF5 in SLE (II) group showed a perfect accuracy to distinguish between SLE patients and healthy individuals (AUC=0.989, sensitivity= 95.5%, and specificity= 88.0%). However, in SLE (I) group showed a good accuracy to discriminate between SLE patients and healthy individuals. (AUC=0.769, sensitivity= 69.6%, and specificity= 80.0%). The correlation between gene expression levels of IRF5 with other parameters revealed that a significant positive correlation was found with uric acid and ALP in SLE (I) group, while in SLE (II) group with urea, creatinine, and uric acid. Our conclusion suggests that the up-regulation of IRF5 gene expression levels correlates positively with disease activity in SLE patients reflecting the possibility of using it as an immunological biomarker for diagnosis, and monitoring the disease flare.

Cascade PID Control Systems Based on DNA Strand Displacement With Application in Polarization of Tumor-Associated Macrophages

Disturbances are widespread in biochemical systems. Nowadays, prevalent single-loop control strategies only take external disturbances into account. However, internal perturbations that threaten the stability of biochemical systems are invariably ignored. In this paper, a DNA strand displacement (DSD)-based cascade PID control system is designed. In addition to traditionally realizing the tracking of reference input and the attenuation of primary disturbance, the presented control approach also innovatively completes the rejection of secondary disturbance. Specifically, the dynamics of the reference input signal are first governed by a first-order low-pass filter integrated with cascade PID control systems, which efficiently avoids the excessive response of the cascaded primary and secondary controllers to the reference signal. Then, cascade PID controllers and second-order time-delay plants are constructed by utilizing the chemical reaction network (CRN) and the DSD. In terms of secondary perturbation suppression, the obtained control scheme significantly outperforms the single-loop PID control scheme with a smaller overshoot and faster settling time. Finally, the DSD-based cascade PID control method is applied to regulate gene expressions of interferon regulatory factor 4 (IRF4) and interferon regulatory factor 5 (IRF5) that affect the polarization of tumor-associated macrophages (TAMs). Compared with the single-loop PID control strategy, the control strategy exhibits a better inhibitory effect on IRF5 gene overexpression (internal disturbance) and TAMs endogenous gene expression (external disturbance).

Relationship of interferon regulator factor 5 and interferon-γ with missed abortion.

The aim of the present study was to reveal the association of missed abortion, a process integrated with the immune system, with interferon regulatory factor 5 (IRF5) and interferon-γ (IFN-γ), and to demonstrate the function of these molecules by examining their levels in decidual tissue. This prospective cohort study included 13 patients with no additional systemic disease, between 6 and 10 weeks of gestation with negative fetal heartbeat, and 11 patients between 6 and 10 weeks of gestation with positive heartbeat who presented for voluntary termination of pregnancy. In the fresh decidual tissue materials recovered after therapeutic curettage, IFN-γ and IRF5 protein levels were determined by ELISA method and IFN-γ and IRF5 gene expression levels by qPCR method. The mean IFN-γ (86.5 vs. 27.3 pg/mg protein; P<0.001) and IRF5 (2.0 vs. 1.5 ng/mg protein; P<0.001) levels were significantly higher in pregnant women who had missed abortion compared to the voluntary abortion group. The increases in the mean IFN-γ/GAPDH (3.5 vs. 1.5-fold increase; P<0.001) and IRF5/GAPDH (3.9 vs. 1.4-fold increase; P<0.001) gene expression levels were significantly higher in the tissues of pregnant women with missed abortion than in the voluntary abortion group. A threshold value of 45.2 pg/mg protein for IFN-γ had a sensitivity of 100% and specificity of 100% in determination of missed abortion. The findings of present study revealed, to the best of our knowledge for the first time in the literature, that IFN-γ and IRF5 may be associated with missed abortion, and that IFN-γ and IRF5 protein levels and gene expression levels were significantly increased in the case of missed abortion. According to our findings, IFN-γ and IRF5 play an important role in placental invasion and pregnancy and can be used as markers for endometrial implantation.

ROLE OF IRF5 GENE POLYMORPHISM IN PREDISPOSITION TO JUVENILE-ONSET SYSTEMIC LUPUS ERYTHEMATOSUS IN THE BELARUSIAN POPULATION

The IRF5 (interferon regulatory factor 5) gene encoding a transcription factor is involved in the regulation of interferon synthesis and other proinflammatory cytokines. It is assumed that the IRF5 gene is associated with juvenileonset systemic lupus erythematosus (jSLE), a chronic autoimmune disease that develops in childhood and differs from the adult subtype of SLE in a number of its manifestations. The aim of the presented work was to conduct a pilot study of IRF5 rs2004640 polymorphism in the population of children in Belarus and its association with the development of jSLE. Genotyping of DNA samples was performed using real-time PCR in a group of patients diagnosed with&#x0D; jSLE (38 people) and in the clinical control group without autoimmune and inflammatory diseases (378 people). The frequency of the IRF5 rs2004640 minor T allele was determined in the Belarusian population of children (under the age of 17). It was found that the rs2004640 TT genotype is associated with the risk of the jSLE development (OR = 2.27; 95% CI 1.08–4.76; p = 0.035) that after further investigations may improve an early diagnosis of jSLE.

Interferon regulatory factor 5 gene variants rs2004640 and rs4728142 are associated with carotid intima media thickness but not with cardiovascular events in rheumatoid arthritis.

Rheumatoid arthritis (RA) is associated with cardiovascular (CV) morbidity and mortality. Interferon regulatory factor 5 (IRF5) gene polymorphisms rs2004640 and rs4728142 have been associated with autoimmune diseases, but also with atherosclerosis. Differences in IRF5 gene expression can lead to the production of different interferons and might play a role in the atherogenic process in RA. We investigated the effects of IRF5 gene variants rs2004640 and rs4728142 on clinical parameters related to atherosclerosis, such as cIMT (in subgroup n=101), and new CV events (in whole cohort n=353). For rs2004640, cIMT values at baseline were highest within the group of patients carrying the GG-genotype, followed by GT- and TT- genotypes, which was statistically significant. Over time patients with the TT-genotype had the highest increase in cIMT. For rs4728142 cIMT values were also the highest for patients with the GG-genotype at baseline, but the difference between the groups was not statistically significant. Over time the highest increase in cIMT was in the patients with the AA-genotype. Both rs2004640 and rs4728142 were not associated with new CV events during follow-up. IRF5 alleles are associated with changes in cIMT, but not with new CV events in RA. Although these findings implicate a role of the IRF5 transcription pathway in atherosclerosis, IRF5 single nucleotide polymorphisms do not appear to increase the risk of future CV events.

Identification and characterisation of single nucleotide polymorphisms in interferon regulatory factor-5 gene of Nigerian local chickens

Abstract The interferon regulatory factor gene family encodes transcription factors with multiple biological functions, which include reproduction, cell differentiation and immunity. Interferon regulatory factor-5 (IRF-5) gene is involved in immune defence against virus, stress response, activation of type I interferon genes, cell differentiation and growth. This experiment was conducted to identify and characterise single nucleotide polymorphisms in exons 3, 4, 5 and 7 of IRF-5 gene in Nigerian local chickens. Exons 3, 4, 5 and 7 of IRF-5 gene were amplified and sequenced. Single nucleotide polymorphisms (SNPs) present in exons 3, 4, 5 and 7 of IRF-5 gene were identified and analysed using Clustal W, DnaSp and SNAP2 software packages. Four SNPs, rs317511101, rs312902332, rs315149141 and rs739389464, were identified in exon 3 of IRF-5 gene in all the three genotypes. Exon 4 of the gene was conserved while three of the SNPs (rs736423928, 170C&gt;T and rs740736761) identified in exon 7 were shared among the three genotypes. Linkage disequilibrium of 1.00 existed between rs317511101 and rs315149141 polymorphisms identified in exon 3 of normal feathered and frizzle feathered chickens. Mutation rs740736761 identified in exon 7 had the highest polymorphism information content obtainable for any biallelic marker. Most of the SNPs identified in exons 3, 5 and 7 were synonymous and singletons which could not be used for association study. The study concluded that only haplotypes in exons 3 and 7 of IRF-5 gene can be used in marker-assisted selection when improving Nigerian local chickens.

Interferon regulatory factor (5) Gene Variants (rs2004640) as Genetic Risk Factor for Systemic Lupus Erythematosus but not Lupus Nephritis in Egyptian adults

Systemic lupus erythematosus (SLE) is an autoimmune disease with complex etiology. Systemic lupus erythematosus (SLE) is an autoimmune disease with complex etiology. Genetic aberrations disrupting the immune regulatory mechanisms may initiate autoimmune disease development. Recent studies have proved that the interferon regulatory factor 5 (IRF5) gene is an important risk factor for SLE. We aimed to investigate the association of the rs2004640 polymorphism within the IRF5 gene with SLE and lupus Nephritis and SLE activity in a sample of adult Egyptian population. 199 individuals were classified into: group I: included 118 patients who were further subdivided into 57 patients with and 61 patients without lupus nephritis respectively and group II: 81 healthy subjects as controls. Genotyping of the SNP rs2004640 at IRF5 gene was analyzed via allele discrimination assay using Real-Time PCR. TT genotype was the most abundant among SLE patients (p=0.001), but GG genotype was the most abundant in controls (p=0.001) while, genotype frequency showed no significant statistical difference between lupus patients with and without nephritis (p= 0.2, 0.1 respectively). The multivariate analysis of prediction of SLE activity [assessed by systemic lupus erythematosus disease activity index (SLEDAI) scoring] showed that the protein/creatinine ratio (95% CI, 0.001 to 0.002) and anti-dsDNA (95% CI, 0.005 to 0.1) were independent factors of SLE activity (OR=0.001 and 0.008 respectively). IRF5 gene polymorphism (rs2004640) might be candidate risk factor for developing SLE but not risk factor for lupus nephritis or the disease activity in a sample of adult Egyptian population.

IRF5 Promotes Influenza Virus-Induced Inflammatory Responses in Human Induced Pluripotent Stem Cell-Derived Myeloid Cells and Murine Models.

Recognition of influenza A virus (IAV) by the innate immune system triggers pathways that restrict viral replication, activate innate immune cells, and regulate adaptive immunity. However, excessive innate immune activation can exaggerate disease. The pathways promoting excessive activation are incompletely understood, with limited experimental models to investigate the mechanisms driving influenza virus-induced inflammation in humans. Interferon regulatory factor 5 (IRF5) is a transcription factor that plays important roles in the induction of cytokines after viral sensing. In an in vivo model of IAV infection, IRF5 deficiency reduced IAV-driven immune pathology and associated inflammatory cytokine production, specifically reducing cytokine-producing myeloid cell populations in Irf5-/- mice but not impacting type 1 interferon (IFN) production or virus replication. Using cytometry by time of flight (CyTOF), we identified that human lung IRF5 expression was highest in cells of the myeloid lineage. To investigate the role of IRF5 in mediating human inflammatory responses by myeloid cells to IAV, we employed human-induced pluripotent stem cells (hIPSCs) with biallelic mutations in IRF5, demonstrating for the first time that induced pluripotent stem cell-derived dendritic cells (iPS-DCs) with biallelic mutations can be used to investigate the regulation of human virus-induced immune responses. Using this technology, we reveal that IRF5 deficiency in human DCs, or macrophages, corresponded with reduced virus-induced inflammatory cytokine production, with IRF5 acting downstream of Toll-like receptor 7 (TLR7) and, possibly, retinoic acid-inducible gene I (RIG-I) after viral sensing. Thus, IRF5 acts as a regulator of myeloid cell inflammatory cytokine production during IAV infection in mice and humans and drives immune-mediated viral pathogenesis independently of type 1 IFN and virus replication.IMPORTANCE The inflammatory response to influenza A virus (IAV) participates in infection control but contributes to disease severity. After viral detection, intracellular pathways are activated, initiating cytokine production, but these pathways are incompletely understood. We show that interferon regulatory factor 5 (IRF5) mediates IAV-induced inflammation and, in mice, drives pathology. This was independent of antiviral type 1 IFN and virus replication, implying that IRF5 could be specifically targeted to treat influenza virus-induced inflammation. We show for the first time that human iPSC technology can be exploited in genetic studies of virus-induced immune responses. Using this technology, we deleted IRF5 in human myeloid cells. These IRF5-deficient cells exhibited impaired influenza virus-induced cytokine production and revealed that IRF5 acts downstream of Toll-like receptor 7 and possibly retinoic acid-inducible gene I. Our data demonstrate the importance of IRF5 in influenza virus-induced inflammation, suggesting that genetic variation in the IRF5 gene may influence host susceptibility to viral diseases.

Evidence of purifying selection in exon 3 of interferon regulatory factor-5 (IRF-5) gene in Nigerian indigenous chickens

Immune genes are under acute selective pressure in order to resist pathogenic attacks. It is not really clear the type of selective force that acts on immune genes because of diverse pathogen load and host population density, so this experiment studied the selective force acting on exon 3 of IRF-5 gene in Nigerian indigenous chickens. DNA was extracted from 90 Nigerian indigenous chickens and exon 3 of IRF-5 gene was sequenced. The region was tested for deviation from neutrality using DnaSP. The Mean non-synonymous substitutions per non-synonymous site (dN) and mean synonymous substitutions per synonymous site (dS) were calculated to predict likely selective force/event acting on the region using HyPhy software implemented inside MEGA6 software. All the test of neutrality indices obtained for exon 3 of IRF-5 gene in Nigerian indigenous chickens were greater than 1 except Tajima’s D value of normal feather chickens (0.93) and Fu’s Fs value of naked neck chickens (0.71). The dN of 0.00 and negative dS were estimated for exon 3 of IRF-5 gene in all the three genotypes. This study therefore concluded that purifying selective forces are acting on exon 3 of IRF-5 gene in Nigerian indigenous chickens.&#x0D; Keywords: Chickens, co-evolution, immunity, pathogens, selection.

IRF5 promoter methylation as a new potential marker of rheumatoid arthritis.

Introduction: The interferon regulatory factor 5 (IRF5) gene is implicated in the toll‑like receptor signaling pathway and has proinflammatory and chemotactic effects, but its role in the pathogenesis of rheumatoid arthritis (RA) remains unclear. Since the pathobiology of RA shares some similarities with other autoimmune diseases, we tested the hypothesis that RA may be associated with IRF5‑related pathways, as has been reported for systemic lupus erythematosus and Sjögren syndrome. Objectives: The aim of the study was to investigate the association between the presence of methylation in the IRF5 promoter and the morbidity and severity of RA as well as with levels of inflammatory markers. Patients and methods: A total of 146 unrelated individuals, 122 patients with RA and 24 healthy controls, were enrolled in the study. All RA patients were genotyped with regard to the following polymorphisms in the IRF5 gene: rs10488631, T>C and rs4728142 G>A. The methylation analysis included 52 patients with RA and 24 healthy controls. A quantitative real‑time methylation‑specific polymerase chain reaction was used to evaluate methylation status. Results: We found differences between patients with RA and healthy controls in the methylation pattern of the promoter region. The methylation level was 43.6% lower in RA patients than in controls (median [interquartile range], 0.79 [0.6-1.13] vs 1.4 [1.16-1.66]; P = 0.0001). Variant rs4728142 G>A was more common in seronegative patients with RA. Conclusions: The methylation profile of the IRF5 promoter may be used as a new potential marker of RA, which is independent of current criteria of disease activity.

Genetic variants of interferon regulatory factor 5 associated with the risk of community-acquired pneumonia

Interferon regulatory factor 5 (IRF5) is a key transcription factor involved in the control of the expression of pro-inflammatory cytokines and immune responses to infection, and multiple polymorphisms of the IFR5 gene have been shown to be associated with autoimmune and infectious diseases. Several studies have investigated single nucleotide polymorphisms (SNPs) in a number of genes associated with the susceptibility to or severity and outcome of community-acquired pneumonia (CAP), but no research has yet been conducted on the role of IRF5 gene polymorphisms in CAP. In this study, we investigated the effects of four IFR5 variants, rs77571059, rs2004640, rs10954213, and rs3807306 on the susceptibility to CAP by genotyping 228 CAP patients and 177 healthy donors. Our results indicated that IFR5 variants rs77571059 and rs2004640 and haplotype GTAA were associated with the susceptibility to CAP and rs77571059 was related to the severity of the disease, suggesting that IFR5 variants may contribute to the pathogenesis of CAP and may serve as prognostic markers of CAP susceptibility and outcome.

Association of IRF5 gene single nucleotide polymorphism with systemic lupus erythematosus susceptibility in Iranian population

BackgroundSystemic lupus erythematous (SLE) is an autoimmune disease characterized by autoantibody production, immune complex deposition, and involvement of the type I interferon (IFN) pathway. Interferon regulatory factor 5 (IRF5) is a transcription factor that regulates the transactivation of type I IFN system-related genes. The association of IRF5 gene single nucleotide polymorphisms (SNP) with SLE has been reported in different populations. The aim of this study was to investigate the association of IRF5 gene rs2004640 SNP with SLE susceptibility in Iranian population. Methods and resultsGenomic DNA was isolated from the peripheral blood leukocytes of 492 patients and 468 healthy individuals using the phenol-chloroform method. The TaqMan allelic discrimination Real-Time PCR method was applied to genotype rs2004640. The frequency of the rs2004640 T allele was significantly higher in SLE patients compared with healthy individuals. Among the rs2004640 genotypes of IRF5 gene, GT and TT genotypes were significantly associated with risk of SLE. Considering the dominant model of TT + GT, the disease risk was elevated significantly. No significant association was observed between rs2004640 genotypes and clinical features. ConclusionThese results confirm that rs2004640 T allele as well as TT and GT genotypes are associated with SLE and seem to significantly increase susceptibility to the disease in Iranian population, as they had associations with SLE proneness in other populations.

Association of interferon regulatory factor 5 (IRF5) gene polymorphisms with juvenile idiopathic arthritis.

Interferon regulatory factor 5 (IRF5) is a member of IRF family which induce signaling pathways and are involved in modulation of cell growth, differentiation, apoptosis, and immune system activity. Juvenile idiopathic arthritis (JIA) is an auto-inflammatory syndrome where the inflammatory markers are believed to play a fundamental role in its pathogenesis. In this study, we aimed to assess the association of IRF5 gene polymorphisms with susceptibility of JIA in Iranian population. Three IRF5 single-nucleotide polymorphisms (rs10954213 A/G, rs2004640 G/T, and rs3807306 G/T) were genotyped using TaqMan assays in 55 patients with JIA and 63 matched healthy individuals. The frequency of the IRF5 rs2004640 T allele was significantly higher (69 vs 45%, P value = 0.0013) in JIA group as compared to control. The frequency of the IRF5 rs 2004640 G allele was significantly higher in the control group in comparison to JIA group (54 vs 32%, P value = 0.001). Allele and genotype frequencies of the rs10954213 and rs3807306 did not show any significant difference between JIA and control group. IRF5 rs 2004640 T allele can be considered as a risk factor for the development of JIA and presence of rs 2004640 G may be act as protective factor.

Expression, polymorphism of IRF5 gene and association with serum cytokine levels in pig

Interferon regulatory factor 5 (IRF5) gene is a crucial transcription factor in immune system and has shown its functionally diverse roles in the regulation of antiviral responses. Previous study revealed the IRF5 gene resides in the reported quantitative trait locus (QTLs) for cytokine levels. In this report, the porcine IRF5 gene was selected to investigate its effect on cytokine level in serum. The mRNA expression of IRF5 was also detected by real time quantitative PCR and the results revealed that IRF5 mRNAs were widely expressed in all analysed tissues except muscle. A genomic variant (g.10764 T > C) in exon 7 of the IRF5 gene was identified by direct sequencing, and then the SNP was genotyped by MALDI-TOF MS assay method in three pig populations. The further association analysis indicated that the SNP was significantly associated with the level of interferon-γ (day 20), interleukin 10 (day 35) and ratio of interferon-γ/interleukin 10 (day 35) in serum (p < .05). An interferon known to be key in immune processes. These results suggested that IRF5 could serve as a promising candidate gene for pig disease resistance breeding.

Association of IRF5 polymorphisms with increased risk for systemic lupus erythematosus in population of Crete, a southern-eastern European Greek island

Interferon regulatory factor 5 (IRF5) regulates type I interferon (IFN)-responsive genes, and has been one of the most consistently associated genes with systemic lupus erythematosus (SLE). We sought to investigate whether IRF5 haplotypes are associated with risk for SLE in the genetically homogeneous Greek population of the island of Crete, as well as whether these haplotypes are associated with increased type I IFN. 322 SLE patients and 247 healthy controls from Crete were genotyped for rs2004640, rs3807306, rs10488631 and rs2280714 SNPs of IRF5 gene by using Taqman primer-probe sets. Type I IFN levels were measured using a functional reporter cell assay. All IRF5 SNPs examined were found to be associated with SLE in univariate case-control analysis. The 4 SNPs formed 5 major haplotypes and the Neanderthal-derived TACA risk haplotype was present in Crete and enriched in the SLE cases (OR=2.01, P=0.0003). Serum IFN levels were measured in a subset of the SLE patients, and carriage of the TACA haplotype was associated with higher circulating type I IFN levels (P=0.037). This study demonstrates the association of IRF5 with an increased susceptibility for SLE in the population of Crete and emphasizes the association of the Neanderthal-derived IRF5 haplotype with SLE susceptibility. Patients carrying allele the Neanderthal allele C had greater type I IFN, supporting a functional consequence of this polymorphism.

Interferon regulatory factor 5 gene polymorphism in Egyptian children with systemic lupus erythematosus.

Background Increased expression of interferon-inducible genes is implicated in the pathogenesis of systemic lupus erythematosus (SLE). Interferon regulatory factor 5 (IRF5) is one of the transcription factors regulating interferon and was proved to be implicated in the pathogenesis of SLE in different populations. Objectives The objective of this study was to investigate the correlation between polymorphisms of the IRF5 gene and SLE susceptibility in a cohort of Egyptian children and to investigate their association with clinico-pathological features, especially lupus nephritis. Subjects and methods Typing of interferon regulatory factor 5 rs10954213, rs2004640 and rs2280714 polymorphisms were done using polymerase chain reaction-restriction fragment length polymorphism for 100 children with SLE and 100 matched healthy controls. Results Children with SLE had more frequent T allele and TT genotype of rs2004640 ( Pc = 0.003 and 0.024, respectively) compared to controls. Patients with nephritis had more frequent T allele of rs2004640 compared to controls ( Pc = 0.003). However the allele and genotype frequencies of the three studied polymorphisms did not show any difference in patients with nephritis in comparison to those without nephritis. Haplotype GTA of rs10954213, rs2004640 and rs2280714, respectively, was more frequent in lupus patients in comparison to controls ( p = 0.01) while the haplotype GGG was more frequent in controls than lupus patients ( p = 0.011). Conclusion The rs2004640 T allele and TT genotype and GTA haplotype of rs rs10954213, rs2004640, and rs2280714, respectively, can be considered as risk factors for the development of SLE. The presence of the rs2004640 T allele increases the risk of nephritis development in Egyptian children with SLE.

Characterization of common carp (Cyprinus carpio L.) interferon regulatory factor 5 (IRF5) and its expression in response to viral and bacterial challenges.

BackgroundCommon carp (Cyprinus carpio L.), one of the most economically valuable commercial farming fish species in China, is often infected by a variety of viruses. As the first line of defence against microbial pathogens, the innate immune system plays a crucial role in teleost fish, which are lower vertebrates. Interferon (IFN) regulatory factor 5 (IRF5) is a key molecule in antiviral immunity that regulating the expression of IFN and other pro-inflammatory cytokines. It is necessary to gain more insight into the common carp IFN system and the function of fish IRF5 in the antiviral and antibacterial response.ResultsIn the present study, we characterized the cDNA and genomic sequence of the IRF5 gene in common carp, and analysed tissue distribution and expression profile of this gene in response to polyinosinic:polycytidylic acid (poly I:C) and lipopolysaccharides (LPS) treatment. The common carp IRF5 (ccIRF5) gene is 5790 bp in length and is composed of 9 exons and 8 introns. The open reading frame (ORF) of ccIRF5 is 1554 bp, and encodes 517 amino acid protein. The putative ccIRF5 protein shares identity (65.4–90.0 %) with other fish IRF5s and contains a DNA binding domain (DBD), a middle region (MR), an IRF-associated domain (IAD), a virus activated domain (VAD) and two nuclear localization signals (NLSs) similar to those found in vertebrate IRF5. Phylogenetic analysis clustered ccIRF5 into the IRF5 subfamily with other vertebrate IRF5 and IRF6 genes. Real-time PCR analysis revealed that ccIRF5 mRNA was expressed in all examined tissues of healthy carps, with high levels observed in the gills and the brain. After poly I:C challenge, expression levels of ccIRF5, tumour-necrosis factor α (ccTNFα) and two IFN stimulated genes [ISGs (ccISG5 and ccPKR)] were up-regulated in seven immune-related tissues (liver, spleen, head kidney, foregut, hindgut, skin and gills). Furthermore, all four genes were up-regulated in vitro upon poly I:C and LPS challenges.ConclusionsOur findings suggest that IRF5 might play an important role in regulating the antiviral and antibacterial response in fish. These results could provide a clue for preventing common carp infection by pathogenic microorganisms present in the aquatic environment.Electronic supplementary materialThe online version of this article (doi:10.1186/s12917-016-0750-4) contains supplementary material, which is available to authorized users.

Mangiferin inhibits macrophage classical activation via downregulating interferon regulatory factor5 expression.

Mangiferin is a natural polyphenol and the predominant effective component of Mangifera indica Linn. leaves. For hundreds of years, Mangifera indica Linn. leaf has been used as an ingredient in numerous traditional Chinese medicine preparations for the treatment of bronchitis. However, the pharmacological mechanism of mangiferin in the treatment of bronchitis remains to be elucidated. Macrophage classical activation is important role in the process of bronchial airway inflammation, and interferon regulatory factor 5 (IRF5) has been identified as a key regulatory factor for macrophage classical activation. The present study used the THP-1 human monocyte cell line to investigate whether mangiferin inhibits macrophage classical activation via suppressing IRF5 expression in vitro. THP-1 cells were differentiated to macrophages by phorbol 12-myristate 13-acetate. Macrophages were polarized to M1 macrophages following stimulation with lipopolysaccharide (LPS)/interferon-γ (IFN-γ). Flow cytometric analysis was conducted to detect the M1 macrophages. Reverse transcription-quantitative polymerase chain reaction was used to investigate cellular IRF5 gene expression. Levels of proinflammatory cytokines and IRF5 were assessed following cell culture and cellular homogenization using enzyme-linked immunosorbent assay. IRF5 protein and nuclei co-localization was performed in macrophages with laser scanning confocal microscope immunofluorescence analysis. The results of the present study demonstrated that mangiferin significantly inhibits LPS/IFN-γ stimulation-induced classical activation of macrophages in vitro and markedly decreases proinflammatory cytokine release. In addition, cellular IRF5 expression was markedly downregulated. These results suggest that the inhibitory effect of mangiferin on classical activation of macrophages may be exerted via downregulation of cellular IRF5 expression levels.

Association between genetic polymorphisms in interferon regulatory factor 5 (IRF5) gene and Malaysian patients with Crohn's disease.

The study aimed to investigate the association between the interferon regulatory factor 5 (IRF5) gene polymorphisms and the onset of Crohn's disease (CD) in a Malaysian cohort. Genomic DNA was extracted from blood samples collected from 91 CD patients and 100 healthy individuals via a conventional phenol-chloroform extraction method. Screening of the four target single nucleotide polymorphisms (SNPs), including rs3807306, rs4728142, rs10954213 and rs11770589 was carried out in a real-time polymerase chain reaction (PCR) thermal cycler using TaqMan genotyping assay. The genetic data obtained was subsequently subjected to statistical analysis to relate the SNPs to the onset of CD in the Malaysian population. The genotyping assay and data were further validated selectively by conventional PCR amplification of the SNP sites and DNA sequencing. The rs3807306 G allele was a risk factor for CD (OR 2.3630, P = 0.00004), whereas the homozygous T genotype was protective against the disease (OR 0.2038, P = 0.00004). The heterozygous A/G genotype of rs10954213 was significantly associated with CD (OR 4.319, P = 0.0377). On the other hand, the homozygous A and heterozygous A/G genotypes of the rs11770589 were significant in the controls (OR 0.4242, P = 0.0166) and patients (OR 2.000, P = 0.0179), respectively. In the ethnic-stratification analysis, the rs11770589 homozygous A genotype was protective in Indians (OR 0.1551, P = 0.0112). IRF5 gene polymorphisms may play a role in the development of CD in the Malaysian population.