A -819 C/T polymorphism in the interleukin-10 promoter is associated with persistent HBV infection, but -1082 A/G and -592A/C polymorphisms are not: a meta-analysis

Association of IL10 gene polymorphism with the susceptibility to dengue and disease severity in a population with asymptomatic and symptomatic dengue

Infections caused by Orthoflavivirus denguei can either manifest asymptomatically or present a wide spectrum of clinical manifestations. This variety of symptoms results from its complex pathogenesis, which is influenced by viral factors, in addition to host genetics and immunological factors. It is known that anti-inflammatory cytokines can play an immunomodulatory role throughout the course of dengue. Therefore, we investigated the single nucleotide polymorphisms (SNPs) -1082 A/G (rs1800896) and -819 C/T (rs1800871) in the interleukin-10 (IL10) gene and their possible relationship with the development of symptomatic dengue in a Brazilian population. This study, carried out in northeastern Brazil, involved 333 volunteers, including 74 patients with dengue without warning signs (DWWS), 45 patients with dengue with warning signs (DWAS), 85 patients with asymptomatic dengue infection (ASY) and 129 health controls. The genomic DNA was extracted and the SNPs were genotyped using quantitative real-time polymerase chain reaction (qPCR). The data obtained were used to conduct statistical analyses of the genotype and allele frequencies. We observed an association of A/G and G/G genotypes of the -1082 A/G SNP of the IL10 gene with susceptibility to symptomatic dengue and DWAS regarding the asymptomatic dengue. The G allele of this SNP has also been identified as a risk factor for symptomatic dengue, DWWS and DWAS. Regarding the analyses between the SNPs -1082 A/G and -819 C/T of the IL10 gene, there was an association of the G-C haplotype with symptomatic dengue, DWWS and DWAS, as well as a correlation of the A-C haplotype with asymptomatic dengue. Moreover, the data indicate an association between the presence of the G allele and the development of symptoms, compared to those without the G allele. Our results indicate the presence of the G allele of SNP -1082 A/G of the IL10 gene as a risk factor for the clinical development of symptomatic dengue in the studied population and show the importance of genomics association studies involving asymptomatic individuals.

Host Factors in the Natural History of Chronic Hepatitis B: Role of Genetic Determinants

BACKGROUND

The host immune system plays an important role in hepatitis B virus (HBV) infection manifestation. Genetic polymorphisms of several inflammatory cytokines, including TNF-α and IL-10, have been associated with chronic hepatitis B (CHB) progression, although with contradicting results. CHB progression can be categorized into four phases, immune tolerance (IT), immune clearance (IC), low/no replicative (LR), and e-negative hepatitis (ENH), with HBeAg seroconversion as an important milestone. Here, we determined the association of TNF-α (rs1800629) and IL-10 (rs1800896 and rs1800872) SNPs in the context of CHB natural history progression, particularly to HBeAg seroconversion, in Indonesian CHB patients.

METHODS

A total of 287 subjects were recruited and categorized into distinct CHB phases based on HBeAg, viral load, and ALT levels. TNF-α and IL-10 SNPs were determined using PCR-RFLP and confirmed with direct sequencing. The association between SNP genotypes with CHB dynamics was determined using logistic regression presented as odds ratio (OR) with 95% CI.

RESULTS

No significant association was found between IL-10 -592A/C polymorphism and progression of IT and IC to LR, IT and IC to ENH, and LR to ENH phases in all the gene models. IL-10 rs1800896 and TNF-α rs1800629 could not be analyzed using logistic regression. Subjects' age (≥40 years old) was significantly associated with IT and IC to LR (OR: 2.191, 95% CI 1.067-4.578, P = 0.034), IT and IC to ENH (OR: 7.460, 95% CI 3.316-18.310, P < 0.001), and LR to ENH (OR: 5.252, 95% CI 2.010-14.858, P = 0.001). Male gender was associated with LR to ENH (OR: 4.077, 95% CI 1.605-11.023, P = 0.004).

CONCLUSIONS

Age and male gender were associated with CHB phase progression instead of the TNF-α and IL-10 polymorphisms. It would be beneficial to study not only the effect of host determinants but also the viral factor to understand the mechanisms of CHB phase progression.

IL-10 -1082 A/G (rs1800896) Polymorphism is Effective in Clearing Hepatitis B Virus Infection

Background: Hepatitis B Virus (HBV) is a universal health challenge all around the world. Several factors like viral load, genetic characteristics, age, sex, and immune status contribute to variable clinical outcomes of HBV infection. The sequels of HBV infection vary remarkably among persons ranging from the spontaneous deletion of infection to persistent infection. Objective: The present study aimed to evaluate the association of single nucleotide polymorphisms IL10-1082 with HBV clearance. Methods: Sixty subjects with Chronic Hepatitis B (CHB) infection and 60 subjects who spontaneously recovered HBV were enrolled in the study. The IL-10-1082 polymorphisms were determined by Polymerase Chain Reaction with Restriction Fragment Length Polymorphism (PCR–RFLP). Results: The clearance of HBV infection demonstrated a significant association with IL-10-1082 polymorphisms in the GG genotype (P = 0.03), while there was no association with other genotypes. Reduced risk of chronic hepatitis B infection was associated with IL-10-1082 GG (OR: 2.33, 95% CI: 1.07 - 5.09). Besides, IL-10-1082 A/G alleles did not differ clearly between the two study groups (P = 0.07) Conclusions: The IL-10-1082 polymorphisms may be associated with a reduced risk of CHB infection and recovery after HBV infection.

Association of TLR3 (rs3775291) and IL-10 (rs1800871) gene polymorphisms with susceptibility to Hepatitis B infection: A meta-analysis

TLR3 and IL-10 play a crucial role in antiviral defence. However, there is a controversy between TLR3 rs3775291 and IL-10 rs1800871 polymorphisms and the risk of hepatitis B virus (HBV) infection. The purpose of this study is to explore the relationship between the two single nucleotide mutations and the risk of HBV infection by meta-analysis. Medline, EMBASE, Web of Science, CNKI, China Wanfang database were searched for the case-control studies on the relationship between TLR3 rs3775291 and IL-10 rs1800871 polymorphism and susceptibility to HBV, updated to June 2020. The data were analysed by Stata 15.0 software. A total of 22 articles were included. The results showed that in the analysis of IL10 rs1800871 polymorphism and the risk of HBV infection, the pooled OR was 1.21 (95% CI 1.06-1.37), 1.28 (95% CI 1.04-1.56) and 1.20 (95% CI 1.06-1.37) and 1.40 (95% CI 1.07-1.83) in the allele model (C vs. T), dominant model (CC+CT vs. TT), recessive model (CC vs. CT+TT) and homozygous model (CC vs. TT), respectively. There was no statistical significance in the heterozygote model. A subgroup analysis of the Asian population showed similar results. The analysis of TLR3 rs3775291 polymorphism and the risk of HBV showed that in the allele model (T vs. C), the pooled OR was 1.30 (95% CI 1.05-1.61). Except for the recessive model, no significances were found in other genetic models. In conclusion, TLR3 rs3775291 and IL-10 rs1800871 polymorphisms are associated with the risk of HBV. Allele C and genotype CC at IL10 rs1800871 loci, as well as allele T and genotype TT at TLR rs3775291 loci, may increase susceptibility to Hepatitis B infection.

Association between cytokine gene polymorphisms and outcome of hepatitis B virus infection in southern Brazil

A number of studies have demonstrated associations between cytokine gene polymorphisms and outcome of hepatitis B virus (HBV) infection. However, no general consensus has been reached, possibly due to differences between ethnic groups. In this study, 345 individuals living in southern Brazil, including 196 chronic HBV carriers and 149 subjects who had spontaneously recovered from acute infection, were enrolled to evaluate the influence of cytokine gene polymorphisms on the outcome of HBV infection. Most participants were of European descent. Genotyping of IL2-330 G/T, IL4-589C/T, IL6-174 G/C, IL10-592C/A, IL10-1082 A/G, IL17A-197 G/A, IL17A-692 T/C, TNF-α-238 G/A, and TNF-α-308 G/A single nucleotide polymorphisms was performed by using the minisequencing (single base extension) method. By multivariable analysis, a statistically significant association was found between genotypic profile AA + GA in TNF-α-308 and chronic HBV infection (OR, 1.82; 95%CI, 1.01-3.27; P = 0.046). In southern Brazil, the carriers of the -308A allele in the TNF-α gene promoter have a moderately higher risk of becoming chronic carriers in case of HBV infection. In addition, patients with chronic active hepatitis B (n = 60) exhibited a decreased frequency (3.3%) of the TNF-238A allele when compared to that (14.8%) found among asymptomatic HBV carriers (n = 136), suggesting that this could be a protective factor against liver injury (OR, 0.17; 95%CI, 0.04-0.076; P = 0.023). J. Med. Virol. 88:1759-1766, 2016. © 2016 Wiley Periodicals, Inc.