Association between IL-10 gene promoter polymorphism and hepatitis B viral infection in an Egyptian population

Polymorphism of the IL-10 gene in Azeri population of Iran

Background

Interleukin (IL)-10 is one of the key interleukins in the immune system. It plays an anti-inflammatory role in body by inhibition of the synthesis of pro-inflammatory cytokines and reducing the expression of major histocompatibility complex II molecules. The single-nucleotide polymorphism in the gene of this interleukin affects its expression level. Thus, this study was conducted to investigate the IL-10 gene polymorphism at position -1082A/G in Azeri population of Iran.

Methods

Blood samples were taken from 254 healthy and non-relevant Iranian Azeri individuals. After DNA extraction, the frequency of IL-10 genotypes and alleles at -1082A/G position was determined by allele specific-PCR method. Then, q-square test was used to compare allele frequencies and IL-10 genotypes with other populations, and p value of < 0.05 was considered significant.

Results

In Iranian Azeri population, the frequency percentage of AA, AG and GG genotypes in IL-10 gene at the -1082A/G location was 37.4, 43.3 and 19.3%, respectively. The frequency percentage of A and G alleles also were 59.1 and 40.9%, respectively. Based on statistical analysis, frequency of IL-10 genotypes in the current study was very similar to the population of Saudi Arabia, but it had a significant difference with East Asia and Ireland populations.

Conclusion

Results of the present study indicate similar polymorphism of IL-10 genotype with neighbor ethnicities in Middle East country. Based on patients backgrounds mentioned in their questioners, this polymorphism was associated with the susceptibility to asthma and Alzheimer in this population which are common in the region.

Heterogeneity of immune control in chronic hepatitis B virus infection: Clinical implications on immunity with interferon-α treatment and retreatment

Hepatitis B virus (HBV) infection is a global public health issue. Interferon-α (IFN-α) treatment has been used to treat hepatitis B for over 20 years, but fewer than 5% of Asians receiving IFN-α treatment achieve functional cure. Thus, IFN-α retreatment has been introduced to enhance antiviral function. In recent years, immune-related studies have found that the complex interactions between immune cells and cytokines could modulate immune response networks, in-cluding both innate and adaptive immunity, triggering immune responses that control HBV replication. However, heterogeneity of the immune system to control HBV infection, particularly HBV-specific CD8⁺ T cell heterogeneity, has consequ-ential effects on T cell-based immunotherapy for treating HBV infection. Altogether, the host’s genetic variants, negative-feedback regulators and HBV components affecting the immune system's ability to control HBV. In this study, we reviewed the literature on potential immune mechanisms affecting the immune control of HBV and the clinical effects of IFN-α treatment and retreatment.

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.

Genetic associations in chronic hepatitis B infection: toward developing polygenic risk scores

Chronic hepatitis B (CHB) infection results in multiple clinical phenotypes of varying severity. One of the critical gaps in CHB management is the lack of a genetic-based tool to aid existing hepatocellular carcinoma and cirrhosis risk stratification models for patients with active CHB. Such individual predictive models for CHB are plagued by an inherent limitation of discriminatory power that clearly indicates the need for their improvement. In this article, we highlight genetic association studies in CHB that identified HLA and cytokine genetic susceptibility loci to CHB. We advance the position that translating CHB genetic susceptibility loci into polygenic risk scores will be a welcome addendum to the current arsenal of CHB outcome predictive models. We conclude with comments on hurdles that future research efforts should address within the research enclave of CHB and advocate for increased genetic data representation from sub-Saharan Africa.

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.

Human genetic susceptibility to hepatitis B virus infection

Hepatitis B virus (HBV) infection is still a serious health threat worldwide. The outcomes of HBV infection consist of spontaneous HBV clearance and chronic HBV infection. Multiple factors contribute to the disparity of HBV infection outcomes, including host factors, viral factors and environmental factors. The present review comprehends the current researches mainly focusing on the relationships between genetic determinants, including single nucleotide polymorphisms (SNPs) and haplotypes, and susceptibility of HBV infection, namely chronic (persistent) HBV infection and HBV clearance. A number of determinants in the chromosomes, including mutations in human leukocyte antigens (HLAs), cytokines genes, toll-like receptors (TLRs), and other genes are related to the human susceptibility to HBV infection. Among the above variants, some of those in HLAs have been studied and replicated in multiple-ethnic populations and came to consistent conclusions, while some others are novel and need to be evaluated further.

Sero-prevalence of human immunodeficiency virus-hepatitis B virus (HIV-HBV) co-infection among pregnant women attending antenatal care (ANC) in sub-Saharan Africa (SSA) and the associated risk factors: a systematic review and meta-analysis

Background

There is plenitude of information on HIV infection among pregnant mothers attending antenatal care (ANC) in sub-Saharan Africa. However, the epidemiology of HBV–HIV co-infections in the same cohort is not clear despite the common route of transmission of both viruses. The aim of our study was to synthesize data on the prevalence of HBV–HIV co-infection among pregnant women attending ANC in Sub-Saharan Africa to assist in the design of public health interventions to mitigate the challenge.

Methods

The study was done in tandem with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) standards and the Cochran’s Q test, I² statistics for heterogeneity and the prevalence were calculated using commercially available software called MedCalcs (https://www.medcalc.org). A random effect model was used to pool the prevalence since all the heterogeneities were high (≥ 78%) and P_het < 0.05 indicated significant heterogeneities. The risk factors and risk differences for HBV–HIV co-infection were analyzed. Any likely sources of heterogeneity were analyzed through sensitivity analysis, meta-regression and sub-group analysis. All analyses were done at 95% level of significance and a P < 0.05 was considered significant.

Results

The overall pooled prevalence of HBV–HIV co-infection among pregnant mothers in sub-Saharan Africa was low 3.302% (95%CI = 2.285 to 4.4498%) with heterogeneities (I²) of 97.59% (P > 0.0001). Within regional sub group meta-analyses, West Africa had significantly higher prevalence of 5.155% (95% = 2.671 to 8.392%) with heterogeneity (I²) of 92.25% (P < 0.0001) than any other region (P < 0.001). Articles published from 2004–2010 had significantly higher prevalence of 6.356% (95% = 3.611 to 9.811%) with heterogeneity (I²) 91.15% (P < 0.0001) compared to those published from 2011 to 2019 (P < 0.001). The HIV positive cohort had significantly higher prevalence of HBV–HIV co-infection of 8.312% (95% CI = 5.806 to 11.22%) with heterogeneity (I²)94.90% (P < 0.0001) than the mothers sampled from the general population with a prevalence of 2.152% (95% CI = 1.358 to 3.125%) (P < 0.001). The overall and sub group analyses had high heterogeneities (I² > 89%, P < 0.0001) but was reduced for South Africa (I²) = 78.4% (P = 0.0314). Age, marital status and employment were independent factors significantly associated with risk of HBV–HIV co-infection (P < 0.001) but not extent of gravidity and education level (P > 0.05). After meta-regression for year of publication and sample size for HBsAg positivity, the results were not significantly associated with HBV pooled prevalence for sample size (P = 0.146) and year of publication (P = 0.560). Following sensitivity analysis, the HBsAg pooled prevalence slightly increased to 3.429% (95% CI = 2.459 to 4.554%) with heterogeneity I² = 96.59% (95% CI = 95.93 to 97.14%), P < 0.0001

Conclusion

There is an urgent need for routine HBV screening among HIV positive pregnant mothers attending antenatal care in sub-Saharan Africa to establish the extent of HBV–HIV co-infection in this cohort. Future studies need to investigate the putative risk factors for HBV–HIV co-infection and prioritize plausible control strategies.

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.

Host Genetic Determinants of Hepatitis B Virus Infection

Chronic hepatitis B virus (HBV) infection is still a major health problem worldwide. Recently, a great number of genetic studies based on single nucleotide polymorphisms (SNPs) and genome-wide association studies have been performed to search for host determinants of the development of chronic HBV infection, clinical outcomes, therapeutic efficacy, and responses to hepatitis B vaccines, with a focus on human leukocyte antigens (HLA), cytokine genes, and toll-like receptors. In addition to SNPs, gene insertions/deletions and copy number variants are associated with infection. However, conflicting results have been obtained. In the present review, we summarize the current state of research on host genetic factors and chronic HBV infection, its clinical type, therapies, and hepatitis B vaccine responses and classify published results according to their reliability. The potential roles of host genetic determinants of chronic HBV infection identified in these studies and their clinical significance are discussed. In particular, HLAs were relevant for HBV infection and pathogenesis. Finally, we highlight the need for additional studies with large sample sizes, well-matched study designs, appropriate statistical methods, and validation in multiple populations to improve the treatment of HBV infection.

Interleukin-6 promotor gene polymorphisms and susceptibility to chronic hepatitis B virus in Egyptians

AIM

To investigate the association between IL-6 polymorphisms (-174G/C, -572G/C and -597G/A) and susceptibility to chronic hepatitis B virus (CHB) infection.

METHOD

Total 108 subjects with CHB infection and 102 healthy controls were enrolled in this study. IL-6 (-174G/C) was genotyped using Mutagenically separated Polymerase Chain Reaction (MS-PCR) while sequence specific primers-PCR (SSP-PCR) was used for studying -572G/C and -597G/A. IL-6 plasma level was measured using Enzyme-linked immunosorbent assay (ELISA).

RESULTS

A significant increase (P < 0.01, P < 0.01, P < 0.001) in -174GG, -572GC and -597GA; respectively in the CHB group compared to control group, while -572GG genotype was significantly decreased (P < 0.01) in CHB patients. A significant increase (p < 0.01, p < 0.01) in -174 G and -597A alleles was observed in the CHB patient group; respectively. GGA haplotype is significantly increased (P < 0.05) while GCA haplotype is significantly decreased (P < 0.001) in the patient group. A moderate linkage disequilibrium (LD) (D' = 0.719, r2 = 0.474; P < 0.001) between IL-6 (-572G/C and -597G/A) was observed. A significant reduction (P < 0.01) in IL-6 plasma level in CHB patients compared to healthy controls (22.28 ± 1.93 versus 32.08 ± 2.41), which was negatively correlated (r = -0.216; P < 0.01) with HBV infection.

CONCLUSIONS

This study pointed to the potential role of IL-6 (-174G/C, -572 G/C and -597G/A) gene polymorphisms in the susceptibility to HBV infection. Our results allow for only preliminary conclusions due to relatively small sample size. There is a need for further larger scale studies to fully examine the possible relationship between these cytokine gene polymorphisms and the development of CHB.

Identification of Functional Genetic Polymorphisms at IL-10 Promoter Region and their Association with Risk of Ischemic Stroke in Chinese Han Population

BACKGROUND

Pleiotropic cytokine interleukin-10 (IL-10) has been suggested as modifying risk for atherosclerosis. Promoter region genetic polymorphism of IL-10 gene is known to be associated with the level of IL-10 production. Through these effects, they might be involved with the ischemic stroke (IS). Our aim was to assess the nature of the functional polymorphisms in IL-10 promoter and any links with IS in Chinese Han population.

METHODS

The IL-10 -1082 G>A, -819 C>T and -592 C>A functional polymorphisms were determined by TaqMan SNP Genotyping assays in 1296 subjects (648 IS patients diagnosed by CTs or/and magnetic resonance imaging (MRI) and 648 normal healthy controls from Chinese Han Population). Multivariate logistic regression analysis was used to show the association between the IL-10 genotypes and the IS events.

RESULTS

We found that the CC genotype of -819 C>T was more common in controls than IS subjects (P<0.05, corrected for multiple testing) in the Han population. CC carriage may be associated with the decreased risk of IS in the Han ethnic group (OR 0.65, 95% CI 0.43-0.97). In addition, the CC genotype in -592 C>A and GG genotype in -1082 G>A are all extremely low in Chinese Han cases and controls.

CONCLUSIONS

The G allele frequency at the -1082 promoter region of IL-10 was rare in Chinese Han population which are diffierent from American/European populations.. IL-10 -819 C>T may be an independent protective factor for IS in the Chinese Han population.

Association of TNF-Alpha gene polymorphisms and susceptibility to hepatitis B virus infection in Egyptians

Tumor necrosis factor alpha (TNF-α) is one of the important cytokine in generating an immune response against hepatitis B virus (HBV). Genetic polymorphisms might influence gene transcription, leading to disturbance in cytokine production. We hypothesized that single nucleotide polymorphism (SNPs) in TNF-α gene could affect the pathogenesis of HBV. To test this hypothesis, we investigated the role of TNF-α polymorphism [-863C/A (rs1800630), -308G/A (rs1800629), -376G/A (rs1800750), -857C/T (rs1799724) and +489G/A (rs1800610)] in the susceptibility to chronic hepatitis B (CHB) infection. Polymorphisms of the TNF-α (-863C/A (rs1800630), -308G/A) were analyzed by Polymerase chain reaction sequence specific primer (PCR-SSP) while TNF-α (-376G/A, -857C/T and +489G/A) by PCR-restriction fragment length polymorphism (PCR-RFLP) in 104 patients with CHB and 104 healthy controls. The plasma level of TNF-α was measured using Enzyme-linked immunosorbent assay (ELISA). The study showed a significant increase in the frequency of -863CC, -376GA, -857CC, -857TT and +489GA genotypes and -863C, -376A, -857C, and +489A alleles in CHB patients compared to controls. In addition, CAGCG haplotype had a highest frequency in CHB patients. A strong Linkage Disequilibrium (LD) between TNF-α -863C/A (rs1800630) and -376G/A (D' = 0.7888, r² = 0.0200); -308G/A and -857C/T (D' = 0.9213, r² = 0.1770); -308G/A and +489G/A (D' = 0.9088, r² = 0.1576) was demonstrated. CHB patients had significantly lower levels of TNF-α compared to controls. In conclusion, our preliminary results suggest that -863C/A (rs1800630), -308G/A, -376G/A, and +489G/A of the TNF-α gene may play a role in HBV susceptibility in Egyptians. The significant reduction in TNF-α in CHB patient was independent of any particular genotype/haplotype in TNF-α.

Inflammatory breast cancer: High incidence of GCC haplotypes (−1082A/G, −819T/C, and −592A/C) in the interleukin-10 gene promoter correlates with over-expression of interleukin-10 in patients’ carcinoma tissues

Interleukin-10 is involved in carcinogenesis by supporting tumor escape from the immune response. The aim of this study was to assess the single nucleotide polymorphisms, −1082A/G, −819T/C and −592A/C, in interleukin-10 gene promoter in inflammatory breast cancer compared to non–inflammatory breast cancer and association of these polymorphisms with interleukin-10 gene expression. We enrolled 105 breast cancer tissue (72 non–inflammatory breast cancer and 33 inflammatory breast cancer) patients and we determined the three studied single nucleotide polymorphisms in all samples by polymerase chain reaction restriction fragment length polymorphism and investigated their association with the disease and with various prognostic factors. In addition, we assessed the expression of interleukin-10 gene by real-time quantitative reverse transcription polymerase chain reaction and the correlation between studied single nucleotide polymorphisms and interleukin-10 messenger RNA expression. We found co-dominant effect as the best inheritance model (in the three studied single nucleotide polymorphisms in non–inflammatory breast cancer and inflammatory breast cancer samples), and we didn’t identify any association between single nucleotide polymorphisms genotypes and breast cancer prognostic factors. However, GCC haplotype was found highly associated with inflammatory breast cancer risk (p < 0.001, odds ratio = 43.05). Moreover, the expression of interleukin-10 messenger RNA was significantly higher (p < 0.001) by 5.28-fold and 8.95-fold than non–inflammatory breast cancer and healthy control, respectively, where GCC haplotype significantly increased interleukin-10 gene expression (r = 0.9, p < 0.001).