Cytokine gene polymorphisms in patients infected with hepatitis B virus

Strategy for immunological analysis of pro-inflammatory cytokine marker studies with chronic hepatitis B virus in Southwestern region of Saudi Arabia

BACKGROUND

Hepatitis B Virus (HBV) is one of the leading causes of infectious disease in the global population, and its prevalence has been increasing globally. Human HBV infection is complex, involving both innate and adaptive immune systems. Cytokines play a role in both physiologic and pathologic processes in the liver. This study was designed to screen serum levels using an enzyme linked immunosorbent assay (ELISA) and genetic variants in the TNF-α and IL6 genes using polymerase chain reactions (PCR). The aim of this study was to screen the serum levels and genotype levels with TNF-α (C-308 T/G-308A) and IL-6 (G-174 C) genes in HBV patients and control subjects.

METHODS

In this study, we have selected 50 HBV patients and 40 control subjects from Saudi Population. Patient serum samples was used for measuring the serum levels and PCR analysis using RFLP analysis. Prior to this, HBV patients were confirmed with PCR analysis followed by Sanger sequencing analysis.

RESULTS

The current study results confirmed positive association in serum levels (p < 0.05) and negative association with both genotype and allele frequencies in TNF-α (C-308 T) and IL-6 (G-174 C) genes among HBV patients and controls (p > 0.05). Positive associations between blood levels of TNF-α and IL-6 were confirmed, while negative associations were found between PCR investigations involving the TNF-α (G-308A) and IL-6 (G-174 C) genes with the HBV prevalence in the Saudi population.

CONCLUSION

This study confirmed serum levels are strongly associated with HBV patients in the Saudi population. However, PCR studies showed the negative association with the couple of variants selected for this study.

Antigen Recognition and Immune Response to Acute and Chronic Hepatitis B Virus Infection

The antigen recognition and immune response to acute and chronic hepatitis B virus (HBV) infections are the result of both the innate and adaptive immune response. The innate immune response comprises Dendritic Cells (DCs), which served as professional antigen-presenting cells and a bridge between innate and adaptive immunity, Kupffer cells and inflammatory monocytes for the continuous inflammation of hepatocyte, neutrophils for hepatic tissue damage due to acute inflammation, type I interferons (IFN), which induce an antiviral state on infected cells, directs natural killer (NK) cells to kill virally infected cells, reduces the population of infected cells, and promotes the effective maturation and site recruitment of adaptive immunity through the production of pro-inflammatory cytokines and chemokines. Through stimulating B cells, T-helper, and cytotoxic T cells, the adaptive immune system also protects against hepatitis B infection. During HBV infection, a network of cell types that can either play protective or harmful functions creates the anti-viral adaptive immune response. These many elements, such as ‎Cluster of differentiation four (CD4) T cells (traditionally known as helper T cells), are potent cytokine producers and necessary for the effective maturation of effector cytotoxic cluster of differentiation eight (CD8) T cells and B cell antibody production. By cytolytic and non-cytolytic processes, CD8 T cells are able to eliminate HBV-infected hepatocytes and directly detect virus-infected cells, and circulating CD4+ CD25+ regulatory T cells for the modulation of immune system. In order to avoid reinfection, B cells can produce antibodies that destroy free viral particles. Moreover, by presenting HBV antigens to helper T cells, B cells may also influence how well these cells operate.

Genome-Wide Association Study for Chronic Hepatitis B Infection in the Thai Population

To identify novel host genetic variants that predispose to hepatitis B virus (HBV) persistence, we performed the first genome-wide association study in the Thai population involving 318 cases of chronic hepatitis B and 309 healthy controls after quality control measures. We detected the genome-wide significant association of the HLA class II region (HLA-DPA1/DPB1, rs7770370, p-value = 7.71 × 10⁻¹⁰, OR = 0.49) with HBV chronicity. Subsequent HLA allele imputation revealed HLA-DPA1*01:03 (Pc = 1.21 × 10⁻⁶, OR = 0.53), HLA-DPB1*02:01 (Pc = 2.17 × 10⁻³, OR = 0.50), and HLA-DQB1*06:09 (Pc = 2.17 × 10⁻², OR = 0.07) as protective alleles, and HLA-DPA1*02:02 (Pc = 6.32 × 10⁻⁵, OR = 1.63), HLA-DPB1*05:01 (Pc = 1.13 × 10⁻⁴, OR = 1.72), HLA-DPB1*13:01 (Pc = 4.68 × 10⁻², OR = 1.60), and HLA-DQB1*03:03 (Pc = 1.11 × 10⁻³, OR = 1.84) as risk alleles for HBV persistence. We also detected suggestive associations in the PLSCR1 (rs35766154), PDLIM5 (rs62321986), SGPL1 (rs144998273), and MGST1 (rs1828682) loci. Among single-nucleotide polymorphisms in the PLSCR1 locus, rs1061307 was identified as the primary functional variant by in silico/in vitro functional analysis. In addition to replicating the association of the HLA class II region, we detected novel candidate loci that provide new insights into the pathophysiology of chronic hepatitis B.

The IL6-174G/C Polymorphism Associated with High Levels of IL-6 Contributes to HCV Infection, but Is Not Related to HBV Infection, in the Amazon Region of Brazil

The dysregulation of cytokine production can lead to an inefficient immune response, promoting viral persistence that induces the progression of chronic viral hepatitis. The study investigated the association of the IL6-174G/C polymorphism with changes in cytokine levels and its influence on the persistence and progression of chronic hepatitis caused by HBV and HCV in 72 patients with chronic hepatitis B (HBV), 100 patients with hepatitis C (HCV), and a control group of 300 individuals. The genotyping of the IL6-174G/C polymorphism was performed by real-time PCR, and cytokine levels were measured by enzyme-linked immunosorbent assay (ELISA). HCV patients with the wild-type genotype (GG) had a higher viral load (p = 0.0230). The plasma levels of IL-6 were higher among patients infected with HBV and HCV than among the control group (p < 0.0001). Patients with HCV were associated with increased inflammatory activity (A2−A3; p < 0.0001). In hepatitis C, carriers of the GG genotype had higher levels of IL-6 (p = 0.0286), which were associated with A2−A3 inflammatory activity (p = 0.0097). Patients with A2−A3 inflammatory activity and GG genotype had higher levels of IL-6 than those with the GC/CC genotype (p = 0.0127). In conclusion, the wild-type genotype for the IL6-174G/C polymorphism was associated with high levels of IL-6 and HCV viral load and inflammatory activity, suggesting that this genotype may be a contributing factor to virus-induced chronic infection.

Interindividual immunogenic variants: Susceptibility to coronavirus, respiratory syncytial virus and influenza virus

The coronavirus disease (Covid-19) pandemic is the most serious event of the year 2020, causing considerable global morbidity and mortality. The goal of this review is to provide a comprehensive summary of reported associations between inter-individual immunogenic variants and disease susceptibility or symptoms caused by the coronavirus strains severe acute respiratory syndrome-associated coronavirus, severe acute respiratory syndrome-associated coronavirus-2, and two of the main respiratory viruses, respiratory syncytial virus and influenza virus. The results suggest that the genetic background of the host could affect the levels of proinflammatory and anti-inflammatory cytokines and might modulate the progression of Covid-19 in affected patients. Notably, genetic variations in innate immune components such as toll-like receptors and mannose-binding lectin 2 play critical roles in the ability of the immune system to recognize coronavirus and initiate an early immune response to clear the virus and prevent the development of severe symptoms. This review provides promising clues related to the potential benefits of using immunotherapy and immune modulation for respiratory infectious disease treatment in a personalized manner.

Coronavirus: Pure Infectious Disease or Genetic Predisposition

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes novel coronavirus disease (COVID-19), is the seventh pathogenic coronavirus recently discovered in December 2019 in Wuhan, China. To date, our knowledge about its effect on the human host remains limited. It is well known that host genetic factors account for the individual differences in the susceptibility to infectious diseases. The genetic susceptibility factors to COVID-19 and its severity are associated with several unanswered questions. However, the experience gained from an earlier strain of coronavirus, SARS-CoV-1, which shows 78% genetic similarity to SARS-CoV-2 and uses the same receptor to bind to host cells, could provide some clues. It, therefore, seems possible to assemble new evidence in order to solve a potential genetic predisposition puzzle for COVID-19. In this chapter, the puzzle pieces, including virus entry receptors, immune response, and inflammation-related genes, as well as the probable genetic predisposition models to COVID-19, are discussed.

HLA-DRB1 genes and the expression dynamics of HLA CIITA determine the susceptibility to T2DM

Type 2 diabetes mellitus (T2DM) is a disease with polygenic inheritance. The expression of major histocompatibility complex class II genes are regulated by several trans-activators. We have studied the expression of HLA-DRB1, RFX, CIITA-P1, PIV transactivators, immunophenotyping of cells, SNPs in CIITA-168 (A/G) and IFN-γ + 874 (T/A) in T2DM patients and controls (n = 201 each). We observed increased frequencies of DRB1*03, DRB1*04 and DRB1*07 and decreased frequencies of DRB1*10, DRB1*14, and DRB1*15 alleles among patients. Significant up-regulations of HLA-DRB1 genes were observed in patients (p < 0.0001). Down-regulated expressions were documented in DRB1*03-homo (p < 0.002) and DRB1*04-homo (p < 0.009) patients. No significant differences were observed for CIITA-P1 expression except DRB1*04-pooled (p < 0.0113). The CIITA-PIV was up-regulated in overall (p < 0.0001), DRB1*03-pooled (p < 0.0006), DRB1*03-hetero (p < 0.0006) and DRB1*03-homo (p < 0.001) T2DM patients. However, significant down-regulations were documented for DRB1*04-pooled (p < 0.040), DRB1*04-hetero (p < 0.060), and DRB1*04-homo (p < 0.027) combinations. Further, significant down-regulations of RFX5 were observed in overall (p < 0.0006), DRB1*04-pooled (p < 0.0022), and DRB1*04-hetero (p < 0.0004) combinations. Immunophenotyping studies revealed significant increase of CD45⁺ CD14^-, CD19⁺, CD14^- and CD8 cells and elevated level of expression of IFN-γ (p < 0.0001) in patients. A significant increase of TT (p < 3.35 × 10^-6) and decrease of TA (p < 4.57 × 10^-4) genotypes of IFN-γ + 874 (T/A) and an increase of GG (p < 0.001) and decrease of AG (p < 8.24 × 10^-5) genotypes of CIITA-168 A/G SNPs were observed. The combinatorial analysis revealed susceptible associations for DRB1*03 + AA, *03 + AG, *03 + GG and *04 + GG and protective associations for DRB1*10 + AG, *10 + GG, *15 + AG, and *14 + GG combinations. Thus, the present study corroborated the effect of differential expressions of promoters of risk alleles in the pathogenesis of T2DM.

IFNL4 rs12979860 polymorphism influences HBV DNA viral loads but not the outcome of HBV infection in Moroccan patients

OBJECTIVES

The interferon (IFN) is known to bridge innate and adaptive immune responses, and to play a critical role particularly against hepatitis B virus (HBV) infection. Defects in IFN signals may result, therefore, in attenuated responses against HBV. Accordingly, polymorphisms in genes coding for immune response effectors may affect the clinical outcome of HBV infection. We analyzed the putative association between IFNL4 rs12979860 polymorphism and the outcome of HBV infection in Moroccan patients.

METHODS

In this study, 237 chronic HBV (CHB) patients and 129 spontaneously resolved HBV (SRB) individuals were enrolled and genotyped using a predesigned Taqman allelic discrimination assay.

RESULTS

Our data show a significant increase of HBV DNA loads in patients with IFNL4 rs12979860 CC genotype compared to patients with CT and TT genotypes (p = 0.0008). However, there was no consistent association between IFNL4 rs12979860 polymorphism and the outcome of HBV infection.

CONCLUSIONS

Although IFNL4 rs12979860 polymorphism seems to modulate circulating HBV DNA levels, it is disconnected from chronic disease progression. This observation suggests that the role of rs12979860 in liver disease is restricted to viral control and inactive in the deleterious immune pathology that affects liver tissue. Taken together, our data suggest that rs12979860 CC genotypes could be useful as a predictor of success or failure of IFN-based therapy in chronic HBV-infected patients.

Association of interleukin-6 gene polymorphisms with the risk of hepatocellular carcinoma: An up-to-date meta-analysis

BACKGROUND

This study was aimed to evaluate the association between interleukin-6 (IL-6) gene polymorphisms and the risk of hepatocellular carcinoma (HCC) in a meta-analysis.

METHODS

A literature search was performed for case-control studies published during May, 1993 to May, 2020 focusing on IL-6 gene polymorphisms (-174G > C, -572G > C, and -597G > A) and HCC susceptibility by using PubMed, Cochrane Database, EMBASE, Web of science, and China National Knowledge Infrastructure. From 128 full-text articles, 11 were included in this meta-analysis. I index was used to assess heterogeneity and Newcastle-Ottawa Scale was utilized for quality assessment.

RESULTS

For IL-6 -174G > C polymorphism, in codominant (GG vs CC: odds ratios [OR] = 2.78, 95% confidence intervals [CI] = 1.25-6.19, P = .01, I = 16%) and recessive (GG+GC vs CC: OR = 2.76, 95% CI = 1.29-5.90, P = .009, I = 3%) models, IL-6 -174G>C polymorphism was significantly associated with the risk of HCC. In dominant (GG vs CC+GC: OR = 1.80, 95% CI = 0.92-3.54, P = .09, I = 86%) and allele (G vs C: OR = 1.49, 95% CI = 0.95-2.32, P = .08, I = 68%) models, IL-6 -174G>C polymorphism had no impact on the risk of HCC. However, in non-Italian Caucasian population, IL-6 -174G>C polymorphism was significantly related to the occurrence of HCC in both dominant (GG vs CC+GC: OR = 3.26, 95% CI = 2.29-4.65, P < .00001, I = 0%) and allele (G vs C: OR = 2.48, 95% CI = 1.48-4.15, P = .0006) models. Such correlations also could be observed when healthy individuals were selected as controls. For IL-6 -572G>C and -597G>A polymorphisms, no significant association was observed in all models, regardless of the source of control and population subgroups. No publication bias could be calculated when Begg and Egger tests were employed.

CONCLUSION

This meta-analysis indicated that IL-6 -174G>C polymorphism was significantly related with the risk for HCC, especially in non-Italian Caucasian population. No significant association was observed for the correlation between IL-6 -572G>C and -597G>A polymorphisms and HCC susceptibility.

Genetic Association of Interleukin-6 Polymorphism (rs1800796) with Chronic Hepatitis B Virus Infection in Chinese Han Population

Hepatitis B virus (HBV) infection is a global health care burden that can lead to chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. We conducted this study to identify the association between interleukin-6 (IL-6) gene rs1800796 (-572G/C) polymorphism and the risk of chronic HBV infection in adults. A total of 1,048 participants including 518 cases and 530 controls were recruited for this study. The Mass Array time-of-flight mass spectrometer was applied for single-nucleotide polymorphism rs1800796 genotyping. There was a significant correlation between genotype CG in rs1800796 and chronic HBV infection in the Chinese Han population (odds ratio [OR] = 0.759, 95% confidence interval [CI]: 0.586-0.983, p = 0.04), which was also observed at allele G (OR = 0.800, 95% CI: 0.657-0.975, p = 0.02). Furthermore, significant differences in the ≤45 years old group (CC vs. CG+GG, OR = 0.616, 95% CI: 0.413-0.918, p = 0.02) and in the male group (CC vs. CG+GG, OR = 0.666, 95% CI: 0.483-0.920, p = 0.01) were found in the subgroups analysis. Our data revealed a significant association of IL-6 rs1800796 with the risk of chronic HBV infection in the Chinese Han population; meanwhile, age and gender are two coordinative risk factors, which provides new clues for the study of susceptibility of chronic HBV infection in adults.

Interferon gamma gene polymorphisms and chronic hepatitis B infections in an Iranian population

BACKGROUND AND AIMS

Chronic hepatitis B is an important health problem in all countries. I Interferon gamma is a pro-inflammatory Th1 cytokines, which can exert antiproliferative and antitumor activity. Some SNPs in IFN-γ and IFN-γR1 genes may influence the susceptibility to HBV. Here, we evaluated the impact of interferon gamma (+874 T/A) and its receptor (-611A/G, +189G/C and +95C/T) polymorphisms and the risk of HBV in Iranian patients.

MATERIALS AND METHODS

SNPs of interferon gamma and its receptor genotypes were determined in 221 infected patients with HBV and 200 people without HBV using ARMS-PCR and PCR- RFLP method.

RESULTS

In this study, we showed an obvious relationship between IFN-γ SNPs and susceptibility to chronic HBV. Our findings suggest that IFN-γ-874A allele increases the risk of disease and carriers of the T allele have reduced susceptibility to infection. In addition, there was not any relationship between the -611A/G, +189G/C and +95C/T regions of IFN-γ R1 and HBV.

CONCLUSIONS

Our observations demonstrate +874 T/A SNP as a predicting factor in patients who have the risk of HBV.

Interleukin IL-1B gene polymorphism in Tunisian patients with chronic hepatitis B infection: Association with replication levels

Approaches based on association studies have proven useful in identifying genetic predictors for many diseases, including susceptibility to chronic hepatitis B. In this study we were interested by the IL-1B genetic variants that have been involved in the immune response and we analyzed their role in the susceptibility to develop chronic hepatitis B in the Tunisian population. IL-1B is a potent proinflammatory cytokine that plays an important role in inflammation of the liver. Polymorphic gene IL-1 (-511, +3954) was analyzed in a total of 476 individuals: 236 patients with chronic hepatitis B from different cities of Tunisia recruited in Pasteur Institute between January 2017 and December 2018 and 240 controls. Genomic DNA was obtained using the standard salting-out method and genotyping was performed by polymerase chain reaction (PCR)-restriction fragment length polymorphism. For -511C>T polymorphism a significant association was found between patients and controls when comparing the genotypic (P = 0.007; χ²  = 9.74 and odds ratio [OR] = 0.60; confidence interval [CI] = 0.41-0.89) and allelic (P = 0.001; χ²  = 10.60) frequencies. When the viral load was taken into account a highly significant difference was found (P = 9 × 10^-4 ; χ²  = 10.89). For +3954C>T polymorphism a significant association was found between patients and controls when comparing genotypic (P = 0.0058; χ²  = 7.60 and OR = 1.67; CI = 1.14-2.46) and allelic (P = 0.0029; χ²  = 8.81) frequencies. T allele can be used as a strong marker for hepatitis B virus disease for both polymorphisms.

Single Nucleotide Polymorphisms in IFN-γ Signaling Pathway Associated with Risk of Hepatitis B Virus Infection in Chinese Children

Hepatitis B virus (HBV) infection is a challenging public health problem in China and worldwide. Mother-to-child transmission is one of the main transmission routes of HBV in highly endemic regions. However, the mechanisms of HBV perinatal transmission in children have not been clearly defined. The aim of this study was to demonstrate the association between single-nucleotide polymorphisms (SNPs) in IFN-γ signaling pathway and HBV infection or breakthrough infection in children. Two hundred and seventy-four HBV-infected children defined as test positive for hepatitis B surface antigen (HBsAg) and 353 controls defined as negative for HBsAg in China were recruited from October 2013 to May 2015. SNPs in IFN-γ signaling pathway including IFNG, IFNGR1, IFNGR2, and IL12B were genotyped. Rs2234711 in IFNGR1 was significantly associated with HBV infection in children (OR = 0.641, 95% CI: 0.450–0.913). In addition, rs2234711 was also significantly associated with HBV breakthrough infection in children born to HBsAg-positive mothers (OR = 0.452, 95% CI: 0.205–0.998). Our study confirmed that genetic variants in IFN-γ signaling pathway have significant associations with HBV infection, especially with HBV breakthrough in children. This study provides insight into HBV infection in children and could be used to help design effective strategies for reducing immunoprophylaxis failure.

Assessment of HLADP gene rs3128917 and rs9380343 polymorphisms in chronic HBV infection

BACKGROUND/AIMS

About 400 million people worldwide have been exposed to Hepatitis B (HBV) infection. A range of 10%-15% of chronic HBV carriers may present with various liver diseases including cirrhosis and hepatic cancer. The chronicity or clearance of HBV infection is dependent on viral and genetic variables. Genome-wide association studies (GWAS) have reported that the variants of human leukocyte antigen (HLA), rs3128917 and rs9380343, are significantly related to persistent HBV infection. HLA molecules are responsible for introducing various antigens into the immune system. These variants might affect antigen presentation by influencing HLA mRNA expression, therefore, antigen presentation may not be performed properly. This study aims to assess the relationship of HLA gene variants to chronic HBV infection.

MATERIALS AND METHODS

HLA variants were explored in 238 chronic HBV patients and in 238 individuals with spontaneous clearance of HBV using PCR-RFLP assay.

RESULTS

The allele and genotype of rs9380343 polymorphism were associated with persistent HBV infection risk (allele: p=0.038, genotype: p=0.029), but rs3128917 polymorphism was not significant. Additionally, rs9380343 polymorphism was also related to increased risk of HBV infection in males (p<0.05).

CONCLUSION

The current study is the first report demonstrating the HLA rs9380343 polymorphism as a genetic risk factor for chronicity of HBV infection. Further independent studies are required to confirm the current findings using a larger sample size in different populations.

Racial Differences in Immunological Landscape Modifiers Contributing to Disparity in Prostate Cancer

Prostate cancer affects African Americans disproportionately by exhibiting greater incidence, rapid disease progression, and higher mortality when compared to their Caucasian counterparts. Additionally, standard treatment interventions do not achieve similar outcome in African Americans compared to Caucasian Americans, indicating differences in host factors contributing to racial disparity. African Americans have allelic variants and hyper-expression of genes that often lead to an immunosuppressive tumor microenvironment, possibly contributing to more aggressive tumors and poorer disease and therapeutic outcomes than Caucasians. In this review, we have discussed race-specific differences in external factors impacting internal milieu, which modify immunological topography as well as contribute to disparity in prostate cancer.

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.

Influence of genetic variants of gamma interferon, interleukins 10 and 12 on Visceral Leishmaniasis in an endemic area, Iran

Visceral leishmaniasis (VL) is a life threatening disease in which a variety of cytokines regulating the immune responses can determine its outcome. As based on their region in the gene, some single nucleotide polymorphisms (SNP) can influence the expression of their corresponding proteins, this study aimed to investigate the association between SNP in the IL-10, IL-12, IFN-γ genes and susceptibility to VL. The study was carried out on 120 patients with VL, 67 patients' families (family group), and 102 healthy individuals with positive leishmanin skin test as positive control group. SNPs in IL-10 (-592, -819, -1082), IL-12 (+1188) were analyzed using PCR-RFLP and allele specific polymerase chain reaction (ASPCR) was used to analyze SNPs in IFN-γ (+874 A/T). The results showed that at position +874 of IFN-γ, AT genotype was significantly more frequent in patients than that in families and controls, but TT genotype was significantly more frequent in families than in patients. Distributions of IFN-γ alleles were not significantly different between the study groups. As for IL-12 and IL-10 genotypes and alleles, no significant difference was observed between the groups. Although a strong linkage disequilibrium was observed between alleles -592, -819 and -1082 of IL-10, distributions of the most common haplotypes and haplogenotypes reconstructed from IL-10 alleles were not significantly different between the study groups. It could be suggested that heritage of AT genotype at position +874 of IFN-γ may predispose and TT genotype can resist individual to VL in an endemic area in the southwest of Iran.

Association between Interleukin-21 and Interleukin-21 receptor gene polymorphisms with susceptibility to chronic hepatitis B virus infection and HBV spontaneous clearance in Iranian population

Hepatitis B virus (HBV) infection is a major public health concern due to the infection often leads to chronic infection, liver cirrhosis and also liver cancer. The host immune response to HBV infection and also genetic background play significant role in outcome of infection. Single nucleotide polymorphisms (SNPs) are the most important kind of variation in genetic sequences that caused by point mutations. As cytokines have major roles in viral infections, it seems that cytokine gene polymorphisms are independently associated with response to viral infections. Interleukin 21 (IL-21) plays an influential role in both innate and adaptive immune responses. Its specific receptor, IL-21R, produced and located on the surface of T, B and natural killer (NK) cells and is critical for the proliferation and differentiation of these immune effector cells. Many studies confirmed that the IL-21 involved in response to viral infections. We aimed to investigate the association of G/T IL-21 (rs2055979) and C/T IL-21R (rs3093390) gene polymorphisms with chronic hepatitis B virus infection and HBV spontaneous clearance in Iranian population.

METHODS

In this study, blood samples were gathered from 320 patients with chronic HBV and 310 healthy controls and also 120 HBV spontaneous clearance individuals. Following genomic DNA extraction, genotypes of the selected SNPs determined by PCR and restriction fragment length polymorphism (RFLP) method. The results were analyzed by SPSS software using Chi-square, Logistic Regression, ANOVA and Independent Samples t-Test.

RESULTS

According to our results, in IL-21R (rs3093390 C/T) gene polymorphism, allele frequency of T is statistically different in the HBV spontaneous clearance group compared to chronic HBV cases. But there is no significant difference between G/T IL-21 (rs2055979) and C/T IL-21R (rs3093390) genotypes distribution in three groups. Also we found that higher serum aspartate transaminase (AST) level in HBV spontaneous clearance group is significantly associated with TT genotype of IL-21 (rs2055979) compared to GG genotype (P value = 0.006).

DISCUSSION

Our results showed that T allele frequency in IL-21R (rs3093390 C/T) gene polymorphism could consider as a host genetic factor for HBV spontaneous clearance. Probably we can serve it as a potential prognostic genetic marker for spontaneous clearance of HBV infection.

Interferon-γ receptor-1 gene promoter polymorphisms and susceptibility for brucellosis in Makkah region

BACKGROUND

Genetic polymorphisms that affect the production levels of certain cytokines and/or their receptors may determine the risk, severity or protection in some infectious diseases like brucellosis.

OBJECTIVES

The aim of this study was to investigate the association of certain known Interferon-γ Receptor-1 (IFN-γ R1) gene promoter polymorphisms and the susceptibility to infection with Brucellosis in Saudi population.

METHODS

A cases-control association study was conducted in 69 individuals with human brucellosis and 94 healthy individuals. Genotyping of IFN-γ R1 - 56 C>T and IFN-γ R1 - 611 A>G polymorphism in both patients and healthy controls was done by PCR- restriction enzyme length polymorphisms (PCR-RFLP) and PCR- confronting two primer pairs (PCR-CTPP) methods and were assessed for potential associations with susceptibility for human brucellosis and their mode of penetrance.

RESULTS

Interestingly, we have designed a PCR-CTPP system to be used for genotyping of IFN-γ R1 - 611 A > G polymorphism. The PCR-CTPP is an accurate method for genotyping of SNPs. Moreover, it is time-saving, inexpensive and easy to perform.

CONCLUSION

Both tested polymorphisms, IFN-γ R1 - 56 C>T and IFN-γ R1 -611 A>G polymorphism had no role in genetic susceptibility to human brucellosis in the study population. The PCR-CTPP can be used for genotyping IFN-γ R1 - 611 A > G polymorphism and other types of mutation.

CD56bright natural killer cells induce HBsAg reduction via cytolysis and cccDNA decay in long-term entecavir-treated patients switching to peginterferon alfa-2a

HBV surface antigen (HBsAg) reduction is well observed in chronic hepatitis B (CHB) patients treated with pegylated interferon alpha-2a (PegIFNα). However, the mechanism of HBsAg suppression has not been fully elucidated. Twenty-seven of 55 entecavir-treated CHB e antigen positive patients were switched to PegIFNα treatment (Group A) whereas 28 patients continued entecavir treatment (Group B). The percentage or absolute number of CD56^bright /CD56^dim NK cells, expression of receptors and cytokines were evaluated by flow cytometry for 48 weeks and correlated with treatment efficacy. In vitro, purified NK cells were co-cultured with HepAD38 cells for measurement of HBsAg, apoptosis and covalently closed circular DNA (cccDNA). In association with a reduction of HBsAg, the percentage and absolute number of CD56^bright NK cells was significantly elevated in patients in group A, especially in Virologic Responders (VRs, HBsAg decreased). Furthermore, the percentage of NKp30⁺ , NKp46⁺ , TRAIL⁺ , TNF-α⁺ and IFNγ⁺ CD56^bright NK cells were significantly expanded in Group A, which were positively correlated with the decline of HBsAg at week 48. In vitro, peripheral NK cells from Group A induced a decline of HBsAg in comparison with NK cells from Group B which was significantly inhibited by anti-TRAIL, anti-TNF-α and anti-IFNγ antibodies. Furthermore, apoptosis of HepAD38 cells and levels of cccDNA, were significantly reduced by TRAIL⁺ and TNF-α⁺ /IFNγ⁺ NK cells from Group A, respectively. A functional restoration of CD56^bright NK cells in entecavir-treated patients who were switched to PegIFNα contributes to HBsAg and cccDNA clearance through TRAIL-induced cytolysis and TNF-α/IFNγ-mediated noncytolytic pathways.

Systematic Review and Meta-Analysis on the Association between Polymorphisms in Genes of IL-12 Signaling Pathway and Hepatocellular Carcinoma Risk

We performed an updated meta-analysis and systematic review to explore the associations between polymorphisms in genes of IL-12 signaling pathway and hepatocellular carcinoma (HCC) risk. Diverse databases were retrieved to identify entire available studies, and odds ratios (ORs) correspondence with 95% confidence intervals (CIs) were performed to assess their associations. Finally, 6 polymorphisms in five genes of the IL-12 signaling pathway were extracted from 39 case-control studies, 26 publications. We identified that STAT4-rs7574865 polymorphism was significantly associated with an increased risk of HCC in allelic contrast, dominant, homozygote and recessive models. However, we failed to uncover any significant association between other polymorphisms in genes of IL-12 signaling pathway and HCC risk, including IL18-rs1946518 and -rs187238, IFN-γ-rs2430561, IL12A-rs568408, IL12B-rs3212227 and STAT4-rs7574865. When the subgroup analysis was conducted based on Hardy-Weinberg Equilibrium (HWE) status, we identified that IFN-γ-rs2430561 polymorphism was significantly associated with an increased risk of HCC in homozygote and recessive models of these studies whose control groups were conformed to HWE. To sum up, our study suggests that STAT4-rs7574865 is a risk factor for HCC. Further well-designed large sample size studies are warranted to shed new light on these findings.

Associations of human leukocyte antigen and interleukin-18 gene polymorphisms with viral load in patients with hepatitis B infection

This study aimed to assess the associations of human leukocyte antigen (HLA)-DR and interleukin (IL)-18 gene polymorphisms with hepatitis B virus (HBV).Clinical data were retrospectively reviewed between December 2006 and December 2015 at Xiangyang Central Hospital. HBV patients were assigned to the high and low viral load groups, respectively, according to HBV copies. HLA-DRB1*03 polymorphisms and IL-18 polymorphisms were detected by sequence-specific primer-polymerase chain reaction (PCR-SSP) and PCR-ligase detection reaction (PCR-LDR), respectively. T cell subgroups were identified by flow cytometry, and IL-18, IL-12, interferon-γ (IFN-γ), IL-4, and IL-10 expression levels were assessed by ELISA. A total of 630 subjects were included in the analysis.Compared with healthy controls, the chronic HBV group showed significantly lower IL-18 (P < .001), IL-12 (P < .001), and IFN-γ (P < .001) expression levels, and markedly increased IL-4 (P < .001) and IL-10 (P < .001) amounts. Th2 cytokine expression was high in HLA-DRB1*03 positive (+) HBV patients, with low Th1 cytokine levels. The ratios of CD4+/CD8+ and Th1/Th2 cells decreased with increasing HBV DNA levels. The chronic HBV group showed a relatively high frequency of -137G in the IL-18 gene, while IL-18 expression was low in homozygous GG genotype individuals.Polymorphisms in the HLA-DRB1*03 and IL-18 genes are associated with viral load in HBV. HLA-DRB1 and IL-18 gene polymorphisms are involved in the regulation of the Th1/Th2 balance and expression of relevant cytokines that influence immune responses in HBV.

Role of Functional IFNL4, IFNLR1, IFNA, IFNAR2 Polymorphisms in Hepatitis B virus-related liver disease in Han Chinese population

Recent studies show that variants in some interferon genes together with interferon receptor genes are associated with the outcome of infectious diseases. We examined the association between the risk of hepatitis B virus (HBV)-related liver disease and the functional polymorphisms within IFNL4, IFNLR1, IFNA1, IFNA2, IFNA5 and IFNAR2 genes (14 loci in all) in a Han Chinese population. A total of 3128 people participated and were divided into 5 groups: healthy controls, natural clearance, chronic hepatitis B(CHB), liver cirrhosis and hepatocellular carcinoma (HCC). Significant associations were observed for 4 variants in IFNAR2, IFNLR1 with HBV infection, and IFNLR1-rs4649203 was associated with HBV recovery. Moreover, we demonstrated the clear relevance of 5 polymorphisms in IFNA1, IFNA2, IFNL4 with HCC. Three SNPs in IFNL4 gene may be important susceptible factors for the progression of HBV-related liver disease by trend chi-square test. The IFNL4 haplotype conformed by rs12971396_G, rs8113007_T and rs7248668A was more frequent in HCC than CHB and LC group. Three polymorphisms in the 5' region of the IFNL4 gene are associated with the progression of HBV-related liver disease. IFNA1- rs1831583 and IFNA2- rs649053 are associated with the development of HCC. IFNLR1- rs4649203, rs7525481 are predictors for HBV infection, and rs4649203 is a predictor of spontaneous clearance. IFNAR2 -rs1051393, rs12233338 may be predictive markers of HBV infection in the Chinese population.

Impact of cellular restriction gene (TRIM5α, BST-2) polymorphisms on the acquisition of HIV-1 and disease progression

BACKGROUND

TRIM5α and BST-2 are cellular restriction factors affecting the HIV-1 infection and its progression. Genetic variability in these genes alters the expression pattern. Hence, we aimed to examine the impact of the TRIM5α (rs10838525, rs7127617 and rs904375) and BST2 (rs3217318 and rs71694748) polymorphisms on the acquisition of HIV-1 and its progression.

METHODS

Genotyping of TRIM5α and BST-2 polymorphisms was performed in a total of 153 HIV-infected patients and 158 unrelated healthy individuals using a polymerase chain reaction-restriction fragment length polymorphism method.

RESULTS

No significant differences were found in the genotype frequencies of TRIM5α polymorphisms between HIV patients and healthy controls. BST-2 Δ19/i19 and i19/i19+ Δ19/i19 genotypes appeared more frequently in HIV patients compared to healthy controls (10.4% versus 7.0%, p = 0.20; 11.10% versus 7.6%, p = 0.16). The BST-2 i19 allele was associated with the acquisition of HIV-1 [odds ratio (OR) = 2.76, p = 0.030)]. TRIM5α haplotypes ATG and ACA elevated the risk, whereas haplotype ATA reduced the risk for the acquisition of HIV-1 (OR = 1.92, p = 0.026; OR = 4.88, p = 0.016; OR = 0.31, p = 0.014). BST-2 Δ19/i19 and i19/i19+ Δ19/i19 genotypes were more prevalent in patients with early HIV disease stage compared to healthy controls (15.9% versus 7.0%, p = 0.096; 15.9% versus 7.6%, p = 0.12). The prevalence of TRIM5α rs7127617 CC and BST-2 Δ19/i19 genotypes was observed to be higher in alcohol-using HIV patients compared to non-users (27.8% versus 20.0%, p = 0.35, 22.2% versus 10.0%, p = 0.24).

CONCLUSIONS

TRIM5α haplotypes and the BST-2 i19 allele may significantly affect the modulation of HIV-1 acquisition and its progression. TRIM5α rs7127617 CC and BST-2 Δ19/i19 genotypes in alcohol-using HIV patients elevated the risk of HIV disease progression.

Human leukocyte antigen A, B and Hepatitis B infection outcome: A meta-analysis

AIM

To evaluate the association between HLA A, B with chronic Hepatitis B by comprehensive meta-analysis.

METHODS

We searched PubMed and Cochrane databases, identified relevant studies, evaluated these for quality by New Castle Ottawa scale (NOS) and further analyzed the qualified data sets. Heterogeneity analyses were performed by Cochrane's Q test and I² tests. Pooled Odds ratio (OR) & 95% Confidence Interval (CI) were obtained by fixed effects, using Mantel-Haenszel's method for homogenous studies, and by using DerSimonian and Laird's method for heterogenous studies. Publication bias was determined by the Beggs test and Eggers test and all tests were two tailed to evaluate their significance.

RESULTS

The meta-analyses on 1652 healthy controls and 659 Chronic Hepatitis B (CHB) patients from 8 studies from various continents revealed a HLA B*07 (p value of Odds ratio (pOR)=0.004; OR Fixed effects=0.480 with 95%CI 0.290-0.794) and B*58 (pOR=0.029; OR Fixed Effects=0.020 with 95%CI 0.381-0.949) associated protection for CHB. The identified HLA B*35 associated risk (pOR 0.009; OR Fixed effect 1.445; 95% confidence interval 1.094-1.907) however did not stand the test of random effect model.

CONCLUSION

While HLA B*07 and B*58 are protective against CHB. The HLA B*35 associated marginal risk need to be further validated in well-designed global study on larger cohorts, considering the population, ethnic, epidemiological and HLA diversity at the sequence level: these may throw further light to utilize these markers in predictive medicine.

Three polymorphisms of tumor necrosis factor-alpha and hepatitis B virus related hepatocellular carcinoma: A meta-analysis

BACKGROUND

To assess the association between tumor necrosis factor-alpha (TNF-α) G308A, G238A and C863T polymorphisms and hepatitis B virus related hepatocellular carcinoma (HBV-HCC) susceptibility.

METHODS

We interrogated the databases of Pubmed, Sciencedirect and Viley online library up to March 8, 2016. Odds ratios (ORs) and corresponding 95% confidence intervals (95%CIs) were calculated in a fixed-effects model or a random-effects model when appropriate.

RESULTS

In total, 12 case-control studies which containing 1580 HBV-HCC cases, 2033 HBV carrier controls, 395 HBV spontaneously recovered (SR) controls and 1116 healthy controls were included. Compared with GG genotype, the genotypes GA/AA of G308A were associated with a significantly increased HBV-HCC risk when the controls were all healthy individuals (AA vs. GG, OR 2.483, 95%CI 1.243 to 4.959; GA vs. GG, OR 1.383, 95%CI 1.028 to 1.860; GA/AA vs. GG, OR 1.381, 95%CI 1.048 to 1.820). Meanwhile, only the AA vs. GG model of G238A and HBV-HCC showed a statistic significance when the controls were healthy individuals (OR 4.776, 95%CI 1.280 to 17.819). CT genotype of TNF-α C863T could increase HBV-HCC risk whenever the controls were healthy individuals, HBV carriers or HBV recovers.

CONCLUSION

This meta-analysis shows that AA genotype in TNF-α G308A and TNF-α G238A and CT genotype in TNF-α C863T may increase HBV-HCC risk. Therefore, HBV infection seemed to be a more important factor for tumorigenesis of HCC than genetic predisposition in G308A of TNF-α, and interaction between TNF-α C863T polymorphisms and HBV infection might be associated with increased HCC risk.

Interferon Gamma Gene Polymorphism (+874 T > A) and Chronic Hepatitis B in the Population of Gorgan, North-Eastern Iran

Background

Based on differences in individual immune responses to the hepatitis B virus (HBV), between 5% and 10% of patients become persistently infected with the virus, which leads to the determination of chronic HBV. Cytokines such as interferon gamma (IFN-γ) are secretory proteins that play important roles in both innate and adaptive immune responses. Functional studies have demonstrated that the IFN + 874A/T gene polymorphism can increase or decrease the overall expression of IFN-gamma (γ) and ultimately determine the outcome of the infection.

Objectives

This study was performed to investigate the relationship between the IFN-γ + 874 gene polymorphism and susceptibility to chronic HBV infection.

Methods

Polymorphism detection analysis was performed on 598 subjects from North-Eastern Iran. The IFN-γ gene polymorphism (+ 874A/T) was genotyped through a specific sequence primer polymerase chain reaction (SSP-PCR).

Results

The frequencies of the AA, AT, and TT genotypes were 31%, 51%, and 18% in the chronic HBV patient group, and 40%, 45%, and 15% in the healthy control group, respectively. However, a lack of association of the + 874 polymorphism in the IFN-γ gene of those with chronic HBV infection was found. Evaluation of HBV association with this polymorphism was significant under the dominant genetic model (P = 0.04).

Conclusions

Ultimately, no association could be characterized between the polymorphism in IFN-γ + 874A/T and susceptibility to chronic HBV infection in this segment of the Iranian population (P > 0.05).

Association of genetic polymorphisms in interferon-γ, interleukin-6 and transforming growth factor-β1 gene with oral lichen planus susceptibility

BACKGROUND

Oral lichen planus (OLP) is a premalignant mucocutaneous disease in which genetic factors and immune responses play a major role. Cytokines play an important role in the pathogenesis and disease progression of OLP. The aim of this study was to investigate the impact of gene polymorphisms of T helper cell subtype Th1 and Th2 cytokines, interferon-gamma (IFN-γ), interleukin-6 (IL-6) and transforming growth factor (TGF)-β1 on OLP susceptibility in a Saudi cohort.

METHODS

Forty two unrelated patients with OLP and 195 healthy controls were genotyped for IFN-γ (874A/T), IL-6 (174G/C) and TGF-β1 (509C/T) polymorphisms.

RESULTS

The frequency of genotype AT of IFN-γ (874A/T) was significantly higher while genotype AA was lower in OLP patients as compared to controls (P < 0.05). The frequency of T containing genotypes (AT + TT) was also higher in OLP patients as compared to that in controls (P = 0.003). The frequencies of allele T was higher while that of allele A lower in patients than the controls however the difference was not statistically significant (P = 0.07). There was no significant difference in the frequencies of alleles and genotypes of IL-6 (174G/C) and TGF-β1 (509C/T) polymorphisms between patient and control groups. These results indicated that genotype AT of IFN-γ (874A/T) polymorphism is associated with OLP risk and genotype AA is protective to OLP. On the other hand the polymorphisms IL-6 (174G/C) and TGF-β1 (509C/T) may not be associated with OLP risk in our population.

CONCLUSION

It is concluded that IFN-γ (874A/T) polymorphism is associated with the susceptibility of OLP, however further studies with large sample size involving different ethnic populations should be conducted to strengthen our results.

APOBEC3B deletion impacts on susceptibility to acquire HIV-1 and its advancement among individuals in western India

APOBEC3B deletion polymorphism has been associated with risk of HIV-1 acquisition and its progression. Therefore, we aimed to investigate the association of APOBEC3B ins/del polymorphism with risk of acquisition of HIV-1 and its progression. In the present case-control study, we enrolled a total of 150 HIV-infected individuals and 150 healthy controls. Polymorphism for APOBEC3B gene was genotyped by PCR. APOBEC3B ID, DD genotypes, and D allele were associated with higher risk of acquisition of HIV-1 (p = 0.004, OR = 4.96; p = 0.03, OR = 3.55; and p = 0.004; OR = 1.60). The individuals with ID genotypes and combined genotype ID+DD of APOBEC3B in the presence of tobacco and alcohol showed the higher risk of advancement of HIV disease; however, risk could not reach statistical significance (OR = 1.14, 95% CI: 0.59-2.18; OR = 1.33, 95% CI: 0.83-2.15 and OR = 1.44, 95% CI: 0.77-2.69; OR = 1.50, 95% CI: 0.94-2.40). Individuals in advanced HIV disease stage and ID genotype and combined genotype ID + DD of APOBEC3B were more likely to be associated with advanced HIV disease stage but risk could not reach significant (OR = 1.50, 95% CI: 0.94-2.40; OR = 1.27, 95% CI: 0.88-1.84). Individuals with ID and DD genotype of APOBEC3B had influence on susceptibility to acquisition of HIV-1. This suggests that APOBEC3B deletion may attenuate innate cellular immunity against HIV-1 and thus confer the host persistence for HIV infection.

An HBV-tolerant immunocompetent model that effectively simulates chronic hepatitis B virus infection in mice

Hepatitis B virus (HBV) is the leading cause of liver disease and hepatic carcinoma (HCC). Approximately 350 million people worldwide are infected with HBV and at risk of chronicity. An efficient HBV-tolerant murine model that mimics HBV infection in humans is desirable for HBV-related research. In this study, we investigated and established a murine model by hydrodynamic injection (HDI) of pAAV/HBV into the tail vein of AAVS1 site element-transgenic mice. In 80% of the injected mice, the serum level of HBsAg reached 10^3-4 IU/ml and persisted for more than half a year. Next, the model was used to evaluate RNA interference (RNAi)-based antiviral therapy. Data obtained using the model demonstrated that this model will facilitate the elucidation of the mechanisms underlying chronic HBV infection and will also be useful for evaluating new antiviral drugs.

Association of IL-10 polymorphisms with hepatitis B virus infection and outcome in Han population

BACKGROUND

This study evaluated the correlation of single nucleotide polymorphisms interleukin (IL)-10-592 and -1082 with hepatitis B virus (HBV) susceptibility and recovery.

METHODS

Total 190 chronic hepatitis B (CHB) patients, 81 individuals with self-limited HBV infections and 81 normal controls from the first Hospital of Jilin University were recruited. The IL-10 polymorphisms were detected by polymerase chain reaction with restriction fragment length polymorphism (PCR-RFLP). The χ (2) test (p < 0.05) and Fisher's exact test were separately performed to analyze and compare the genotype frequencies of IL-10-592 and -1082 among different groups. Furthermore, logistic regression analysis (p < 0.05) was conducted to determine the correlation of genotypes with HBV infection and recovery. Genotype A/A, A/C and C/C of IL-10-592 had been detected in the three groups.

RESULTS

The frequencies of -592A separately were 55.56, 64.67 and 55.33 % in the three groups. Genotypes of IL-10-592 only had significant difference among the patients and normal controls (p = 0.021). Genotypes A/A, A/G and G/G of IL-10-1082 were detected in CHB patients and individuals with self-limited HBV infection; however, genotype G/G had not been detected in normal controls. The frequencies of -1082G separately were 3.68, 6.17 and 11.11 % in the three groups. Genotypes of IL-10-1082 only had no significant difference among the patients and individuals with self-limited HBV infections (p = 0.130). We found that their risks of HBV infection existed significant difference.

CONCLUSION

The IL-10-592 and -1082 polymorphisms might be associated with HBV infection, but not with the recovery after HBV infection.

Association of IL-17A and IL-17F gene polymorphisms with chronic hepatitis B and hepatitis B virus-related liver cirrhosis in a Chinese population: A case-control study

BACKGROUND

Interleukin (IL)-17 has been shown to play an important role in tissue inflammation and in the pathogenesis of immune-related liver damage. Genetic variations in IL-17 gene may be associated with the development of hepatitis B virus (HBV) infection. However, literature is scanty regarding their association.

METHODS

We conducted a case-control study including 433 subjects (171 healthy controls, 130 patients with chronic hepatitis B [CHB]; and 132 patients with HBV-related liver cirrhosis [HBV-LC] to assess the association between IL-17A rs4711998, IL-17A rs2275913 and IL-17F rs763780 polymorphisms and risk of CHB and HBV-LC. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing.

RESULTS

Our results revealed a statistically significant association between IL-17A rs4711998 G allele and increased risk of HBV-LC risk (OR=1.541, 95% CI 1.057-2.246, P=0.025). Subjects carrying the IL-17A rs4711998 AG genotype were 1.75 times more likely to develop HBV-LC (OR=1.757, 95% CI 1.096-2.817, P=0.026). Stratification analysis indicated that IL-17A rs4711998 G allele and AG genotype enhanced the risk of HBV-LC development among men and older age (≥50years) subject groups. In addition, we found that GCT haplotype also might be a risk factor for HBV-LC (OR=2.448, 95% CI 1.137-5.271, P=0.019). Furthermore, no significant association between IL-17A rs2275913 and IL-17F rs763780 polymorphisms and CHB, HBV-LC risk was observed (P>0.05).

CONCLUSION

Our data provide the first evidence that the IL-17A rs4711998 genetic variant may contribute to HBV-LC susceptibility in a Chinese population.

Genetic polymorphism of HLA-DQ confers susceptibility to hepatitis B virus-related hepatocellular carcinoma: a case-control study in Han population in China

Several recent genome-wide studies showed that the genetic polymorphisms in the HLA-DQ region (rs9275572 and rs2856718) were related to chronic hepatitis B virus (HBV) infection and chronic hepatitis C virus (HCV)-associated hepatocellular carcinoma (HCC). We analyzed the two single-nucleotide polymorphisms for major HBV outcomes in Han Chinese. A total of 1291 samples were involved and peripheral blood samples were collected in this study. Matrix-assisted laser desorption/ionization time of flight mass spectrometry were used to genotype the single-nucleotide polymorphisms in the HLA-DQ region. Our study indicated the clear relationship between the HLA-DQ rs9275572 and HBV-related HCC after control for the effects of sex, drinking, and smoking. Health subjects with the HLA-DQ rs9275572 GA genotype would have a 0.641 (95 % CI 0.416, 0.985; P = 0.043) times lower odds of having HCC, and those with the AA genotype would have a 0.256 (95 % CI 0.106, 0.618; P = 0.002) times lower odds of having HCC, whereas the values of the other covariates were fixed. Whereas there was no significant difference found for the HLA-DQ rs2856718 AG and GG genotype. Our study suggested that HLA-DQ loci (rs9275572) were associated with HBV-related HCC as a protective factor in Han Chinese.

Host nucleotide polymorphism in hepatitis B virus-associated hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is etiologically linked with hepatitis B virus (HBV) and is the leading cause of death amongst 80% of HBV patients. Among HBV affected patients, genetic factors are also involved in modifying the risk factors of HCC. However, the genetic factors that regulate progression to HCC still remain to be determined. In this review, we discuss several single nucleotide polymorphisms (SNPs) which were reportedly associated with increased or reduced risk of HCC occurrence in patients with chronic HBV infection such as cyclooxygenase (COX)-2 expression specifically at COX-2 -1195G/A in Chinese, Turkish and Egyptian populations, tumor necrosis factor α and the three most commonly studied SNPs: PAT-/+, Lys939Gln (A33512C, rs2228001) and Ala499Val (C21151T, rs2228000). In genome-wide association studies, strong associations have also been found at loci 1p36.22, 11q22.3, 6p21 (rs1419881, rs3997872, rs7453920 and rs7768538), 8p12 (rs2275959 and rs37821974) and 22q11.21. The genes implicated in these studies include HLA-DQB2, HLA-DQA1, TCF19, HLA-C, UBE2L3, LTL, FDX1, MICA, UBE4B and PG. The SNPs found to be associated with the above-mentioned genes still require validation in association studies in order to be considered good prognostic candidates for HCC. Screening of these polymorphisms is very beneficial in clinical experiments to stratify the higher or lower risk for HCC and may help in designing effective and efficient HCC surveillance programs for chronic HBV-infected patients if further genetic vulnerabilities are detected.

Tumor Necrosis Factor-α-308 G/A Polymorphisms and Risk of Hepatocellular Carcinoma: A Meta-Analysis

CONTEXT

Hepatocellular carcinoma (HCC) is a common disorder throughout the world that can develop due to various factors, including genetics. Tumor necrosis factor-α (TNF-α) is the most frequently studied cytokine related to the risk of developing HCC, and an association between the 308 position of the TNF-α promoter (TNF-α-308) and HCC risk has been confirmed in various reports.

EVIDENCE ACQUISITION

The PubMed, Scopus, and Google Scholar databases were searched through July 12, 2015, for studies on associations between TNF-α-308 and the risk of HCC. To determine this association, odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated.

RESULTS

A total of 23 case-control studies were investigated, involving 3,389 cases and 4,235 controls. The overall conclusion was that the A allele was more frequent in case groups compared to control groups (13.4% vs. 8.4%). Thus, the A allele was significantly associated with increased HCC risk (OR = 1.77; 95% CI = [1.26-2.50]; P value < 0.002). In addition to the allelic model, the dominant model (AA + AG vs. GG) was significantly associated with HCC risk (OR = 1.80; CI = [1.29-2.51]; P value < 0.001). In the sensitivity analysis for co-dominant (AA vs. GG) and recessive models (AA vs. AG + GG), no trustworthy associations with the risk of HCC development were observed.

CONCLUSIONS

This meta-analysis indicated that the TNF-α-308 G/A polymorphism is significantly associated with increased susceptibility to HCC. However, to confirm this finding, more studies are needed on TNF-α-308 G/A polymorphisms associated with HCC.

Association between the HLA-DQB1 polymorphisms and the susceptibility of chronic hepatitis B: A comprehensive meta-analysis

Single-nucleotide polymorphisms in the human leukocyte antigen (HLA)-DQB1 gene are associated with chronic inflammatory and immunological diseases. Host genetic factors have a key role in the development of chronic hepatitis B (CHB). The aim of the present study was to investigate the association between the HLA-DQB1 polymorphisms and the susceptibility to CHB. PubMed, Embase, CNKI and Wanfang databases were searched for the studies that reported the association of the HLA-DQB1 polymorphisms with CHB between January 1, 1966 and July 30, 2015. HLA-DQB1 polymorphism-specific odds ratio (OR) and 95% confidence intervals (95% CI) were pooled and calculated in the fixed effects model using the Mantel-Haenszel method. Q-test and I² test were performed to examine the heterogeneity. Begg's funnel test and Egger's test were conducted to assess publication bias. All the statistical tests were two-tailed. Subsequent to searching the databases and screening according to the inclusion criteria, 7 case-control studies were available in the present meta-analysis, including 815 CHB patients and 731 control subjects for the HLA-DQB1 polymorphisms. In conclusion, the statistically significant pooled OR of the HLA-DQB1 polymorphisms were obtained for the HLA-DQB1 loci (*0201, case vs.

CONTROL

I²=36.5%; P-value of heterogeneity=0.15; OR, 1.29; 95% CI, 1.02-1.64; P=0.0301; *0301, case vs.

CONTROL

I²=0%; P-value of heterogeneity=0.899; OR, 1.37; 95% CI, 1.12-1.69; P=0.002; *0502, case vs.

CONTROL

I²=24.9%; P-value of heterogeneity=0.239; OR, 1.50; 95% CI, 1.02-2.20; P=0.04), which were associated with an increased risk of CHB. Similar significant results were observed and acquired in the following HLA-DQB1 loci (*0303, case vs.

CONTROL

I²=0%; P-value of heterogeneity=0.986; OR, 0.77; 95% CI, 0.62-0.95; P=0.017; *0604, case vs.

CONTROL

I²=0%; P-value of heterogeneity=0.594; OR, 0.38; 95% CI, 0.20-0.74; P=0.003), which were associated with a decreased risk of CHB. No significant association was observed for the other HLA-DQB1 family loci. The present meta-analysis demonstrated that the HLA-DQB1 loci (*0201, *0301 and *0502) polymorphisms were significantly associated with an increased risk of CHB. However, HLA-DQB1 loci polymorphisms (*0303 and *0604) were associated with a decreased risk of CHB. These results support the hypothesis that polymorphisms of the HLA-DQB1 allele families may affect the susceptibility or resistance to CHB.

The Correlation Between Interferon Lambda 3 Gene Polymorphisms and Susceptibility to Hepatitis B Virus Infection

BACKGROUND

Cytokines are proteins that mediate innate and adaptive immunity responses. It is hypothesized that interferon lambda 3 (IFNL3) levels can influence the outcome of chronic hepatitis B virus (HBV) infection. Polymorphisms in IFN genes have been associated with response to infection.

OBJECTIVES

This study was carried-out to investigate the association of IFNL3 gene polymorphisms (rs12979860 and rs8099917) with HBV susceptibility, in chronic HBV-infected patients.

PATIENTS AND METHODS

In this case-control study, we determined IFNL3 single nucleotide polymorphisms (SNPs) (rs12979860 and rs8099917) in 221 individuals, with chronic HBV infection, and 200 healthy individuals, who were voluntary blood donors, with negative test for HBV. Alleles and genotypes analyses were performed by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods.

RESULTS

The frequencies of the rs12979860 and rs8099917 genotypes were not significantly different between the HBV-infected and the control groups (CC:CT:TT of 30.3%:48.0%:21.7% vs. 33.0%:49.0%:18.0%, P > 0.05, and GG:GT:TT of 5.8%:39.4%:54.8% vs. 5.0%:41.0%:54.0%, P > 0.05, respectively). Also, the frequencies of the alleles were not significantly different between both groups (C:T of 54.3%:45.7% vs. 57.5%:42.5%, P > 0.05, and G:T of 25.6%:74.4% vs. 25.5%:74.5%, P > 0.05, respectively) and the chronic HBV infection. There were no significant differences between patients, with at least one rs12979860C and or rs8099917T alleles compared to the healthy controls (rs12979860: CT + CC:TT, OR = 1.26, 95%CI = 0.78 - 2.04, P = 0.341 and rs8099917: GT + TT:GG, OR = 1.03, 95%CI = 0.70 - 1.51, P = 0.877, respectively).

CONCLUSIONS

Our study showed no correlation between rs12979860 and rs8099917 SNPs and chronic HBV infection. Further studies, with larger sample sizes and different ethnicities, are necessary to validate our findings.

Interaction Between Polymorphisms of IFN-γ and MICA Correlated with Hepatocellular Carcinoma

Background

We explored the relationship of interferon--γ (IFN-γ) and MHC class-I chain related gene A (MICA) genes polymorphisms with hepatocellular carcinoma (HCC) risk, and tried to determine whether the interaction existed between these two genes polymorphisms on the basis of HCC.

Material/Methods

Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to detect the genotypes of the 3 single-nucleotide polymorphisms (SNPs) and to analyze the correlation of each SNP with HCC susceptibility in 120 HCC patients and 124 healthy people. The association strength between the 3 SNPs and HCC is represented with odds ratio (OR) and 95% confidence interval (95% CI). Hardy-Weinberg equilibrium (HWE) was tested by χ² test in the control group.

Results

GG genotype of IFN-γ rs2069727 polymorphism had apparently different distributions in case and control groups (P<0.05), and might confer increased risk of HCC (OR=3.40, 95%CI=1.23–9.38). Analysis of MICA rs2596542 polymorphism also yielded the same result (OR=2.90, 95%CI=1.10–7.67), as did their risk alleles. Specifically, the interaction between rs2596542 and rs2069705 polymorphisms increased the HCC risk by 1.41 times and between rs2596542 and rs2069727 polymorphisms the increased risk of HCC by 5.56 times.

Conclusions

IFN-γ rs2069727 and MICA rs2596542 polymorphisms may be related to the incidence of HCC. Interaction exists between the polymorphisms of IFN-γ and MICA, which may increase risk of HCC.

Analysis of IL-10 and IL-6 Gene Polymorphisms and Their Serum Levels in Patients with Brucellosis: A Case Control Study

BACKGROUND

It seems that polymorphism in the regulatory areas of cytokine genes affects the cytokine production capacity and may play a role in the development of infectious diseases. Interleukin-10 (IL-10) and Interleukin-6 (IL-6), which are cytokines of Th2, cause the macrophage become inactive and patient conditions get worse.

METHODS

In this case-control study, 60 patients with brucellosis and 60 healthy participants were recruited. IL-10 genotyping at positions -1082 (G/A), -819 (C/T), and -592 (C/A) and IL-6 genotyping at position -174 (G/C) were analyzed by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) methods. The levels of IL-10 and IL-6 were determined by a sandwich enzyme-linked immunosorbent assay in sera of study population.

RESULTS

The AA and CC genotypes of the IL-10 gene at positions -1082 G/A and -819 C/T were significantly more frequent in patients in comparison to controls, respectively. The AG genotype of the IL-10 gene at positions -1082 G/A was significantly more frequent in control groups than the patients. Serum levels of IL-10 and IL-6 were significantly more frequent in the patients than in the control groups.

CONCLUSIONS

Our study showed that the AA and CC genotypes at positions -1082 and -819 are very important, respectively. These results suggest that IL-10 (-1082 G/A) GG genotype may be considered as a risk factor for brucellosis, while the AG genotype might be a protective factor against the disease.

Tumor necrosis factor (TNF)-α -308G/A (rs1800629) polymorphism distribution in North India and its association with pemphigus: Case-control study and meta-analysis

Pemphigus is an autoimmune blistering disorder of skin and/or mucosal surfaces characterized by intraepithelial lesions and immunoglobulin-G autoantibodies against desmogleins (proteins critical in cell-to-cell adhesion). Genetic, immunological, hormonal, and environmental factors are known to contribute to its etiology. Tumor necrosis factor-alpha (TNF-α) which plays a key role in pathogenesis of many infectious and inflammatory diseases has been found in high levels in lesional skin and sera of pemphigus patients. However, studies on association of single nucleotide polymorphism (SNP) in promoter region of TNF-α at position -308 affecting G to A transition with pemphigus has been scarce. This study was conducted to evaluate the TNF-α -308G/A SNP distribution in North Indian cohort, and to define the association between the TNF-α -308G/A SNP distribution and pemphigus, globally, by means of meta-analysis. TNF-α -308G/A SNP in pemphigus patients was investigated by cytokine genotyping using genomic DNA by PCR with sequence-specific primers. Meta-analysis of the data, including four previously published studies from other populations, was performed to generate a meaningful relationship. The results of our case-control study indicate non-significant differences between patients and controls in TNF-α -308G/A SNP. The meta-analysis also revealed that TNF-α -308G/A SNP is not associated with pemphigus risk in population at large; however, it may be contributing towards autoimmune phenomenon in pemphigus by being a part of its multi-factorial etiology. This study provides evidence that the TNF-α -308G/A polymorphism is not associated with overall pemphigus susceptibility. Nevertheless, further studies on specific ethnicity and pemphigus variants are necessary to validate the findings.

Interferon-γ and Tumor Necrosis Factor-α Produced by T Cells Reduce the HBV Persistence Form, cccDNA, Without Cytolysis

BACKGROUND & AIMS

Viral clearance involves immune cell cytolysis of infected cells. However, studies of hepatitis B virus (HBV) infection in chimpanzees have indicated that cytokines released by T cells also can promote viral clearance via noncytolytic processes. We investigated the noncytolytic mechanisms by which T cells eliminate HBV from infected hepatocytes.

METHODS

We performed a cytokine enzyme-linked immunosorbent assay of serum samples from patients with acute and chronic hepatitis B. Liver biopsy specimens were analyzed by in situ hybridization. HepG2-H1.3 cells, HBV-infected HepaRG cells, and primary human hepatocytes were incubated with interferon-γ (IFNγ) or tumor necrosis factor-α (TNF-α), or co-cultured with T cells. We measured markers of HBV replication, including the covalently closed circular DNA (cccDNA).

RESULTS

Levels of IFNγ and TNF-α were increased in serum samples from patients with acute vs chronic hepatitis B and controls. In human hepatocytes with stably replicating HBV, as well as in HBV-infected primary human hepatocytes or HepaRG cells, IFNγ and TNF-α each induced deamination of cccDNA and interfered with its stability; their effects were additive. HBV-specific T cells, through secretion of IFNγ and TNF-α, inhibited HBV replication and reduced cccDNA in infected cells without the direct contact required for cytolysis. Blocking IFNγ and TNF-α after T-cell stimulation prevented the loss of cccDNA. Deprivation of cccDNA required activation of nuclear APOBEC3 deaminases by the cytokines. In liver biopsy specimens from patients with acute hepatitis B, but not chronic hepatitis B or controls, hepatocytes expressed APOBEC3A and APOBEC3B.

CONCLUSIONS

IFNγ and TNF-α, produced by T cells, reduce levels of HBV cccDNA in hepatocytes by inducing deamination and subsequent cccDNA decay.

The association of TNF-308 (G/A) gene polymorphisms and hepatocellular carcinoma risk: a meta-analysis

Objective

Many studies have examined the association between the TNF-308 G/A polymorphism gene polymorphisms and hepatocellular carcinoma risk in various populations, but their results have been inconsistent. To assess this relationship more precisely, a meta-analysis was performed.

Methods

The PubMed and CNKI (China National Knowledge Infrastructure) database was searched for case-control studies. Odds ratios (OR) with 95% CIs were used to determine the strength of association between the TNF-308 G/A polymorphisms and HCC risk. The pooled ORs for the risk associated with the TNF-308 G/A genotype, the A carriers (A/G + A/A) vs. the wild-type homozygotes (G/G), A/A vs. G/G were calculated, respectively. Subgroup analyses were done by ethnicity and smoking status. Heterogeneity assumptions were assessed by chi-square-based Q-test.

Results

Ultimately, 21 studies, comprising 2,923 hepatocellular carcinoma cases and 4,323 controls were included. Overall, the A carriers (G/A + A/A) vs. the wild-type homozygotes (G/G), the pooled OR was 1.05 (95% CI, 0.93-1.19; P=0.000 for heterogeneity), for A/A vs. G/G the pooled OR was 1.07 (95% CI, 0.95-1.21; P=0.007 for heterogeneity). In the stratified analysis by ethnicity, the significantly risks were found among non-Asians. However, for Asians, significantly risks were not found.

Conclusions

The TNF-308 G/A polymorphisms are not associated with hepatocellular carcinoma risk among Asians, but for non-Asians.

Quantitative assessment of common genetic variations in HLA-DP with hepatitis B virus infection, clearance and hepatocellular carcinoma development

Hepatitis B virus (HBV) infection is the predominant risk factor for chronic hepatitis B (CHB), liver cirrhosis (LC) and hepatocellular carcinoma (HCC). Recently, genome-wide association studies have identified human leukocyte antigen (HLA)-DP polymorphisms (rs3077 and rs9277535) as a new chronic HBV infection susceptibility locus. Since then, the relationship between HLA-DP polymorphisms and various outcomes of HBV infection has been reported. However, the results have been inconclusive. To derive a more precise estimation of the relationship between HLA-DP polymorphisms and various outcomes of HBV infection, a meta-analysis of 62,050 subjects from 29 case-control studies was performed. We found that rs3077 and rs9277535 in HLA-DP significantly decreased HBV infection risks and increased HBV clearance possibility in a dose-dependent manner. In the subgroup analysis by ethnicity, study design and sample size, significant associations were found for these polymorphisms in almost all comparisons. Meanwhile, haplotype analyses of the two polymorphisms revealed a significant association between the combination of these alleles and HBV infection outcomes. However, no significant results were observed in HCC development. Our results further confirm that genetic variants in the HLA-DP locus are strongly associated with reduced HBV infection and increased the likelihood of spontaneous viral clearance.

IL6 gene allele-specific C/EBPα-binding activity affects the development of HBV infection through modulation of Th17/Treg balance

Interleukin-6 (IL-6) has an important role in the pathogenesis of chronic viral hepatitis and related liver diseases. Although host genetics associated with the response to anti-viral treatment have been reported, little is known about the relationship between IL6 genetic polymorphisms and the outcome of hepatitis B virus (HBV) infection. In this study, we determined the genotype distribution of rs1800796 polymorphism in healthy controls and cases including chronic HBV (CHB), hepatitis C virus and HIV infection. The rs1800796 was found to be associated with clinical outcome of CHB in experimental and validation cohort. The rs1800796C allele has twofold higher promoter activity than G allele. Consistently, CD14(+) monocytes from subjects carrying the rs1800796C allele produced more IL-6 in response to in vitro HBV core antigen stimulation than those carrying G allele. Moreover, CHB patients carrying rs1800796C allele have significantly higher T-helper 17 (Th17) and regulatory T cell (Treg) ratio. Finally, a transcription factor C/EBPα binds in higher affinity to rs1800796C allele than to G allele. These results suggest that genetic predisposition to higher IL-6 production is associated with increased risk to HBV infection and hepatic inflammation, which might be due to C/EBPα-mediated regulatory effect on Th17 and Treg responses. Appropriate manipulation of IL-6 expression might be used to prevent and treat HBV infection.