Polymorphisms of interleukin-1R receptor antagonist genes in patients with chronic hepatitis B in Iran

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 Interleukin-1β and Gene Polymorphisms with Liver Pathogenesis in Hepatitis B Virus Infection among Eastern Indian Population

BACKGROUND

Interleukin-1β (IL-1β) is an important member of the family of the proinflammatory cytokines that modulate outcome of hepatitis B virus (HBV) infection.

OBJECTIVES

This study was designed to investigate the relationship between the polymorphic genotypes of the interleukin-1β (IL-1β) promoter region and the interleukin-1 receptor antagonist gene (IL-1RN) and disease outcome in HBV-infected individuals.

METHODS

DNA was extracted from 395 study subjects including HBV carriers with varying clinical presentations, as well as healthy controls and spontaneously recovered cases (SRC). Polymorphisms in IL-1β (at position -511) and IL-1RN (variable nucleotide tandem repeats, VNTR) were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and PCR based assay respectively.

RESULTS

Among the study subjects, different IL-1β (at position -511) (CC, CT and TT) and IL-1RN (1/1, 1/2, 2/2 and 1/3) polymorphic genotypes were found at variable proportions. Logistic regression analysis revealed, no notable difference at the level of IL-1β promoter (P = 0.244; OR = 0.78; 95% CI = 0.52-1.18) or IL-1RN genotype polymorphism (P = 0.840; OR = 1.03; 95% CI = 0.78-1.36) among the HBV carriers and controls or SRC cases. Pairwise proportion testing showed, IL-1β -511 genotype CC was significantly higher among asymptomatic carriers (ASC) in comparison with liver cirrhosis (LC) patients (P value = 0.028) and healthy control group (P-value = 0.036). IL-1RN genotype 2/2 was considerably higher in LC group than SRC as well as control group. Combinations of IL-1β (-511) and IL-1RN polymorphisms were associated with disease progression, such as CC-1/2 with ASC and TT-2/2 with LC.

CONCLUSION

IL-1β polymorphisms are found to be associated with disease severity. Different polymorphic combinations are associated with degree of disease severity. Overall this is the first report from Eastern India, which shows association of IL-1β polymorphisms with HBV-related hepatic complications.

The impact of biologic response modifiers on hepatitis B virus infection

INTRODUCTION

The biologic response modifiers are a diverse group of medications that have emerged over the last decade. They target pro-inflammatory cytokines or cell surface molecules that drive illnesses such as rheumatoid arthritis. Despite the greater control afforded they have also ushered in a new spectrum of side effects. As the same immunologic machinery that helps control infections such as HBV contributes to the pathogenesis of rheumatologic diseases, persistence or reactivation of the virus remains an evolving concern.

AREAS COVERED

A systemic literature review was performed using the PubMed and Medline databases (1996 to January 2010) searching for the index term 'Hepatitis B' combined with the terms 'tumor necrosis factor', 'B cell', 'rituximab', 'IL-1', 'anakinra', 'IL-6', 'tocilizumab', 'CTLA-4', and 'abatacept'. All relevant articles in English were reviewed and secondary references of interest were also retrieved. This paper addresses the role of the various cytokines and cluster of differentiation molecules in controlling HBVinfection and the currently known effect that the biologic response modifiers have on viral control by the host immune response.

EXPERT OPINION

The risk of HBV reactivation is greatest in HBsAg positive patients. These patients should start antiviral therapy one week before receiving a biologic response modifier. The risk of HBV reactivation in HBsAg negative patients appears very low but when HBsAb titers are low use of rituximab or TNF-α antagonists may increase the risk of reactivation.

Gender-related distribution of the interleukin-1 beta and interleukin-1 receptor antagonist gene polymorphisms in patients with end-stage liver disease

Interleukin-1 beta (IL-1 beta) genetic polymorphisms and IL-1 receptor antagonist (IL1RN) variable number tandem repeat (VNTR) seem to be related with the occurrence of chronic diseases. This study aimed to verify whether IL-1 beta -511>C/T, -31>T/C, +3953>C/T and IL1RN VNTR were associated to the development of liver cirrhosis. Two hundred forty cirrhotic patients were involved in the study. A significant trend was detected, for increasing cirrhosis frequencies, grouping the patients as follows: females and males carrying neither the IL-1 beta (-511 -31) T-C/T-C or T-C/(T-T or C-C) diplotypes nor any IL1RN A2 allele (138/292), males carrying either the IL-1 beta T-C/T-C or T-C/(T-T or C-C) diplotypes or at least one IL1RN A2 allele (74/147) and males carrying either the IL-1 beta T-C/T-C or T-C/(T-T or C-C) diplotypes and at least one IL1RN A2 allele (28/37) (p < 0.01). IL-1 beta polymorphisms are associated with the occurrence of end stage liver disease. IL-1 beta inflammatory activity appears more pronounced in males.