Association of human leukocyte antigen DQB1 and DRB1 alleles with chronic hepatitis B

AIM

To investigate the effect of human leukocyte antigen (HLA) DRB1 and DQB1 alleles on the inactive and advanced stages of chronic hepatitis B.

METHODS

Patient records at a single institution's hepatology clinic were reviewed. Demographic data, laboratory results, endoscopy results, virological parameters, biopsy scores and treatment statuses were recorded. In total, 355 patients were eligible for the study, of whom 226 (63.7%) were male. Overall, 82 (23.1%) were hepatitis B early antigen (HBeAg) positive, 87 (24.5%) had cirrhosis, and 66 (18.6%) had inactive disease. The presence of DQB1 and DRB1 alleles was determined by polymerase chain reaction with sequence-specific primers. The distribution of the genotyped alleles among patients with cirrhosis and patients with chronic active hepatitis was analyzed.

RESULTS

The most frequent HLA DQB1 allele was DQB1*03:01 (48.2%), and the most frequent HLA DRB1 allele was DRB1*13/14 (51.8%). DQB1*05:01 was more frequent in patients with active disease than in inactive patients (27% vs 9.1%; P = 0.002, Pc = 0.026). DRB1*07 was rare in patients with cirrhosis compared with non-cirrhotics (3.4% vs 16%; P = 0.002, Pc = 0.022). Older age (P < 0.001) and male gender (P = 0.008) were the other factors that affected the presence of cirrhosis. In a multivariate logistic regression analysis, DRB1*07 remained a significant negative predictor of cirrhosis (P = 0.015). A bioinformatics analysis revealed that a polymorphic amino acid sequence in DRB1*07 may alter interaction with the T-cell recognition site.

CONCLUSION

This study demonstrates that HLA alleles may influence cirrhosis development and disease activity in Turkish chronic hepatitis B patients.

HLA DQB1 alleles are related with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease. NAFLD is a complex disease and inflammation is a crucial component in the disease pathogenesis. Recent genome wide association studies in hepatology area highlighted significant relations with human leukocyte antigen (HLA) DQ region and certain liver diseases. The previous animal models also emphasized the involvement of adaptive immune system in the liver damage pathways. To investigate possible polymorphisms in the HLA region that can contribute to the immune response affecting the NAFLD, we enrolled 93 consecutive biopsy proven NAFLD patients and a control group consisted of 101 healthy people and genotyped HLA DQB1 alleles at high resolution by sequence specific primers-polymerase chain reaction. The mean NAFLD activity score (NAS) was 5.2 ± 1.2, fibrosis score was 0.9 ± 0.9, ALT was 77 ± 47.4 U/L, AST was 49.4 ± 26.3 U/L. Among 13 HLA DQB1 alleles analyzed in this study, DQB1*06:04 was observed significantly at a more frequent rate among the NAFLD patients compared to that of healthy controls (12.9 vs. 2 % χ(2) = 8.6, P = 0.003, P c = 0.039, OR: 7.3 95 % CI 1.6-33.7). In addition, the frequency of DQB1*03:02 was significantly higher in the healthy control group than the NAFLD patients (24.8 vs. 7.5 %, χ(2) = 10.4, P = 0.001, P c = 0.013, OR: 0.2, 95 % CI 0.1-0.6). NAFLD patients were grouped according to their fibrosis score and NAS. The distribution of DQB1 alleles over stratified NAFLD patients did not reveal any statistically significant relation. Taken together, immune repertoire of individuals may have an effect on NAFLD pathogenesis and therefore, in NAFLD, adaptive immunity pathways should be investigated.

Anthrax: a disease in waiting?

Anthrax was a relatively unknown disease in the Western world until 2001, when spores were maliciously mailed in the US, causing five deaths. The mortality of the disease, the stability of its spores and the subsequent lack of person-to-person spread make anthrax an attractive biological weapon for terrorists with a desire for targeted mass destruction.

The effect of HLA-DQB1 alleles on virologic breakthroughs during chronic hepatitis B treatment with genetically low barrier drugs

BACKGROUND

Chronic hepatitis B treatment with oral antiviral drugs is a long course. During this course, antiviral resistance is a serious issue, particularly, if genetically low barrier drugs are in use. Host immunity is accepted to have an effect on antiviral resistance development. The earliest clinical sign of drug resistance is virologic breakthrough. In this study, we aimed to investigate the relation between HLA-DQB1 alleles and virologic breakthrough events.

SUBJECTS AND METHODS

The patient records at single institution hepatology clinic were reviewed. Local institution ethics committee approval was taken. The patients' demographic data, virologic parameters, treatment statues were noted. Patients who had received lamivudine or adefovir were recruited and grouped into two according to virologic breakthrough occurrence. Patients who were not compliant to the given treatment were excluded. Blood samples were taken for DNA extraction. HLA-DQB1 alleles were determined at high level by sequence-specific primers-polymerase chain reaction. The distribution of DQB1 alleles among groups was analyzed.

RESULTS

One hundred ninety-eight patients were eligible for the study. Ninety-six of them had virologic breakthrough where 102 did not have. DQB1 0503 allele was more frequent in patients without breakthrough (28.4% vs. 12.4%, P=0.006). In univariate analysis, HBeAg seropositivity (P<0.001), absence of cirrhosis (P=0.007), younger age (P=0.002) and higher pretreatment logDNA (P<0.001) were related to breakthrough events. However, in multivariate analysis only logDNA (P<0.001) and DQB1*0503 (P=0.02) allele revealed statistically significant relation with breakthrough events.

CONCLUSION

Host immunity may have an effect on outcome during treatment with oral antiviral drugs. A patient with better immunologic profile may suppress the viral replication better and this may cause less resistance occurrence during treatment with genetically low barrier drugs.