Impact of human leukocyte antigen-B specific Bw4 epitope on hepatitis C virus infection / 中华传染病杂志

ABSTRACT

Objective To study the impact of human leukocyte antigen (HLA)-B specific Bw4 epitope on disease progression of hepatitis C virus (HCV) infection.Methods Eighty-six cases of HCV infection through paid blood donation were enrolled in the study.Enzyme-linked immunosorbent assay (ELISA) to detect HCV IgG and IgM,real-time reverse transcriptation polymerase chain reaction (RT-PCR) to detect HCV RNA,and sequence specific primer-polymerase chain reaction (SSP-PCR) to analyze HLA type was performed.Categorical data were analyzed by chi-square test,and measurement data were compared by independent sample t test.Results Among the 86 HCVinfected individuals,there were 29 (33.7 ％) cases of Bw4/4 homozygote,38 cases (44.2 ％) of Bw4/6 heterozygote and 19 (22.1％) cases of Bw6/6 homozygote.The HCV RNA levels in Bw4/4 group,Bw4/6 group and Bw6/6 group were (3.98±0.32),(5.22±0.29),(5.04±0.38) lg IU/mL,respectively.The HCV RNA level in Bw4/4 group was significantly lower than those in the other two groups (t=2.821,P=0.0063 ; t =2.106,P =0.0407,respectively).The spontaneous clearance rates of Bw4/4 group,Bw4/6 group and BW6/6 group were 58.6％,26.3％ and 21.0％,respectively.The spontaneous clearance rate of Bw4/4 group was significantly higher than those of Bw4/6 group and Bw6/6 group (x2 =7.135,P =0.008; x2 =6.583,P =0.010,respectively).HCV infected individuals with homozygous epitopes of Bw4/4 had 4.351 times higher probability of spontaneous viral clearance than that of Bw4/6 heterozygote or Bw6/6 homozygote (OR=4.351,95％CI1.676-11.294).Conclusions Homozygosity for HLA-Bw4-bearing B alleles is associated with significant lower HCV viral load and higher spontaneous clearance rate.The HLA-Bw4 epitopes have a protective effect against HCV infection.