Association of the HLA-DRB1*01 allele with spontaneous viral clearance in an Irish cohort infected with hepatitis C virus via contaminated anti-D immunoglobulin

Background/Aims: The host's immune response may influence the course of hep atitis C virus (HCV) infection. The aim of this study was to examine the di stribution of HLA Class II DRB1* alleles in a homogeneous cohort of individ uals who were infected with HCV-contaminated anti-D immunoglobulin, and to compare frequencies of alleles in individuals with spontaneous viral cleara nce to those with chronic HCV infection. Methods: HLA DRB1 typing was performed on whole blood or serum from 157 fem ales. Of these, 73 had spontaneously recovered from infection (persistently HCV RNA negative), while 84 had chronic HCV infection (persistently HCV RN A positive), A group of 5000 healthy bone marrow donors served as a control population. Results: No significant differences were observed between individuals with spontaneous viral clearance or chronic HCV infection for age, sex, alcohol consumption, source or duration of infection. The DRB1*01 allele was found significantly more frequently in individuals with viral clearance compared to those with chronic infection (27.4% vs. 7.1% p=0.001, odds ratio OR=4.9, pc=0.01), No significant association was shown between severity of liver d isease and DRB1* alleles, Conclusions: DRB1*01 is associated with spontaneous viral clearance in an I rish cohort infected with HCV via contaminated anti-D immunoglobulin, HLA-D RB1* genes do not appear to influence severity of liver disease. These resu lts suggest that host HLA-DRB1* alleles are important contributors to disea se outcome.