The MHC is a major determinant of viral status, but not fibrotic stage, inindividuals infected with hepatitis C

Background & Aims: In hepatitis C infection, several studies have examined the role of the major histocompatibility complex (MHC) in determining outco me, with variable results. To clarify the importance of MHC, we examined cl ass II DR and DQ antigens in a homogenous cohort of women exposed to hepati tis C genotype Ib from a single inoculum, Methods: Of 243 participants, 95 had spontaneous viral clearance and 148 are chronically infected. The frequ encies of HLA class II DR and DQ antigens were compared between the 2 group s and between liver biopsy findings of 145 chronically infected subjects, R esults: DRB1*0101 and DQB1*0501 alleles were more frequent in subjects who sustained viral clearance than in chronically infected subjects (32.3% and 36.8% vs, 8.8% and 14.2%, respectively; P = 0.002). DRB1*03011 and DQB1*020 1 occurred more frequently in chronically infected subjects than in those w ho cleared the virus (41.5% and 42.6% vs. 16.7% and 15.8%, respectively; P = 0.001), Both DRB1*03011 and DQB1*0201 were significantly less frequent in those with higher inflammatory scores on liver biopsy, Conclusions: We sho w that in a homogenous cohort of women infected with the same hepatitis C v irus, several HLA antigens are associated with either viral clearance or pe rsistence. This suggests a strong role for host immunogenetic factors in de termining outcome in hepatitis C infection.