HLA EXPRESSION IN TYPE-A MIXED CRYOGLOBULINEMIA AND CHRONIC HEPATITIS-C VIRUS

Objective. Hepatitis C virus infection is closely associated not only with hepatic damage, but also with mixed cryoglobulinemia (MC) and oth er autoimmune and lymphoproliferative disorders. Because HCV is both h epatotropic and lymphotropic, the aim of this study was to investigate whether the genetic background may influence the clinical pattern see n in different patients. Method, Two groups of patients with HCV infec tion were studied: Id with type II MC and 18 with chronic active hepat itis (CAH). 120 bone marrow donors were considered as the control grou p. In all patients HLA-A-B-C antigens were evaluated using the microly mphotoxicity technique, and HLA-DR by the PCR-SSP method Results, The frequency of the HLA antigens expressed was not precisely defined in t he two groups. However, the HLA-B51 and B35 antigens, which are often correlated with autoimmune disorders, were highly expressed in the MC patients (31.2%) compared to the controls (6.9%) and to the CAH group (11%). Moreover HLA-A9 with its split A24 were present in 50% of the M C patients. More interesting was the expression of the HLA-DR7 antigen , which was found only in the CAH group, suggesting that it may influe nce the specific liver involvement in HCV infections. Conclusion, Thes e findings indicate that the HLA system may play an important role in the clinical manifestations of HCV infection.