BINDING OF HEPATITIS-C VIRUS TO CD81

Chronic hepatitis C virus (HCV) infection occurs in about 3 percent of the world's population and is a major cause of liver disease. HCV inf ection is also associated with cryoglobulinemia, a B Lymphocyte prolif erative disorder. Virus tropism is controversial, and the mechanisms o f cell entry remain unknown. The HCV envelope protein E2 binds human C D81,a tetraspanin expressed on various cell types including hepatocyte s and B Lymphocytes. Binding of E2 was mapped to the major extracellul ar Loop of CD81. Recombinant molecules containing this loop bound HCV and antibodies that neutralize HCV infection in vivo inhibited virus b inding to CD81 in vitro.