DETECTION OF A 5'-UTR VARIATION IN THE HCV GENOME AFTER LONG-TERM IN-VITRO INFECTION

The TOFE lymphoid cell line from normal human bone marrow is susceptib le to infection by a hepatitis C virus (HCV) serum strain. A sequence analysis of the 5' untranslated region (UTR) of HCV before and after l ong-term in vitro infection revealed one base substitution at position -158 (C > T) of the 5' UTR. We performed the direct sequencing of 5' UTR polymerase chain reaction-amplified sequences of the HCV genome: a ) from the original serum-derived strain; b) from TOFE cell extracts 6 months post infection. This base substitution in the regulatory eleme nts of the 5' UTR might be related to the ability of the virus to grow in cell culture.