HCV replication in mononuclear cells stimulates anti-HCV-secreting B cells and reflects nonresponsiveness to interferon-alpha.

Recently, it was demonstrated in chronic hepatitis C that the release of IgG and IgM anti-HCV antibodies by mononuclear cells (PBMCs) correlated with inflammatory activity, HCV persistence in serum, and negative outcome from antiviral therapy. Thus, persistent antigenic stimulation of the antibody-secreting B cells has been suggested. In this study, PBMCs were derived from 13 patients with chronic hepatitis C. Nucleic acids were extracted by the guanidine-thiocyanate-method, and plus- and minus-stranded HCV-RNAs were determined using primers from the 5'-untranslated region of HCV. Simultaneously, unstimulated PBMCs were cultured for 8 days and anti-HCV antibodies were detected in the supernatants by EIA and RIBA. Seven patients (53.8%) had both plus- and minus-stranded HCV-RNA in PBMCs, while anti-HCV antibodies were secreted in vitro. One of 2 patients with plus- but not minus-stranded HCV-RNA in PBMCs was anti-HCV positive in vitro, whereas 4 patients without HCV-infected PBMCs were anti-HCV negative in vitro. Eight patients received antiviral therapy with interferon-alpha 2b. Four nonresponders and 1 partial responder had plus- and minus-stranded HCV-RNA in PBMCs and anti-HCV secretion in vitro. On the other hand, 2 complete responders and another partial responder showed neither HCV infection of PBMCs nor anti-HCV secretion in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)