LYMPHOTROPISM OF HEPATITIS-B AND HEPATITIS-C VIRUSES - AN UPDATE AND A NEWCOMER

The mechanisms of viral persistence are complex and include infection of the lymphoid cells. In the case of hepatitis B virus, early observa tions have suggested that HBV may infect peripheral blood mononuclear cells (PBMC). In animal models studies in chronic hepatitis B patients have further confirmed that viral DNA replicative intermediates, as w ell as viral transcripts and proteins, can be detected in PBMC under c ertain conditions. The consequences of this lymphotropism are not full y understood, but it seems likely that PBMC represent an extrahepatic reservoir of virus. The ability of hepatitis C virus to infect PBMC ha s been demonstrated in vivo and in vitro. The link between HCV lymphot ropism and both the natural history of the viral infection and the imm unological disorders frequently observed in HCV infections still needs to be established. In both cases, the infection of PBMC by HBV or HCV may represent the source of infection of the liver graft in patients transplanted for end-stage liver disease associated with HBV or HCV.