HCV genotypes in bone marrow and peripheral blood mononuclear cells of patients with mixed cryoglobulinemia.

OBJECTIVE

The association of the hepatitis C virus (HCV) with the cryoglobulinemic syndrome is well known, but its pathogenetic mechanism still remains to be clarified. HCV-RNA has been found in the peripheral blood mononuclear cells (PBMC) of infected subjects. We investigated the presence of the HCV genome in bone marrow cells (BMC), and the distribution of different HCV genotypes in individuals with mixed cryoglobulinemia (MC) and in noncryoglobulinemic controls.

METHODS

15 anti-HCV positive subjects with MC, 7 non-cryoglobulinemic patients with type C chronic active hepatitis (CAH) and 2 anti-HCV negative controls were studied. HCV-RNA was detected by nested PCR of the highly conserved 5'-NCR sequence. HCV typing was carried out by means of the hybridization of the same amplified region with specific probes.

RESULTS

HCV-RNA was present in the PBMC of a large proportion of the MC patients and controls without any significant differences. On the contrary, HCV-RNA was present in the bone marrow cells of all the patients with MC and in 43% of the CAH controls. The HCV 1b and 2a genotypes seem to be the most prevalent among MC patients. Nevertheless, the patients with type II MC had a very high prevalence of the 2a genotype (77%).

CONCLUSION

The results suggest that the presence of HCV-RNA in bone marrow cells may be correlated to the pathogenetic mechanism of MC. Other studies are needed to confirm the frequent association of HCV genotype 2 with MC.