Possible compartmentalization of hepatitis C viral replication in the genital tract of HIV-1-coinfected women

Background. We estimated the prevalence of hepatitis C virus (HCV) in cervical cytobrush samples from HCV/human immunodeficiency virus (HIV)-coinfected women and analyzed the HCV quasi species in both cytobrush and plasma samples. Possible compartmentalization of viral quasi species in the genital tract and plasma was evaluated by comparison of genetic heterogeneity and use of phylogenetic analysis. Methods. Paired plasma and cytobrush samples were obtained from 85 HCV/HIV-coinfected women. The presence of HCV in cytobrush samples was evaluated by reverse-transcription polymerase chain reaction of the 5' untranslated region. Viral quasi species were analyzed by cloning and sequencing the highly variable region-1 in 8 patients. Results. HCV was detected in 27% of cytobrush samples. The composition of viral quasi species was different in the 2 body compartments at both the nucleotide and amino acid level. In fact, the mean complexity was significantly lower in cytobrush samples, and a similar trend was observed for the other parameters of heterogeneity. Phylogenetic analysis and amino acid alignment identified several viral variants that were unique to each body compartment. Conclusions. Our data suggest that the genital and plasma quasi species represent distinct subpopulations, which possibly reflects compartmentalized viral replication. Alternatively, cell carriers harboring viral quasi species in the genital tract that are distinct from those in plasma could transfer the virus through the barrier separating the 2 body sites.