Genetic diversity of hepatitis C virus predicts recurrent disease after liver transplantation.

Approximately 20% of patients receiving liver transplants for end-stage hepatitis C rapidly develop severe allograph fibrosis within the first 24 months after transplant. Hepatitis C virus (HCV) variants were studied in 56 genotype-1-infected subjects with end-stage hepatitis C disease at the time before and 12 months after liver transplant, and post-transplant outcome was followed with serial liver biopsies. In 15 cases, pre-transplant HCV genetic diversity was studied in detail in liver (n=15), serum (n=15), peripheral blood mononuclear cells (n=13), and perihepatic lymph nodes (n=10). Our results revealed that pre-transplant HCV genetic diversity predicted the histological outcome of recurrent hepatitis C disease after transplant. Mild disease recurrence after transplant was significantly associated with higher genetic diversity and greater diversity changes between the pre- and post-transplant time points (p=0.004). Meanwhile, pre-transplant genetic differences between serum and liver were related to a higher likelihood of development of mild recurrent disease after transplant (p=0.039).

HIV infection and antiretroviral therapy: effect on hepatitis C virus quasispecies variability.

BACKGROUND: Hepatitis C virus (HCV) quasispecies variability has been associated with liver disease progression. The effects of human immunodeficiency virus (HIV) coinfection and highly active antiretroviral therapy (HAART) on HCV quasispecies variability have not been firmly established. METHODS: We determined HCV quasispecies complexity and diversity in 69 subjects, 28 of whom were HIV infected, using clonal frequency analysis via heteroduplex mobility analysis of the second envelope gene hypervariable region. Nucleotide sequencing was performed for a small subset of subjects. RESULTS: HIV-positive, HAART-naive subjects had significantly lower HCV quasispecies complexity and diversity than did both HIV-negative and HIV-positive HAART-treated subjects. In multivariate analysis, HIV infection predicted decreased complexity (P < .0001) and diversity (P = .001) of HCV quasispecies, whereas HAART predicted increased complexity (P = .013) and diversity (P = .026). For 4 of 6 patients, sequence analysis yielded data supporting the model that positive host pressure drives HCV quasispecies heterogeneity, although data favoring the hypothesis of selective outgrowth of the most fit variants were also observed. CONCLUSION: HIV coinfection is associated with decreased HCV quasispecies variability, which appears to be reversed by effective HAART. Although HIV- and HAART-related effects on host immune pressure are likely to play a role in the observed differences in HCV genetic heterogeneity, other mechanisms may be operative.