[Clinical implications of HCV quasispecies heterogeneity in patients with hepatitis C].

OBJECTIVE: To determine the heterogeneity of viral quasispecies and its clinical significance in patients with hepatitis C. METHODS: Quasispecies in the sera from 76 patients infected with hepatitis C virus were detected using single stranded conformational polymorphism (SSCP) analysis of the HCV E2 hypervariable region 1 (HVR1). RESULTS: HVR1 was amplified in 72 (94.7%) of the 76 patients. The average number of SSCP bands was 5.8, with a range from 2 to 11. The numbers of quasispecies in acute hepatitis, chronic hepatitis and liver cirrhosis and/or primary hepatocellular carcinoma were 3.1 +/- 1.2, 6.0 +/- 2.3 and 8.4 +/- 4.1, respectively. There was a statistically significant difference among them (P < 0.01). Patients with infection acquired by blood transfusion and i.v. drug use had greater number of quasispecies than those acquired by other transmission pathway (sporadic) (P < 0.05). Patients with genotype 1 a and 1 b infection had increased quasispecies compared with those infected with HCV type 2 and 3(P < 0.05). Increased quasispecies heterogeneity was significantly correlated with serum HCV RNA levels (P < 0.01). CONCLUSIONS: SSCP is a simple, rapid and reliable method for the analysis of HCV viral quasispecies heterogeneity. Quasispecies heterogeneity plays an important role in HCV persistent infection and in the progress of hepatitis C. The duration of HCV infection, HCV genotype and HCV viremia are important determinants for the evolution of HCV quasispecies heterogeneity.