Objective: To get more new information about the antigen epitopes of the hypervariable region 1 (HVR1) within the putative envelope glycoprotein of hepatitis C virus (HCV).
Methods: We designed and synthesized linear epitope peptides (LP) and multiple antigen peptide (MAP, symmetric 8 branches) derived from 22 amino acids (position 390-411aa) of HCV-BJ (HCV 1b genotype) HVR1. We compared the binding-reactivity of LP with MAP to native anti-HVR1 antibody in HCV-infected patients sera. In addition, the HCV genotype was tested to assess the prevalence of anti-HVR1 by cleaving PCR products with restriction enzyme.
Results: (1)There was a significant difference (P< 0.0001) of mean A450 between anti-MAP (mean +/- s =0.461 +/- 0.590) and anti-LP (mean +/- s =0.145 +/- 0.166), and the immunoreactivity of MAP and LP to the native antibody had a significant association (P < 0.001). (2)The rate of anti-LP and anti-MAP detection in 59 anti-HCV2.0 positive sera was 29% and 58% respectively. (3)The binding of MAP to antibody protein in sera from patients infected with other genotypes besides HCV 1b genotype was observed.
Conclusion: The binding-reactivity of MAP to native antibody was obviously higher than that of LP, and there is a cross-reaction between them. It was possible to analyse conformational antigen epitopes in the region and develop HCV molecular vaccine by synthesizing MAP corresponding to HCV HVR1 sequences.