Abstract
E2/NS1 region, putative surface antigen of hepatitis C virus (HCV), contains two hypervariable regions (HVRs). To get insight of the clinical significance of HVRs, detecting system for E2/NS1 protein was established using 5 kinds of polyclonal antibodies against recombinant proteins of the regions expressed in E. coli.
As low as 10 ng of the recombinant proteins were specifically detected in this system. Crossreaction studies of the 5 antibodies against the proteins suggested that heterogeneity of amino acid sequences in HVRs is closely correlative with affinity of the antibodies. A protein corresponding to size of 44 kDa was specifically observed in a liver sample from a patient with chronic active hepatitis C using this system. Also, reactivity of the 44 kDa protein against the antibodies was different among these 5 antibodies.
Thus, these results indicate that HVRs may have an important role on immune system against HCV.
