Viral specificity of hepatitis E virus antigens identified by fluorescent antibody assay using recombinant HEV proteins.

A fluorescent antibody (FA) assay for hepatitis E virus antigen (HEVAg) in infected liver tissue was used to confirm the presence of virus-specific antigens in hepatocytes during the course of infection. With the cloning of the HEV genome it is now possible to determine which viral antigens are recognized by this FA assay. Recombinant HEV proteins covering the carboxyl half of HEV open reading frame 2 (ORF2) were used in this study to demonstrate that some of the most immunoreactive virus-specific antigens detected by FA are contained within this region of ORF2 (nucleotides 6169-7126).