Characterization of monoclonal antibodies to hepatitis E virus (HEV) capsid protein and identification of binding activity.

Twenty-seven monoclonal antibodies (Mabs) recognizing the open reading frame 2 structural protein of the Pakistan strain of hepatitis E virus (HEV) were generated by conventional hybridoma technique. These Mabs were characterized by ELISA, affinity-capture reverse transcriptase-polymerase chain reaction (AC/RT-PCR), immune electron microscopy (IEM), and a RT-PCR based seroneutralization assay. Twenty-seven Mabs were positive by ELISA. By AC/RT-PCR, 24 Mabs bound to Pakistan and Namibia HEV strains. Thirteen Mabs were examined by IEM. Nine Mabs, positive by ELISA and AC/RT-PCR, bound and aggregated to Mexican HEV strain. We tested five Mabs that were positive by ELISA, AC/RT/PCR, and IEM by a RT-PCR based seroneutralization assay. Only one Mab (Mab 7) showed activity that inhibited the ability of HEV to attach to Alexander hepatoma cells (PLC-PRF-5). When Mab 7 was diluted to 1: 160, its inhibition activity persisted suggesting that Mab 7 might be a potential candidate for further evaluation in primates (passive protection experiments).