NEW HEV ANTIGENIC PEPTIDE AND METHODS

摘要

A highly immunoreactive viral peptide, E2, of the hepatitis E virus (HEV) genome, derived from the carboxyl terminal end region of ORF2, is disclosed. The ORF2 peptid e, expressed either as a glutathione S-transferase (GST) fusion peptide (GE2) o r as the viral peptide (E2) cleaved from sepharose-bound GE2, proved to be highly reactive with sera from patients having current or past infection with HEV. A special feature o f E2 is that it is a conformational antigenic determinant generated by intramolecular interactions between monomers of the peptide to form homodimers. The immunoreactivity is strictly conformational in nature and is only functional when the E2 peptide is in a dimeric form such that immunoreactivity is lost upon dissociation of the dimer. Moreover, diagnostic methods useful in detecting HEV infection and an antigen vaccine composition effective in preventing hepatitis E virus infection in which E2 is utilized are also disclosed.