Studies on Peptides. CLXVI. Solid-Phase Syntheses and Immunological Properties of Fragment Peptides Related to Human Hepatitis B Virus Surface Antigen (HBs Ag) and Its Pre-S2 Gene

Abstract

Eight fragment peptides of 25 residues each and one 26-residue fragment, covering the entire 226 amino acid sequence of human hepatitis surface antigen (HBsAg, subtype ayw), were synthesized by the solid-phase method and partially purified by gel-filtration.In addition, two fragment peptides (26-and 29-residue peptides) which cover the 55 amino acid sequence encoded in the pre-S2 gene were also synthesized and partially purified.These partially purified peptides were submitted to immunological screening.In the in vitro enzyme linked immunoassay (ELISA), a 26-residue pre-S2 gene peptide (positions 1-26) exhibited relatively high reactivity against anti-HBsAg antisera.In the in vivo assay, three fragment peptides (positions 51-75, 101-125, and pre-S2 1-26), with relatively high hydrophilicity were shown to be immunogenic in rabbit without coupling to a carrier protein.