title: Human T-helper cell responses to a synthetic peptide derived from the hepatitis B surface antigen.
abstract: Hepatitis B virus surface antigen peptide OS (aa124-147) self oligomerizes to form conformational B-cell immunogen with several properties of a candidate peptide vaccine. It gives a T-cell blastogenic response in vaccinated as well as naturally infected individuals. To study the nature and localization of the T-helper cell epitopes, the T-lymphocyte proliferative responses in humans exposed to hepatitis B surface antigen (HBsAg) were examined with a synthetic peptide representing residues 124-147 of this antigen [peptide OS (aa24-147)]. Positive responses were obtained in most cases regardless of whether HBsAg exposure was due to vaccination or a hepatitis B viral infection. Epitope localization studies with truncated peptides indicated the presence of more than two HBsAg-relevant T-helper cell epitopes. This was also corroborated by our fine mapping studies which revealed that the amino acid residues crucial for eventual T-helper cell activation were diverse amongst the various individuals. Together these studies suggest that immunization with peptide OS (aa124-147) may result in an HBsAg cross-reactive T-helper cell response in a broad spectrum of the human population.
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, New Delhi.
authors.forename: A
authors.initials: A
authors.lastname: Mishra
authors.forename: K V
authors.initials: KV
authors.lastname: Rao
authors.forename: H
authors.initials: H
authors.lastname: Durgapal
authors.forename: V
authors.initials: V
authors.lastname: Manivel
authors.forename: S K
authors.initials: SK
authors.lastname: Panda
mesh_terms: D000595:Amino Acid Sequence; D002455:Cell Division / Q000276:immunology; D000939:Epitopes / Q000032:analysis; D006510:Hepatitis B Antibodies / Q000096:biosynthesis; D006514:Hepatitis B Surface Antigens / Q000276:immunology*; D017325:Hepatitis B Vaccines / Q000276:immunology*; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000276:immunology*
chemical_list: D000939:Epitopes; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D010446:Peptide Fragments; D014614:Vaccines, Synthetic