Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The antigenic determinant recognized by a HLA-DPw4-restricted human T cell clone specific for rabies virus was identified by using a vaccinia-rabies nonstructural phosphoprotein recombinant virus and synthetic peptides of the sequence of rabies nonstructural Ag. These peptides were selected on the basis of three models that predict T cell epitopes. The antigenic determinant recognized by the rabies virus-specific T cell clone contained a five-amino acid segment highly homologous to a sequence found in a hepatitis B surface Ag epitope that stimulates human T cells in the context of the HLA-DPw4. A preliminary model of DPw4-restricted T cell determinants is elaborated based on a hypothesis of how the 2 alpha-helical peptides may bind to this MHC molecule. Results are further discussed in the context of the usefulness in identifying DPw4-restricted T cell epitopes for the production of synthetic vaccines because this MHC class II molecule is found with high frequency in the population.
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PMID:Identification of a rabies virus T cell epitope on the basis of its similarity with a hepatitis B surface antigen peptide presented to T cells by the same MHC molecule (HLA-DPw4). 169 5

The antigenic sites for human T lymphocytes on hepatitis B surface Ag (HBsAg) were studied by using synthetic oligopeptides. T cell lines of the helper/inducer class, which were isolated from hepatitis B vaccine recipients, were found to react strongly and in an Ag-specific way with peptides corresponding to a sequence of 10 to 30 amino acids near the amino terminus of the HBsAg molecule. Cells with surface expression of the antigenic determinant contained in these synthetic peptides induced both proliferative and cytotoxic responses in the hepatitis B-specific T cells. The results indicate that amino acid residues 24-27 of HBsAg could be directly involved in this T cell determinant. Inhibition studies with mAb to MHC class II Ag and target cells from various HLA-typed individuals suggest that some T cell responses to this determinant of HBsAg might be restricted by the DPw4 molecule. However, the possibility exists that more than one of the MHC class II molecules could be involved as restricting elements of T cell responses to this synthetic peptide. In vivo experiments with synthetic peptides such as those described here are needed to demonstrate the possibility of enhancing HBsAg immune responses in some individuals.
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PMID:Recognition of hepatitis B surface antigen by human T lymphocytes. Proliferative and cytotoxic responses to a major antigenic determinant defined by synthetic peptides. 245 Jan 32

Human T cells that recognize a major epitope of the hepatitis B surface antigen were studied for their ability to react with antigen when presented by mouse fibroblasts that express class II products of the human major histocompatibility gene complex after gene transfection. L cells expressing HLA-DPw4, but not those expressing HLA-DR4 or HLA-DR7, induced strong proliferative responses of antigen-specific T cells to either hepatitis B surface antigen or the synthetic peptide S1d, which bears the immunodominant T-cell epitope. These results identified a genetic restriction element of human helper T-lymphocyte responses to a major antigenic determinant of hepatitis B virus and might be important in the design of subunit vaccines to this pathogen. Peptides that induce T-cell responses that are restricted by a frequently encountered major histocompatibility complex molecule in the general population such as DPw4 would be ideal candidates as subunit vaccines.
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PMID:Presentation of an immunodominant T-cell epitope of hepatitis B surface antigen by the HLA-DPw4 molecule. 246 81