Palmitic acid conjugation of a protein antigen enhances major histocompatibility complex class II-restricted presentation to T cells.
The effect on antigenicity of covalent attachment of lipid groups to a protein antigen was investigated. Coupling of palmitic acid to ovalbumin (OVA) enhanced major histocompatibility complex (MHC) class II-restricted presentation to most OVA-specific murine T-cell clones in vitro. The enhanced antigenicity of palmitoylated antigen was localized to the level of presentation of the synthetic peptide epitope, OVA 323-339. T-cell responses to palmitoylated antigen were more difficult to block with anti-MHC class II antibodies than responses to native antigen. However, T-cell proliferation to palmitoyl (p)-OVA and native (n)-OVA were blocked equally by anti-CD4 antibodies. Taken together, the results suggest that lipid conjugation of a protein antigen leads to the formation of a lipopeptide T-cell epitope with increased affinity of binding to MHC class II and/or T-cell receptor (TcR). These results have implications for the design of synthetic peptide vaccines.
Robinson
J H
JH
Department of Immunology, The Medical School, University of Newcastle upon Tyne, U.K.
Case
M C
MC
Brooks
C G
CG
D000276:Adjuvants, Immunologic; D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology*; D002455:Cell Division / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D010047:Ovalbumin / Q000276:immunology; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
D000276:Adjuvants, Immunologic; D000949:Histocompatibility Antigens Class II; D010169:Palmitic Acids; D019308:Palmitic Acid; D010047:Ovalbumin