title: Ii-Key/MHC class II epitope hybrid peptide vaccines for HIV.
abstract: The Ii-Key/MHC class II epitope hybrid acts on MHC class II molecules to facilitate replacement of antigenic peptides with the epitope tethered to the Ii-Key motif. Hybrid peptides linking an immunoregulatory segment of the Ii protein (Ii-Key peptide) through a polymethylene bridge to MHC class II epitopes of HIV gp160 or gag are potent vaccines to elicit CD4(+) T cell responses. More potent responses to two MHC class II epitopes, HIV gp160(843-852) or HIV gag(279-292), occurred in mice immunized with Ii-Key hybrid peptides than with epitope-only peptides, as measured in IL-4 and IFN-gamma ELISPOT assays of splenic lymphocytes stimulated in vitro by epitope-only peptides. Both the number of responding cells and cytokine output per cell were increased. The Ii-Key/MHC class II epitope hybrid acts on MHC class II molecules to facilitate replacement of antigenic peptides with the epitope tethered to the Ii-Key motif. Such antigenic peptide constructs create opportunities to enhance greatly Th1 or Th2 responses to MHC class II epitopes for therapeutic purposes.
mesh_terms: D016915:AIDS Vaccines / Q000276:immunology*; D000818:Animals; D000944:Antigens, Differentiation, B-Lymphocyte / Q000235:genetics*; D000939:Epitopes / Q000235:genetics*; D005802:Genes, MHC Class II / Q000235:genetics*; D016655:HIV Core Protein p24 / Q000235:genetics / Q000276:immunology; D019302:HIV Envelope Protein gp160 / Q000235:genetics / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D007114:Immunization; D051379:Mice; D008809:Mice, Inbred C3H; D013154:Spleen / Q000166:cytology / Q000276:immunology; D022223:Vaccines, Subunit / Q000276:immunology
chemical_list: D016915:AIDS Vaccines; D000944:Antigens, Differentiation, B-Lymphocyte; D000939:Epitopes; D016655:HIV Core Protein p24; D019302:HIV Envelope Protein gp160; D000949:Histocompatibility Antigens Class II; D022223:Vaccines, Subunit; C045084:invariant chain