title: Effects of end groups on the stimulatory capacity of minimal length T cell determinant peptides.
abstract: We studied the effect of end groups on the capacity of two closely related peptides to stimulate a human T cell clone. Using multipin peptide synthesis technology, we generated solution phase peptides with six combinations of end groups for each sequence. The end modifications examined were amino-terminal acetylation, carboxy-terminal methylamidation or the addition of a dipeptide containing a diketopiperazine ring. The response to the less stimulatory of the two peptide sequences was significantly increased by acetylation of the amino-terminus, a finding which was consistent at different peptide doses. Amino-terminal acetylation was found to be more significant in affecting responses than any of the carboxy-terminal modifications tested. The use of peptides with a diketopiperazine ring structure at the carboxy-terminus did not interfere with presentation and recognition of peptides and may enhance the effectiveness of peptides for T cell epitope scanning.
authors.affiliation: Coselco Mimotopes Pty. Ltd., Clayton, Victoria, Australia.
authors.forename: D A
authors.initials: DA
authors.lastname: Mutch
authors.forename: S J
authors.initials: SJ
authors.lastname: Rodda
authors.forename: M
authors.initials: M
authors.lastname: Benstead
authors.forename: R M
authors.initials: RM
authors.lastname: Valerio
authors.forename: H M
authors.initials: HM
authors.lastname: Geysen
mesh_terms: D000595:Amino Acid Sequence; D002999:Clone Cells / Q000276:immunology; D004306:Dose-Response Relationship, Immunologic; D006801:Humans; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000276:immunology*; D013329:Structure-Activity Relationship; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D010455:Peptides