title: Multiple column synthesis of a library of T-cell stimulating Tn-antigenic glycopeptide analogues for the molecular characterization of T-cell-glycan specificity.
abstract: A series of peptides and glycopeptides derived by amino acid and glycosyl amino acid scans through the self peptide from CBA/J mouse haemoglobin Hb (67-76). VITAFNEGLK, was synthesized by multiple column peptide synthesis (MCPS). Investigation of glycopeptide binding to the mouse major histocompatibility class II molecule Ek showed that glycans in position 72 did not interfere with the binding to Ek. Immunization experiments revealed that glycopeptides with the glycan in position 72 were immunogenic. Therefore a series of N-linked and O-linked glycopeptides with the glycan attached in the position 72 either to serine, threonine or asparagine was synthesized by MCPS. The glycan structure was furthermore varied with respect to monosaccharide component, size of oligosaccharide, anomer configuration and stereochemistry of essential hydroxyl groups in order to investigate the specificity of the interaction with the T-cell receptor. Easy synthesis of ready to use Ser and Thr building blocks corresponding to mucin core 1, the Tn-antigen and its beta-anomer were developed using trichloroacetimidates as glycosyl donors and reduction with in situ acetylation of the azide containing glycosylation products. Synthesis of an alpha-linked GlcNAc-Thr building block was achieved by glycosylation of Fmoc-Thr-OPip with 2-azido-2-deoxy-3,4,6-tri-O-acetyl-D-glycopyranosyl trichloroacetimidate as a glycosyl donor. Other building blocks were obtained by previously described procedures.
authors.affiliation: Carlsberg Laboratory, Department of Chemistry, Copenhagen, Denmark.
authors.forename: K
authors.initials: K
authors.lastname: Frische
authors.forename: M
authors.initials: M
authors.lastname: Meldal
authors.forename: O
authors.initials: O
authors.lastname: Werdelin
authors.forename: S
authors.initials: S
authors.lastname: Mouritsen
authors.forename: T
authors.initials: T
authors.lastname: Jensen
authors.forename: L
authors.initials: L
authors.lastname: Galli-Stampino
authors.forename: K
authors.initials: K
authors.lastname: Bock
mesh_terms: D000818:Animals; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D000939:Epitopes / Q000737:chemistry*; D006020:Glycopeptides / Q000138:chemical synthesis* / Q000737:chemistry* / Q000276:immunology; D051379:Mice; D008808:Mice, Inbred CBA; D019151:Peptide Library; D011134:Polysaccharides / Q000737:chemistry / Q000276:immunology*; D015202:Protein Engineering; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate; D000939:Epitopes; D006020:Glycopeptides; D019151:Peptide Library; D011134:Polysaccharides; C040286:Tn antigen