title: Quantitative determination of TCR cross-reactivity using peptide libraries and protein databases.
abstract: A single T cell clone can be activated by many different peptides in the context of a particular HLA molecule. To quantify the number of peptides that can be recognized by a CD4(+) T cell clone, we screened a one-bead-one-peptide synthetic peptide library and a protein database for peptides that stimulate an HLA-DR3-restricted, human glutamic acid decarboxylase (GAD65)-reactive CD4(+) T cell clone. Both the library screening and the database analysis indicated that this T cell clone is able to recognize approximately 10(6) 11-mer peptides at low nanomolar concentration. Furthermore, we determined that the frequency of cross-reactivity increased only 1.5-3 times when the peptide concentration increased 10 times, in the range of 0.01 - 1 microM. These data imply that there is a considerable potential for T cell cross-reactivity and are useful for studies on the role of molecular mimicry in the etiology of T cell-mediated disease.
authors.affiliation: Department of Immunohematology and Blood Bank, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: H S
authors.initials: HS
authors.lastname: Hiemstra
authors.forename: P A
authors.initials: PA
authors.lastname: van Veelen
authors.forename: S J
authors.initials: SJ
authors.lastname: Willemen
authors.forename: W E
authors.initials: WE
authors.lastname: Benckhuijsen
authors.forename: A
authors.initials: A
authors.lastname: Geluk
authors.forename: R R
authors.initials: RR
authors.lastname: de Vries
authors.forename: B O
authors.initials: BO
authors.lastname: Roep
authors.forename: J W
authors.initials: JW
authors.lastname: Drijfhout
mesh_terms: D000595:Amino Acid Sequence; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002999:Clone Cells; D003429:Cross Reactions; D016208:Databases, Factual; D005968:Glutamate Decarboxylase / Q000276:immunology; D015803:HLA-DR3 Antigen / Q000276:immunology; D006801:Humans; D008213:Lymphocyte Activation; D018716:Molecular Mimicry; D019151:Peptide Library; D011506:Proteins / Q000737:chemistry / Q000276:immunology; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*
chemical_list: D015803:HLA-DR3 Antigen; D019151:Peptide Library; D011506:Proteins; D011948:Receptors, Antigen, T-Cell; D005968:Glutamate Decarboxylase