title: T cell receptor-MHC class I peptide interactions: affinity, kinetics, and specificity.
abstract: The critical discriminatory event in the activation of T lymphocytes bearing alpha beta T cell receptors (TCRs) is their interaction with a molecular complex consisting of a peptide bound to a major histocompatibility complex (MHC)-encoded class I or class II molecule on the surface of an antigen-presenting cell. The kinetics of binding were measured of a purified TCR to molecular complexes of a purified soluble analog of the murine MHC class I molecule H-2Ld (sH-2Ld) and a synthetic octamer peptide p2CL in a direct, real-time assay based on surface plasmon resonance. The kinetic dissociation rate of the MHC-peptide complex from the TCR was rapid (2.6 x 10(-2) second-1, corresponding to a half-time for dissociation of approximately 27 seconds), and the kinetic association rate was 2.1 x 10(5) M-1 second-1. The equilibrium constant for dissociation was approximately 10(-7) M. These values indicate that TCRs must interact with a multivalent array of MHC-peptide complexes to trigger T cell signaling.
authors.affiliation: Molecular Biology Section, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892.
authors.forename: M
authors.initials: M
authors.lastname: Corr
authors.forename: A E
authors.initials: AE
authors.lastname: Slanetz
authors.forename: L F
authors.initials: LF
authors.lastname: Boyd
authors.forename: M T
authors.initials: MT
authors.lastname: Jelonek
authors.forename: S
authors.initials: S
authors.lastname: Khilko
authors.forename: B K
authors.initials: BK
authors.lastname: al-Ramadi
authors.forename: Y S
authors.initials: YS
authors.lastname: Kim
authors.forename: S E
authors.initials: SE
authors.lastname: Maher
authors.forename: A L
authors.initials: AL
authors.lastname: Bothwell
authors.forename: D H
authors.initials: DH
authors.lastname: Margulies
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015374:Biosensing Techniques; D006183:H-2 Antigens / Q000378:metabolism*; D064532:Histocompatibility Antigen H-2D; D007700:Kinetics; D008285:Major Histocompatibility Complex; D051379:Mice; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000378:metabolism*; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000378:metabolism*; D012995:Solubility
chemical_list: D006183:H-2 Antigens; D064532:Histocompatibility Antigen H-2D; D009842:Oligopeptides; D016693:Receptors, Antigen, T-Cell, alpha-beta