3arb | pdb_00003arb
Ternary crystal structure of the NKT TCR-CD1d-alpha-galactosylceramide analogue-OCH
Structural highlights
Function[CD1D1_MOUSE] Antigen-presenting protein that binds self and non-self glycolipids and presents them to T-cell receptors on natural killer T-cells.[1] [2] [3] [B2MG_MOUSE] Component of the class I major histocompatibility complex (MHC). Involved in the presentation of peptide antigens to the immune system. Publication Abstract from PubMedNatural killer T (NKT) cells respond to a variety of CD1d-restricted antigens (Ags), although the basis for Ag discrimination by the NKT cell receptor (TCR) is unclear. Here we have described NKT TCR fine specificity against several closely related Ags, termed altered glycolipid ligands (AGLs), which differentially stimulate NKT cells. The structures of five ternary complexes all revealed similar docking. Acyl chain modifications did not affect the interaction, but reduced NKT cell proliferation, indicating an affect on Ag processing or presentation. Conversely, truncation of the phytosphingosine chain caused an induced fit mode of TCR binding that affected TCR affinity. Modifications in the glycosyl head group had a direct impact on the TCR interaction and associated cellular response, with ligand potency reflecting the t(1/2) life of the interaction. Accordingly, we have provided a molecular basis for understanding how modifications in AGLs can result in striking alterations in the cellular response of NKT cells. A Molecular Basis for the Exquisite CD1d-Restricted Antigen Specificity and Functional Responses of Natural Killer T Cells.,Wun KS, Cameron G, Patel O, Pang SS, Pellicci DG, Sullivan LC, Keshipeddy S, Young MH, Uldrich AP, Thakur MS, Richardson SK, Howell AR, Illarionov PA, Brooks AG, Besra GS, McCluskey J, Gapin L, Porcelli SA, Godfrey DI, Rossjohn J Immunity. 2011 Mar 25;34(3):327-39. Epub 2011 Mar 3. PMID:21376639[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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