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1w72
From Proteopedia
Crystal structure of HLA-A1:MAGE-A1 in complex with Fab-Hyb3
Structural highlights
Disease[B2MG_HUMAN] Defects in B2M are the cause of hypercatabolic hypoproteinemia (HYCATHYP) [MIM:241600]. Affected individuals show marked reduction in serum concentrations of immunoglobulin and albumin, probably due to rapid degradation.[1] Note=Beta-2-microglobulin may adopt the fibrillar configuration of amyloid in certain pathologic states. The capacity to assemble into amyloid fibrils is concentration dependent. Persistently high beta(2)-microglobulin serum levels lead to amyloidosis in patients on long-term hemodialysis.[2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] Function[1A01_HUMAN] Involved in the presentation of foreign antigens to the immune system. [MAGA1_HUMAN] May be involved in transcriptional regulation through interaction with SNW1 and recruiting histone deactelyase HDAC1. May inhibit notch intracellular domain (NICD) transactivation. May play a role in embryonal development and tumor transformation or aspects of tumor progression. Antigen recognized on a melanoma by autologous cytolytic T-lymphocytes.[15] [B2MG_HUMAN] Component of the class I major histocompatibility complex (MHC). Involved in the presentation of peptide antigens to the immune system. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedAntibodies with T cell receptor-like specificity possess a considerable diagnostic and therapeutic potential, but the structural basis of the interaction between an antibody and an histocompatibility antigen has so far not been determined. We present here the crystal structure (at 2.15 A resolution) of the recombinant, affinity-matured human antibody fragment Fab-Hyb3 bound to the tumor-associated human leukocyte antigen (HLA)/peptide complex HLA-A1.MAGE-A1. Fab-Hyb3 employs a diagonal docking mode resembling that of T cell receptors. However, other than these natural ligands, the antibody uses only four of its six complementarity-determining regions for direct interactions with the target. It recognizes the C-terminal half of the MAGE-A1 peptide, the HLA-A1 alpha1-helix, and N-terminal residues of the alpha2-helix, accompanied by a large tilting angle between the two types of molecules within the complex. Interestingly, only a single hydrogen bond between a peptide side chain and Fab-Hyb3 contributes to the interaction, but large buried surface areas with pronounced shape complementarity assure high affinity and specificity for MAGE-A1. The HLA-A1.MAGE-A1.antibody structure is discussed in comparison with those of natural ligands recognizing HLA.peptide complexes. A major histocompatibility complex-peptide-restricted antibody and t cell receptor molecules recognize their target by distinct binding modes: crystal structure of human leukocyte antigen (HLA)-A1-MAGE-A1 in complex with FAB-HYB3.,Hulsmeyer M, Chames P, Hillig RC, Stanfield RL, Held G, Coulie PG, Alings C, Wille G, Saenger W, Uchanska-Ziegler B, Hoogenboom HR, Ziegler A J Biol Chem. 2005 Jan 28;280(4):2972-80. Epub 2004 Nov 10. PMID:15537658[16] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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Categories: Human | Large Structures | Alings, C | Chames, P | Coulie, P G | Held, G | Hillig, R C | Hoogenboom, H R | Hulsmeyer, M | Saenger, W | Stanfield, R L | Uchanska-Ziegler, B | Wille, G | Ziegler, A | Hla/fab fragment | Human leucocyte antigen | Immune system | Mhc-i | Peptide-specific fab | Tcr-like binding
