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2f53
From Proteopedia
Directed Evolution of Human T-cell Receptor CDR2 residues by phage display dramatically enhances affinity for cognate peptide-MHC without apparent cross-reactivity
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[1A02_HUMAN] Involved in the presentation of foreign antigens to the immune system. [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 PubMedThe mammalian alpha/beta T cell receptor (TCR) repertoire plays a pivotal role in adaptive immunity by recognizing short, processed, peptide antigens bound in the context of a highly diverse family of cell-surface major histocompatibility complexes (pMHCs). Despite the extensive TCR-MHC interaction surface, peptide-independent cross-reactivity of native TCRs is generally avoided through cell-mediated selection of molecules with low inherent affinity for MHC. Here we show that, contrary to expectations, the germ line-encoded complementarity determining regions (CDRs) of human TCRs, namely the CDR2s, which appear to contact only the MHC surface and not the bound peptide, can be engineered to yield soluble low nanomolar affinity ligands that retain a surprisingly high degree of specificity for the cognate pMHC target. Structural investigation of one such CDR2 mutant implicates shape complementarity of the mutant CDR2 contact interfaces as being a key determinant of the increased affinity. Our results suggest that manipulation of germ line CDR2 loops may provide a useful route to the production of high-affinity TCRs with therapeutic and diagnostic potential. Directed evolution of human T cell receptor CDR2 residues by phage display dramatically enhances affinity for cognate peptide-MHC without increasing apparent cross-reactivity.,Dunn SM, Rizkallah PJ, Baston E, Mahon T, Cameron B, Moysey R, Gao F, Sami M, Boulter J, Li Y, Jakobsen BK Protein Sci. 2006 Apr;15(4):710-21. PMID:16600963[15] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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Categories: Human | Large Structures | Dunn, S M | Jakobsen, B K | Rizkallah, P J | Sami, M | Cdr2 | High affinity | Immune system | Mutant | Ny-eso-1 | Phage display | T-cell receptor
