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==Directed Evolution of Human T-cell Receptor CDR2 residues by phage display dramatically enhances affinity for cognate peptide-MHC without apparent cross-reactivity== | |||
<StructureSection load='2f53' size='340' side='right'caption='[[2f53]], [[Resolution|resolution]] 2.10Å' scene=''> | |||
| | == Structural highlights == | ||
<table><tr><td colspan='2'>[[2f53]] is a 5 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2F53 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2F53 FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.1Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene></td></tr> | |||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2f53 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2f53 OCA], [https://pdbe.org/2f53 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2f53 RCSB], [https://www.ebi.ac.uk/pdbsum/2f53 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2f53 ProSAT]</span></td></tr> | |||
</table> | |||
== Disease == | |||
[https://www.uniprot.org/uniprot/HLAA_HUMAN HLAA_HUMAN] Selection of immunotherapy in solid cancer;Birdshot chorioretinopathy;Prediction of phenytoin or carbamazepine toxicity. Alleles A*02:01 and A*24:02 are associated with increased susceptibility to diabetes mellitus, insulin-dependent (IDDM) (PubMed:22245737, PubMed:18802479, PubMed:16731854, PubMed:22522618). In a glucose-dependent way, allele A*02:01 may aberrantly present the signal peptide of preproinsulin (ALWGPDPAAA) on the surface of pancreatic beta cells to autoreactive CD8-positive T cells, potentially driving T-cell mediated cytotoxicity in pancreatic islets (PubMed:22245737, PubMed:18802479). Allele A*24:02 may present the signal peptide of preproinsulin (LWMRLLPLL) and contribute to acute pancreatic beta-cell destruction and early onset of IDDM (PubMed:16731854, PubMed:22522618).<ref>PMID:16731854</ref> <ref>PMID:18802479</ref> <ref>PMID:22245737</ref> <ref>PMID:22522618</ref> Allele A*03:01 is associated with increased susceptibility to multiple sclerosis (MS), an autoimmune disease of the central nervous system (PubMed:10746785). May contribute to the initiation phase of the disease by presenting myelin PLP1 self-peptide (KLIETYFSK) to autoreactive CD8-positive T cells capable of initiating the first autoimmune attacks (PubMed:18953350).<ref>PMID:10746785</ref> <ref>PMID:18953350</ref> Allele A*26:01 is associated with increased susceptibility to Behcet disease (BD) in the Northeast Asian population. Especially in the HLA-B*51-negative BD populations, HLA-A*26 is significantly associated with the onset of BD.<ref>PMID:30872678</ref> Allele A*29:02 is associated with increased susceptibility to birdshot chorioretinopathy (BSCR). May aberrantly present retinal autoantigens and induce autoimmune uveitis.<ref>PMID:1728143</ref> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/HLAA_HUMAN HLAA_HUMAN] Antigen-presenting major histocompatibility complex class I (MHCI) molecule. In complex with B2M/beta 2 microglobulin displays primarily viral and tumor-derived peptides on antigen-presenting cells for recognition by alpha-beta T cell receptor (TCR) on HLA-A-restricted CD8-positive T cells, guiding antigen-specific T cell immune response to eliminate infected or transformed cells (PubMed:2456340, PubMed:2784196, PubMed:1402688, PubMed:7504010, PubMed:9862734, PubMed:10449296, PubMed:12138174, PubMed:12393434, PubMed:15893615, PubMed:17189421, PubMed:19543285, PubMed:21498667, PubMed:24192765, PubMed:7694806, PubMed:24395804, PubMed:28250417). May also present self-peptides derived from the signal sequence of secreted or membrane proteins, although T cells specific for these peptides are usually inactivated to prevent autoreactivity (PubMed:25880248, PubMed:7506728, PubMed:7679507). Both the peptide and the MHC molecule are recognized by TCR, the peptide is responsible for the fine specificity of antigen recognition and MHC residues account for the MHC restriction of T cells (PubMed:12796775, PubMed:18275829, PubMed:19542454, PubMed:28250417). Typically presents intracellular peptide antigens of 8 to 13 amino acids that arise from cytosolic proteolysis via IFNG-induced immunoproteasome or via endopeptidase IDE/insulin-degrading enzyme (PubMed:17189421, PubMed:20364150, PubMed:17079320, PubMed:26929325, PubMed:27049119). Can bind different peptides containing allele-specific binding motifs, which are mainly defined by anchor residues at position 2 and 9 (PubMed:7504010, PubMed:9862734).<ref>PMID:10449296</ref> <ref>PMID:12138174</ref> <ref>PMID:12393434</ref> <ref>PMID:12796775</ref> <ref>PMID:1402688</ref> <ref>PMID:15893615</ref> <ref>PMID:17079320</ref> <ref>PMID:17189421</ref> <ref>PMID:18275829</ref> <ref>PMID:19542454</ref> <ref>PMID:19543285</ref> <ref>PMID:20364150</ref> <ref>PMID:21498667</ref> <ref>PMID:24192765</ref> <ref>PMID:24395804</ref> <ref>PMID:2456340</ref> <ref>PMID:25880248</ref> <ref>PMID:26929325</ref> <ref>PMID:27049119</ref> <ref>PMID:2784196</ref> <ref>PMID:28250417</ref> <ref>PMID:7504010</ref> <ref>PMID:7506728</ref> <ref>PMID:7679507</ref> <ref>PMID:7694806</ref> <ref>PMID:9862734</ref> Allele A*01:01: Presents a restricted peptide repertoire including viral epitopes derived from IAV NP/nucleoprotein (CTELKLSDY), IAV PB1/polymerase basic protein 1 (VSDGGPNLY), HAdV-11 capsid L3/hexon protein (LTDLGQNLLY), SARS-CoV-2 3a/ORF3a (FTSDYYQLY) as well as tumor peptide antigens including MAGE1 (EADPTGHSY), MAGEA3 (EVDPIGHLY) and WT1 (TSEKRPFMCAY), all having in common a canonical motif with a negatively charged Asp or Glu residue at position 3 and a Tyr anchor residue at the C-terminus (PubMed:1402688, PubMed:7504010, PubMed:17189421, PubMed:20364150, PubMed:25880248, PubMed:30530481, PubMed:19177349, PubMed:24395804, PubMed:26758806, PubMed:32887977). A number of HLA-A*01:01-restricted peptides carry a post-translational modification with oxidation and N-terminal acetylation being the most frequent (PubMed:25880248). Fails to present highly immunogenic peptides from the EBV latent antigens (PubMed:18779413).<ref>PMID:1402688</ref> <ref>PMID:17189421</ref> <ref>PMID:18779413</ref> <ref>PMID:19177349</ref> <ref>PMID:20364150</ref> <ref>PMID:24395804</ref> <ref>PMID:25880248</ref> <ref>PMID:26758806</ref> <ref>PMID:30530481</ref> <ref>PMID:7504010</ref> Allele A*02:01: A major allele in human populations, presents immunodominant viral epitopes derived from IAV M/matrix protein 1 (GILGFVFTL), HIV-1 env (TLTSCNTSV), HIV-1 gag-pol (ILKEPVHGV), HTLV-1 Tax (LLFGYPVYV), HBV C/core antigen (FLPSDFFPS), HCMV UL83/pp65 (NLVPMVATV) as well as tumor peptide antigens including MAGEA4 (GVYDGREHTV), WT1 (RMFPNAPYL) and CTAG1A/NY-ESO-1 (SLLMWITQC), all having in common hydrophobic amino acids at position 2 and at the C-terminal anchors.<ref>PMID:11502003</ref> <ref>PMID:12138174</ref> <ref>PMID:12796775</ref> <ref>PMID:17079320</ref> <ref>PMID:18275829</ref> <ref>PMID:19542454</ref> <ref>PMID:20619457</ref> <ref>PMID:22245737</ref> <ref>PMID:26929325</ref> <ref>PMID:2784196</ref> <ref>PMID:28250417</ref> <ref>PMID:7694806</ref> <ref>PMID:7935798</ref> <ref>PMID:8630735</ref> <ref>PMID:8805302</ref> <ref>PMID:8906788</ref> <ref>PMID:9177355</ref> Allele A*03:01: Presents viral epitopes derived from IAV NP (ILRGSVAHK), HIV-1 nef (QVPLRPMTYK), HIV-1 gag-pol (AIFQSSMTK), SARS-CoV-2 N/nucleoprotein (KTFPPTEPK) as well as tumor peptide antigens including PMEL (LIYRRRLMK), NODAL (HAYIQSLLK), TRP-2 (RMYNMVPFF), all having in common hydrophobic amino acids at position 2 and Lys or Arg anchor residues at the C-terminus (PubMed:7504010, PubMed:7679507, PubMed:9862734, PubMed:19543285, PubMed:21943705, PubMed:2456340, PubMed:32887977). May also display spliced peptides resulting from the ligation of two separate proteasomal cleavage products that are not contiguous in the parental protein (PubMed:27049119).<ref>PMID:19543285</ref> <ref>PMID:21943705</ref> <ref>PMID:2456340</ref> <ref>PMID:27049119</ref> <ref>PMID:7504010</ref> <ref>PMID:7679507</ref> <ref>PMID:9862734</ref> Allele A*11:01: Presents several immunodominant epitopes derived from HIV-1 gag-pol and HHV-4 EBNA4, containing the peptide motif with Val, Ile, Thr, Leu, Tyr or Phe at position 2 and Lys anchor residue at the C-terminus. Important in the control of HIV-1, EBV and HBV infections (PubMed:10449296). Presents an immunodominant epitope derived from SARS-CoV-2 N/nucleoprotein (KTFPPTEPK) (PubMed:32887977).<ref>PMID:10449296</ref> <ref>PMID:32887977</ref> Allele A*23:01: Interacts with natural killer (NK) cell receptor KIR3DL1 and may contribute to functional maturation of NK cells and self-nonself discrimination during innate immune response.<ref>PMID:17182537</ref> Allele A*24:02: Presents viral epitopes derived from HIV-1 nef (RYPLTFGWCF), EBV lytic- and latent-cycle antigens BRLF1 (TYPVLEEMF), BMLF1 (DYNFVKQLF) and LMP2 (IYVLVMLVL), SARS-CoV nucleocapsid/N (QFKDNVILL), as well as tumor peptide antigens including PRAME (LYVDSLFFL), all sharing a common signature motif, namely an aromatic residue Tyr or Phe at position 2 and a nonhydrophobic anchor residue Phe, Leu or Iso at the C-terminus (PubMed:9047241, PubMed:12393434, PubMed:24192765, PubMed:20844028). Interacts with natural killer (NK) cell receptor KIR3DL1 and may contribute to functional maturation of NK cells and self-nonself discrimination during innate immune response (PubMed:17182537, PubMed:18502829).<ref>PMID:12393434</ref> <ref>PMID:17182537</ref> <ref>PMID:18502829</ref> <ref>PMID:20844028</ref> <ref>PMID:24192765</ref> <ref>PMID:9047241</ref> Allele A*26:01: Presents several epitopes derived from HIV-1 gag-pol (EVIPMFSAL, ETKLGKAGY) and env (LVSDGGPNLY), carrying as anchor residues preferentially Glu at position 1, Val or Thr at position 2 and Tyr at the C-terminus.<ref>PMID:15893615</ref> Allele A*29:02: Presents peptides having a common motif, namely a Glu residue at position 2 and Tyr or Leu anchor residues at the C-terminus.<ref>PMID:8622959</ref> Allele A*32:01: Interacts with natural killer (NK) cell receptor KIR3DL1 and may contribute to functional maturation of NK cells and self-nonself discrimination during innate immune response.<ref>PMID:17182537</ref> Allele A*68:01: Presents viral epitopes derived from IAV NP (KTGGPIYKR) and HIV-1 tat (ITKGLGISYGR), having a common signature motif namely, Val or Thr at position 2 and positively charged residues Arg or Lys at the C-terminal anchor.<ref>PMID:1448153</ref> <ref>PMID:1448154</ref> <ref>PMID:2784196</ref> Allele A*74:01: Presents immunodominant HIV-1 epitopes derived from gag-pol (GQMVHQAISPR, QIYPGIKVR) and rev (RQIHSISER), carrying an aliphatic residue at position 2 and Arg anchor residue at the C-terminus. May contribute to viral load control in chronic HIV-1 infection.<ref>PMID:21498667</ref> | |||
== Evolutionary Conservation == | |||
[[Image:Consurf_key_small.gif|200px|right]] | |||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/f5/2f53_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2f53 ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The 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<ref>PMID:16600963</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 2f53" style="background-color:#fffaf0;"></div> | |||
== | ==See Also== | ||
*[[Beta-2 microglobulin 3D structures|Beta-2 microglobulin 3D structures]] | |||
*[[MHC 3D structures|MHC 3D structures]] | |||
*[[MHC I 3D structures|MHC I 3D structures]] | |||
*[[T-cell receptor 3D structures|T-cell receptor 3D structures]] | |||
== References == | |||
== | <references/> | ||
__TOC__ | |||
</StructureSection> | |||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: | [[Category: Large Structures]] | ||
[[Category: Dunn | [[Category: Dunn SM]] | ||
[[Category: Jakobsen | [[Category: Jakobsen BK]] | ||
[[Category: Rizkallah | [[Category: Rizkallah PJ]] | ||
[[Category: Sami | [[Category: Sami M]] | ||
Latest revision as of 10:43, 23 August 2023
Directed Evolution of Human T-cell Receptor CDR2 residues by phage display dramatically enhances affinity for cognate peptide-MHC without apparent cross-reactivityDirected Evolution of Human T-cell Receptor CDR2 residues by phage display dramatically enhances affinity for cognate peptide-MHC without apparent cross-reactivity
Structural highlights
DiseaseHLAA_HUMAN Selection of immunotherapy in solid cancer;Birdshot chorioretinopathy;Prediction of phenytoin or carbamazepine toxicity. Alleles A*02:01 and A*24:02 are associated with increased susceptibility to diabetes mellitus, insulin-dependent (IDDM) (PubMed:22245737, PubMed:18802479, PubMed:16731854, PubMed:22522618). In a glucose-dependent way, allele A*02:01 may aberrantly present the signal peptide of preproinsulin (ALWGPDPAAA) on the surface of pancreatic beta cells to autoreactive CD8-positive T cells, potentially driving T-cell mediated cytotoxicity in pancreatic islets (PubMed:22245737, PubMed:18802479). Allele A*24:02 may present the signal peptide of preproinsulin (LWMRLLPLL) and contribute to acute pancreatic beta-cell destruction and early onset of IDDM (PubMed:16731854, PubMed:22522618).[1] [2] [3] [4] Allele A*03:01 is associated with increased susceptibility to multiple sclerosis (MS), an autoimmune disease of the central nervous system (PubMed:10746785). May contribute to the initiation phase of the disease by presenting myelin PLP1 self-peptide (KLIETYFSK) to autoreactive CD8-positive T cells capable of initiating the first autoimmune attacks (PubMed:18953350).[5] [6] Allele A*26:01 is associated with increased susceptibility to Behcet disease (BD) in the Northeast Asian population. Especially in the HLA-B*51-negative BD populations, HLA-A*26 is significantly associated with the onset of BD.[7] Allele A*29:02 is associated with increased susceptibility to birdshot chorioretinopathy (BSCR). May aberrantly present retinal autoantigens and induce autoimmune uveitis.[8] FunctionHLAA_HUMAN Antigen-presenting major histocompatibility complex class I (MHCI) molecule. In complex with B2M/beta 2 microglobulin displays primarily viral and tumor-derived peptides on antigen-presenting cells for recognition by alpha-beta T cell receptor (TCR) on HLA-A-restricted CD8-positive T cells, guiding antigen-specific T cell immune response to eliminate infected or transformed cells (PubMed:2456340, PubMed:2784196, PubMed:1402688, PubMed:7504010, PubMed:9862734, PubMed:10449296, PubMed:12138174, PubMed:12393434, PubMed:15893615, PubMed:17189421, PubMed:19543285, PubMed:21498667, PubMed:24192765, PubMed:7694806, PubMed:24395804, PubMed:28250417). May also present self-peptides derived from the signal sequence of secreted or membrane proteins, although T cells specific for these peptides are usually inactivated to prevent autoreactivity (PubMed:25880248, PubMed:7506728, PubMed:7679507). Both the peptide and the MHC molecule are recognized by TCR, the peptide is responsible for the fine specificity of antigen recognition and MHC residues account for the MHC restriction of T cells (PubMed:12796775, PubMed:18275829, PubMed:19542454, PubMed:28250417). Typically presents intracellular peptide antigens of 8 to 13 amino acids that arise from cytosolic proteolysis via IFNG-induced immunoproteasome or via endopeptidase IDE/insulin-degrading enzyme (PubMed:17189421, PubMed:20364150, PubMed:17079320, PubMed:26929325, PubMed:27049119). Can bind different peptides containing allele-specific binding motifs, which are mainly defined by anchor residues at position 2 and 9 (PubMed:7504010, PubMed:9862734).[9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] Allele A*01:01: Presents a restricted peptide repertoire including viral epitopes derived from IAV NP/nucleoprotein (CTELKLSDY), IAV PB1/polymerase basic protein 1 (VSDGGPNLY), HAdV-11 capsid L3/hexon protein (LTDLGQNLLY), SARS-CoV-2 3a/ORF3a (FTSDYYQLY) as well as tumor peptide antigens including MAGE1 (EADPTGHSY), MAGEA3 (EVDPIGHLY) and WT1 (TSEKRPFMCAY), all having in common a canonical motif with a negatively charged Asp or Glu residue at position 3 and a Tyr anchor residue at the C-terminus (PubMed:1402688, PubMed:7504010, PubMed:17189421, PubMed:20364150, PubMed:25880248, PubMed:30530481, PubMed:19177349, PubMed:24395804, PubMed:26758806, PubMed:32887977). A number of HLA-A*01:01-restricted peptides carry a post-translational modification with oxidation and N-terminal acetylation being the most frequent (PubMed:25880248). Fails to present highly immunogenic peptides from the EBV latent antigens (PubMed:18779413).[35] [36] [37] [38] [39] [40] [41] [42] [43] [44] Allele A*02:01: A major allele in human populations, presents immunodominant viral epitopes derived from IAV M/matrix protein 1 (GILGFVFTL), HIV-1 env (TLTSCNTSV), HIV-1 gag-pol (ILKEPVHGV), HTLV-1 Tax (LLFGYPVYV), HBV C/core antigen (FLPSDFFPS), HCMV UL83/pp65 (NLVPMVATV) as well as tumor peptide antigens including MAGEA4 (GVYDGREHTV), WT1 (RMFPNAPYL) and CTAG1A/NY-ESO-1 (SLLMWITQC), all having in common hydrophobic amino acids at position 2 and at the C-terminal anchors.[45] [46] [47] [48] [49] [50] [51] [52] [53] [54] [55] [56] [57] [58] [59] [60] [61] Allele A*03:01: Presents viral epitopes derived from IAV NP (ILRGSVAHK), HIV-1 nef (QVPLRPMTYK), HIV-1 gag-pol (AIFQSSMTK), SARS-CoV-2 N/nucleoprotein (KTFPPTEPK) as well as tumor peptide antigens including PMEL (LIYRRRLMK), NODAL (HAYIQSLLK), TRP-2 (RMYNMVPFF), all having in common hydrophobic amino acids at position 2 and Lys or Arg anchor residues at the C-terminus (PubMed:7504010, PubMed:7679507, PubMed:9862734, PubMed:19543285, PubMed:21943705, PubMed:2456340, PubMed:32887977). May also display spliced peptides resulting from the ligation of two separate proteasomal cleavage products that are not contiguous in the parental protein (PubMed:27049119).[62] [63] [64] [65] [66] [67] [68] Allele A*11:01: Presents several immunodominant epitopes derived from HIV-1 gag-pol and HHV-4 EBNA4, containing the peptide motif with Val, Ile, Thr, Leu, Tyr or Phe at position 2 and Lys anchor residue at the C-terminus. Important in the control of HIV-1, EBV and HBV infections (PubMed:10449296). Presents an immunodominant epitope derived from SARS-CoV-2 N/nucleoprotein (KTFPPTEPK) (PubMed:32887977).[69] [70] Allele A*23:01: Interacts with natural killer (NK) cell receptor KIR3DL1 and may contribute to functional maturation of NK cells and self-nonself discrimination during innate immune response.[71] Allele A*24:02: Presents viral epitopes derived from HIV-1 nef (RYPLTFGWCF), EBV lytic- and latent-cycle antigens BRLF1 (TYPVLEEMF), BMLF1 (DYNFVKQLF) and LMP2 (IYVLVMLVL), SARS-CoV nucleocapsid/N (QFKDNVILL), as well as tumor peptide antigens including PRAME (LYVDSLFFL), all sharing a common signature motif, namely an aromatic residue Tyr or Phe at position 2 and a nonhydrophobic anchor residue Phe, Leu or Iso at the C-terminus (PubMed:9047241, PubMed:12393434, PubMed:24192765, PubMed:20844028). Interacts with natural killer (NK) cell receptor KIR3DL1 and may contribute to functional maturation of NK cells and self-nonself discrimination during innate immune response (PubMed:17182537, PubMed:18502829).[72] [73] [74] [75] [76] [77] Allele A*26:01: Presents several epitopes derived from HIV-1 gag-pol (EVIPMFSAL, ETKLGKAGY) and env (LVSDGGPNLY), carrying as anchor residues preferentially Glu at position 1, Val or Thr at position 2 and Tyr at the C-terminus.[78] Allele A*29:02: Presents peptides having a common motif, namely a Glu residue at position 2 and Tyr or Leu anchor residues at the C-terminus.[79] Allele A*32:01: Interacts with natural killer (NK) cell receptor KIR3DL1 and may contribute to functional maturation of NK cells and self-nonself discrimination during innate immune response.[80] Allele A*68:01: Presents viral epitopes derived from IAV NP (KTGGPIYKR) and HIV-1 tat (ITKGLGISYGR), having a common signature motif namely, Val or Thr at position 2 and positively charged residues Arg or Lys at the C-terminal anchor.[81] [82] [83] Allele A*74:01: Presents immunodominant HIV-1 epitopes derived from gag-pol (GQMVHQAISPR, QIYPGIKVR) and rev (RQIHSISER), carrying an aliphatic residue at position 2 and Arg anchor residue at the C-terminus. May contribute to viral load control in chronic HIV-1 infection.[84] 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[85] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also
References
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