title: Lack of KIR3DS1 binding to MHC class I Bw4 tetramers in complex with CD8+ T cell epitopes.
abstract: In HIV-1 infection, the synergistic association of a subset of Bw4 MHC class I molecules and the activating killer inhibitory receptor (KIR), KIR3DS1, with prolonged AIDS-free survival has been reported. As KIRs represent a diverse group of MHC class I receptors, we questioned whether Bw4 MHC class I molecules expressing isoleucine at position 80 (Bw4Ile80) and in complex with HIV-1-derived T cell epitopes represented KIR3DS1 ligands. MHC class I tetramers are powerful tools for the detection of T cell receptor-MHC class I interactions, and have recently been used to evaluate KIR-MHC class I binding ex vivo. Specifically, this approach has been successfully utilized to assess binding of Bw4 MHC class I tetramers to KIR3DL1, an inhibitory KIR and allele of KIR3DS1. In this study we generated a diverse panel of HIV-1-specific Bw4Ile80 MHC class I tetramers and tested its ability to bind transiently expressed KIR3DS1 on 293-T cells. Using flow cytometry analysis, the expression of KIR3DS1 on 293-T cells was confirmed by anti-FLAG BioM2 staining, prior to incubation with PE-conjugated MHC class I tetramers. Despite choosing a broad array of peptide epitopes and diverse Bw4Ile80 MHC class I molecules, we were unable to detect tetramer binding to KIR3DS1. We speculate that our negative finding may be a consequence of the MHC class I molecules and peptide epitopes chosen, but could also relate to key amino acid differences that distinguish KIR3DS1 from KIR3DL1.
authors.affiliation: MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford, OX3 9DS, UK. ggillesp@hammer.imm.ox.ac.uk
authors.forename: Geraldine M A
authors.initials: GM
authors.lastname: Gillespie
authors.forename: Arman
authors.initials: A
authors.lastname: Bashirova
authors.forename: Tao
authors.initials: T
authors.lastname: Dong
authors.forename: Daniel W
authors.initials: DW
authors.lastname: McVicar
authors.forename: Sarah L
authors.initials: SL
authors.lastname: Rowland-Jones
authors.forename: Mary
authors.initials: M
authors.lastname: Carrington
mesh_terms: D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000821:virology; D002460:Cell Line; D018604:Epitope Mapping / Q000379:methods*; D005434:Flow Cytometry; D015497:HIV-1 / Q000276:immunology*; D015235:HLA-B Antigens / Q000276:immunology*; D006801:Humans; D007694:Killer Cells, Natural / Q000821:virology; D008024:Ligands; D009842:Oligopeptides / Q000276:immunology*; D011971:Receptors, Immunologic / Q000276:immunology*; D054340:Receptors, KIR; D054341:Receptors, KIR3DL1; D054349:Receptors, KIR3DS1
chemical_list: D015235:HLA-B Antigens; C042388:HLA-Bw4 antigen; C515083:KIR3DL1 protein, human; D008024:Ligands; D009842:Oligopeptides; D011971:Receptors, Immunologic; D054340:Receptors, KIR; D054341:Receptors, KIR3DL1; D054349:Receptors, KIR3DS1