title: Recognition of classical and heavy chain forms of HLA-B27 by leukocyte receptors.
abstract: As an MHC class I protein, the disease association of HLA-B27 with inflammatory arthritis has been widely assumed to imply a role for the T cell antigen receptor (TCR) in disease. However, in addition to their classical antigen-presenting role, HLA class I proteins are recognised by members of the killer immunoglobulin receptor (KIR) and leukocyte immunoglobulin-like receptor (LILR/ILT/LIR) families. Unusual properties of HLA-B27 include an ability of free heavy chains (FHC) to reach the cell surface in the absence of beta2m and to maintain their peptide-binding groove in vitro. This review describes immunomodulatory receptors that recognise HLA class I, and the recognition of HLA-B27 in both the classical beta2m-associated and beta2m-independent forms by members of the KIR and LILR families. Alternative recognition of different forms of HLA-B27 by leukocyte receptors could influence the function of cells from both innate and adaptive immune systems, and may indicate a role for various leukocyte populations in HLA-B27-associated inflammatory disease.
authors.affiliation: Department of Pathology, Tennis Court Road, Cambridge, CB2 1QP, UK. rla25@cam.ac.uk
authors.forename: Rachel L
authors.initials: RL
authors.lastname: Allen
authors.forename: John
authors.initials: J
authors.lastname: Trowsdale
mesh_terms: D000483:Alleles; D000818:Animals; D017951:Antigen Presentation / Q000276:immunology; D015703:Antigens, CD / Q000235:genetics / Q000276:immunology; D015796:HLA-B27 Antigen / Q000276:immunology*; D015395:Histocompatibility Antigens Class I / Q000235:genetics / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006801:Humans; D007113:Immunity, Innate / Q000276:immunology; D000075362:Leukocyte Immunoglobulin-like Receptor B1; D051379:Mice; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D011971:Receptors, Immunologic / Q000235:genetics / Q000276:immunology; D054340:Receptors, KIR; D025241:Spondylarthritis / Q000209:etiology / Q000276:immunology*; D013167:Spondylitis, Ankylosing / Q000209:etiology / Q000276:immunology*; D001613:beta 2-Microglobulin / Q000276:immunology
chemical_list: D015703:Antigens, CD; D015796:HLA-B27 Antigen; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; C105299:LILRB1 protein, human; D000075362:Leukocyte Immunoglobulin-like Receptor B1; D011948:Receptors, Antigen, T-Cell; D011971:Receptors, Immunologic; D054340:Receptors, KIR; D001613:beta 2-Microglobulin