Fine specificity of HLA-B27 cellular allorecognition. HLA-B27f is a functional variant distinguishable by cytolytic T cell clones.
Three HLA-B27 allospecific cytolytic T lymphocyte (CTL) clones were isolated by limiting dilution of HLA-B27-negative responder cells stimulated with HLA-B27.1-positive lymphoblastoid cells. These clones displayed three distinct reaction patterns when tested for their lytic ability against target cells expressing various structurally defined HLA-B27 subtypes. One of the clones was specific for HLA-B27.1; a second CTL clone reacted only with B27.1 and, less efficiently, with B27.2; the third clone recognized both B27.1 and B27f targets but not cells expressing any other B27 subtype. These results indicate that HLA-B27f is a functional variant amenable to differential recognition by alloreactive CTL. A correlation of the structure of the HLA-B27 subtypes with the reactivity of these clones revealed that multiple B27-specific alloreactive CTL are activated against epitopes of the HLA-B27.1 molecule sharing common structural features. This illustrates the complexity and fine specificity of the allogeneic CTL response against class I HLA antigens and suggests that their immunodominant regions are those which are capable of eliciting a diverse polyclonal response against each of these regions, rather than inducing the selective expansion of a single T cell clone.
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology; D002999:Clone Cells / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D000939:Epitopes / Q000276:immunology; D006680:HLA Antigens / Q000276:immunology*; D015796:HLA-B27 Antigen; D006801:Humans; D007959:Lymphocyte Culture Test, Mixed; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000939:Epitopes; D006680:HLA Antigens; D015796:HLA-B27 Antigen