Cross-Reactive T Cell Clones from Unrelated Individuals Reveal Similarities in Peptide Presentation between HLA-B27 and HLA-DR2 1

Abstract

HLA-B27- responder cells were stimulated in vitro with B*2705+ lymphoblastoid cell lines and alloreactive CTL clones were obtained by limiting dilution. Of the CD3+CD4-CD8+ HLA-B27-specific CTL clones obtained, two of them, possessing the same TCR, cross-reacted with HLA-DR2. The fine specificity of these CTL was established with HLA-B27 and HLA-DR2 subtypes. They recognized the B*2701 to B*2706 subtypes, but only DR2Dw2. Lysis of DR2+ target cells was specifically inhibited by anti-CD3, anti-class II, and anti-DR mAb, but not with an anti-CD8 antibody. The monoclonal nature of the cross-reaction was established by the mutual inhibition of HLA-B27 and DR2Dw2 cells in cold target competition ..