Antigen-specific immune reactions by expanded CD8 T cell clones from HLA-B*27-positive patients with spondyloarthritis.

Spondyloarthritis (SpA) is a chronic inflammatory disease that is tightly linked to HLA-B*27 but the pathophysiological basis of this link is still unknown. It is discussed whether either the instability of HLA-B*27 molecules triggers predominantly innate immune reactions or yet unknown antigenic peptides presented by HLA-B*27 induce adaptive autoimmune reactions by CD8 T cells. To analyze the pathogenesis of SpA, we here investigated the T cell receptor (TCR) usage and whole transcriptomes of CD8 single cells from synovial fluid of HLA-B*27-positive SpA patients and HLA-B*27-negative controls.