Annexin A2 on lung epithelial cell surface is recognized by severe acute respiratory syndrome-associated coronavirus spike domain 2 antibodies.

摘要: Severe acute respiratory syndrome-associated coronavirus (SARS-CoV) infection causes lung failure characterized by atypical pneumonia. We previously showed that antibodies against SARS-CoV spike domain 2 (S2) in the patient sera can cross-react with human epithelial cells; however, autoantigen is not yet identified. In this study, we performed proteomic studies and identified several candidate autoantigens recognized SARS type II cell A549. Among proteins, annexin A2, which was mass spectrometry analysis had highest score Mascot data search, further investigated for its role as an autoantigen. By confocal microscopic observation, anti-S2 were co-localized on A549 cells both of them anti-annexin A2 antibodies. Anti-annexin bound to purified S2 immunoprecipitated from lysate a dose-dependent manner. Furthermore, increased surface expression raft-structure distribution present after stimulation SARS-induced cytokines interleukin-6 interferon-gamma. Cytokine binding capability cells. Together, upregulated SARS-associated cross-reactivity anti-SARS-CoV may have implications disease pathogenesis.