Autoimmunity to Annexin A2 Predicts Mortality Among Hospitalised COVID-19 Patients

This study examined if COVID-19 patients have autoimmune antibodies to annexin A2, a protective protein expressed in the lung and other organs. Annexin A2 is critical for fibrinolysis, lung elasticity, cell membrane repair, and integrity of the pulmonary vasculature. Therefore, antagonism of annexin A2 may explain many of the clinical features of severe COVID-19 cases. This study analyzed patient plasma on hospital day 0 or 1 among 86 patients who were hospitalized for COVID-19. They measured anti-annexin A2 IgG antibodies and studied IgG antibodies directed against annexin A5 for comparison. Antibody levels were calculated using a plasma sample previously identified as a high responder for IgG autoantibodies. Using margins analysis, mortality rates were predicted based on anti-annexin A2 antibody levels.