In one study of 54 COVID-19-hospitalized patients (34 in the intensive care unit (ICU) and 20 in non-ICU), 74.1% were positive for aPL antibodies, with 60% testing positive for lupus anti-coagulant (La), 18.5 % for IgM aCL, 14.8% for IgM anti-β2GPI and 24% for IgA anti-β2GPI [219]. Here, CD40LG is linked to systemic lupus erythematosus.