PF4 and autoimmune disease: Endotheliopathy-associated autoimmune diseases, such as SLE associated with positive anti-dsDNA, HIT-like thrombosis syndrome associated with anti-PF4 antibodies, APLA syndrome associated with positive anti-PL antibodies, or type 1 diabetes associated with positive anti-β islet cell antibodies, should be reexamined for their roles in the pathogenesis of autoantibody formation and clinical phenotypes, and particularly in light of the proven endothelial pathogenesis.