NOS3 and autoimmune polyendocrinopathy: This essay provided a detailed overview of the thrombotic mechanisms of APS, including post-translational redox modifications of β2GPI, conformations of β2GPI, the “two hit” model, endothelial nitric oxide synthase, endothelial cells and monocytes, tissue factor, factor XI, platelets, annexin A5 anticoagulant shield and HCQ, complement and neutrophils, and disturbance of innate immunity, which were involved in the pathophysiology of APS.