β2-Glycoprotein I/HLA class II complexes are novel autoantigens in antiphospholipid syndrome

β2-Glycoprotein I/HLA class II complexes are novel autoantigens in antiphospholipid syndrome.

Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by thrombosis and/or pregnancy complications. β2-glycoprotein I (β2GPI) complexed with phospholipid is recognized as a major target for autoantibodies in APS; however, less than half the patients with clinical manifestations of APS possess autoantibodies against the complexes. Therefore, the range of autoantigens involved i...

Structural Changes in β2-Glycoprotein I and the Antiphospholipid Syndrome

Isolated IgA Anti-β2 Glycoprotein I Antibodies in Patients with Clinical Criteria for Antiphospholipid Syndrome

Seronegative antiphospholipid syndrome (SNAPS) is an autoimmune disease present in patients with clinical manifestations highly suggestive of Antiphospholipid Syndrome (APS) but with persistently negative consensus antiphospholipid antibodies (a-PL). IgA anti-β 2 Glycoprotein I (aB2-GPI) antibodies are associated with APS. However, they are not currently considered to be laboratory criteria due...

A novel pathway for human endothelial cell activation by antiphospholipid/anti-β2 glycoprotein I antibodies.

Antiphospholipid Abs (APLAs) are associated with thrombosis and recurrent fetal loss. These Abs are primarily directed against phospholipid-binding proteins, particularly β(2)GPI, and activate endothelial cells (ECs) in a β(2)GPI-dependent manner after binding of β(2)GPI to EC annexin A2. Because annexin A2 is not a transmembrane protein, the mechanisms of APLA/anti-β(2)GPI Ab-mediated EC activ...

Revisiting Beta 2 Glycoprotein I, the Major Autoantigen in the Antiphospholipid Syndrome

Beta 2 glycoprotein I (β2GPI) is a single chain 50 kDa highly glycosylated glycoprotein at an approximate concentration of 4 μM in cells. The abundance of this protein in plasma and its high state of preservation indicate the important role of this protein in mammalian. In addition, β2GPI has a particular structure in the fifth domain, and is categorized as the major antigen recognized by autoa...