|Budget Amount *help
¥14,400,000 (Direct Cost: ¥14,400,000)
Fiscal Year 2002: ¥6,600,000 (Direct Cost: ¥6,600,000)
Fiscal Year 2001: ¥7,800,000 (Direct Cost: ¥7,800,000)
The antiphospholipid syndrome (APS) is defined by predominant clinical features of venous and arterial thrombosis, recurrent pregnancy loss, and thrombocytopenia in the presence of antiphospholipid antibodies, namely anticardiolipin antibodies (aCL), lupus anticoagulant and antiprothrombin antibodies. In 1990, we reported that a 50 kDa plasma/serum cofactor, β2-glycoprotein I (β2GPI), is required for the aCL binding to the solid phase CL.
Genetically determined structural variation in the β2GPI molecule has been identified by isoelectric focusing and by immunoblotting. Recently, the molecular basis of β2GPI protein polymorphism (codons at 88, 247, 306, and 316) and its distribution in large U.S. populations, non-Hispanic whites, Hispanics, Blacks and/or Japanese has been reported. β2GPI exon 7 polymorphism leads to a valine-leucine amino acid exchange at position 247 in domain 5 of β2GPI, between the phospholipids binding site and the cryptic site of the epitopes for anti-β2GPI antibodies. The β2GPI polymorphism, valine/leucine^<247>, is correlated with anti-β2GPI antibody production in patients with APS, and valine^<247> may be important in the formation of β2GPI antigenicity.