| Abstract: | PROBLEM : Anticardiolipin antibodies (aCL) are commonly associated with recurrent pregnancy loss, though the mechanism is uncertain. Some investigators have indicated that aCL may be directed at a complex made up of cardiolipin and a blood anticoagulant, β2-glycoprotein I (β2GPI). We therefore investigated the effects of β2GPI-dependent aCL IgG enriched fractions, isolated from sera of patients with pregnancy losses, on blood coagulation. METHOD : β2GPI-dependent aCL were prepared from sera of three women with second trimester pregnancy losses, by cardiolipin affinity column chromography, following by anti-β2GPI affinity column chromatography. The effects of β2GPI and β2GPI-dependent aCL on the activation of factor X in vitro were examined. RESULTS : β2GPI inhibited the activation of factor X and β2GPI-dependent aCL blocked this inhibitory effect in a dose dependent manner. CONCLUSION : These results imply the possibility of β2GPI-dependent aCL induce hypercoagulation or thrombus by blocking the inhibitory effect of β2GPI on activation of factor X, which may result in pregnancy loss. |
