Immunology: β₂-glycoprotein i-dependent and -independent anticardiolipin antibodies in healthy pregnant women

The purpose of this study was to determine the association between β₂-glycoprotein I (β₂GPI)-dependent anticardiolipin antibodies (aCL) and β₂GPI-independent aCL and their respective relevance to adverse pregnancy outcomes. Therefore, we prospectively studied 210 normal pregnant women, utilizing a modified enzyme-linked immunosorbent assay method for β₂GPI-dependent and -independent aCL. Seven of the 210 pregnant women (3.3%) demonstrated evidence for β₂GPI-independent immunoglobulin G (IgG)-aCL. Two patients, who also appeared positive for β₂GPI-dependent IgG-aCL, were proven to be false positives. Amongst the 210 patients, not one was thus positive for β₂GPI-dependent aCL. Women with β₂GPI-independent aCL demonstrated no adverse pregnancy outcomes. These results suggest that the presence of β₂GPI-independent aCL is not associated with the presence of β2GPI-dependent aCL, though it may give rise to false positive results. Since the presence of β2GPI-independent aCL does not appear to be associated with adverse pregnancy outcomes, β₂GPI-dependent assays may represent better markers of miscarriage risk.