APS IgG stimulates monocytes to express TF activity,not via Fc receptor pathway / 中国免疫学杂志

ABSTRACT

Objective:To investigate whether the IgG from patients with antiphospholipid syndrome(APS) is capable of stimulating blood monocytes to express tissue factor(TF) activity and to explore the mechanisms possibly concerned.Methods:Freshly isolated peripheral blood monocytes were cultured in media containing purified APS IgG or normal IgG or RP-1 [a monoclonal anti-?_2 glucoprotein I(?-?_2GPI)antibody] and/or other agonists and the TF activity on monocytes was investigated by measuring factor Ⅶa-dependent generation of factor Xa.Results:APS IgG as well as RP-1 significantly increased monocytes TF activity,comparing to normal IgG;exogenous ?_2GPI enhanced the effects as the intact IgG molecule.Conclusion:That certain antiphospholipid antibodies,mainly anti-?_2GPI antibodies,induce monocytes TF activity in an antigen-specific manner,not via Fc receptor pathway,is contributed to the thrombotic diathesis in APS.