Dons'koj B. Antiphospholipid antibodies and anti-idiotypic regulation.

The antigenic specificity of antiphospholipid antibodies (APA) is a matter of intensive investigation. Difference in the reported involvement of APA in clinical manifestation may be due, in part, to the polyclonal nature of these antibodies and the use of serum and serum fractions for analysis. To circumvent this issue, we generated mouse monoclonal APA and compared their antigen binding patterns and conditions of this reaction. High frequency of antiphospholipid antibodies (APA) has been observed in patients with systemic autoimmune disease as well as in women undergoing IVF. . We had showed that APA in SLE patients are generally b2GP1-dependent. APA in IVF and HVHB patients was generally b2GP1-independent. APA in SLE patients was cofactor-dependent in 80% cases and only 28% in women undergoing IVF. This data can explain absence of thrombotic complication in APA positive IVF patient, because its complications associated rather with cofactor-dependent APA. It also can explain a lot of controversial results about significance of APA on IVF result. Antiphospholipid antibodies (АPА) and anti-idiotypic antiphospholipid antibodies (AiAPA) were also studied in women undergoing IVF. АPА (IgG аCL, аPS, аPE, аPA, аPG, аPC) levels in serum has been defined. Sera IgG fraction was also examined for the presence of AiAPA by three different methods: indirect binding of AiAPA in ELISA with mouse monoclonal cofactor-independent APA (mAPA), AiAPA neutralization of binding of human affinity isolated APA and mAPA with phospholipids. We had found significant difference in levels of AiAPA between APA+ and APA- women undergoing IVF. In APA+ women undergoing IVF, the mean level of AiAPA was lower than in APA- women among the same group (p<0,05). IvIg infusion significant decrease the APA as well as increase the AiAPA level in APA+ women undergoing IVF. Result of this study confirmed possibility of AiAPA participation in down regulation of cofactor-independent APA production in women undergoing IVF.