Effect of IgG therapy on lymphocyte subpopulations in the peripheral blood of Kuwaiti women experiencing recurrent pregnancy loss

Abstract

Intravenously administered polyspecific IgG is being increasingly used as an immunomodulating therapy with controversial beneficial outcome. The aim of this study was to evaluate the effects of IgG infusion on peripheral T-cell subpopulations in women with recurrent pregnancy loss (RPL). Fifteen women with a history of three previous RPL between 6 and 22 weeks of gestation and positivity for the antiphospholipid antibody syndrome (APS) were randomized to one of two treatment groups: (a) an intravenous immunoglobulin therapy group (RPL-IVIg; 7 patients), 500 mg IVIg/kg/month and (b) a placebo-treated group given multivitamins (8 patients). Control groups comprised either normal pregnant women without APS (10 patients) or non-pregnant women. The T-cell markers were characterized using a monoclonal antibody panel including CD3, CD4, CD8, CD25, CD29, CD38, CD45RA, CD45RO, CD54 and HLA-DR. Analysis was performed with a two-color fluorescent-activated flow cytometer. In the first trimester, the percentage of CD4+CD25+, CD4+CD45RO+, CD8+HLA-DR+, and CD8+CD38+ populations were reduced in the multivitamin group compared to normal pregnant women (p < 0.05) while in the RPL-IVIg group only CD4+CD25+ cells were reduced (p < 0.05). By the second trimester, CD3+CD16+CD56+ was significantly higher in multivitamin- than in IVIg-treated women (p < 0.05). The percentage of CD4+HLA-DR+ was significantly higher in the two RPL groups compared to normal pregnant women (p < 0.05). IVIg therapy in women with RPL was associated with a significant reduction in CD3+CD16+CD56+ and CD4+CD25+. This may contribute to the suppression of immune-mediated processes contributing to premature abortion.