抄録
To assess the immunochemical characters of suppressor factor from human decidual cells (DC), serum free culture supernatants of DC were analyzed by high performance liquid chromatography (HPLC). Early pregnant decidual tissue was dispersed into a single cell by enzyme digestion using collagenase and DNase, and purified by Percoll® discontinuous density gradient method to avoid contamination of mononuclear lymphocytes and macrophages. 3×106/ml of DC were cultured in RPMI 1640 medium without fetal calf serum (FCS) for 48 hours at 37°C, and supernatants were harvested. The suppressor activity of culture supernatants were assessed by mixed lymphocyte reaction (MLR). Thirty two percent suppression was obtained by the addition of culture supernatants (50% volume) to MLR. To purify the suppressor factors in the supernatants, serum free culture supernatants were applied to gel filtration (HPLC) and the suppressor activity of each fraction was assessed by MLR. Fraction (Fr) 25 (between MW 43, 000 and 67, 000) displayed remarkable immunosuppressive activity, namely 46% inhibition in MLR. These results clearly demonstrated that DC secreted suppressor factor molecular weight of which was between 43, 000 and 67, 000, thereby protecting the fetus from maternal immunity.