The Accumulation of a Novel Type of Suppressor Cell in the Uterus of the Allopregnant Mice During Successful Pregnancy

Abstract

<p>Successful pregnancy involves the accumulation of non-T, FcR-positive cells at the implantation sites of syngenic allogeneic of CTL (cytotoxic T cells) in vitro and in vivo by blocking the response to interleukin 2. It has been shown that xenogeneic embryos can be gestated successfully if enveloped in the trophoblast genotypically compatible with the pseudopregnant recipient (Rossant et al., 1982, J. Emb. Exp. Morph., 69: 141). We have recently demonstarted that the trophoblast plays a critical role in the localization of the deciduaassociated suppressor cell in pseudopregnant mice. We now show that supernatants genereated from trophoblast cell cultures and day 9.5 ectoplacental cone cultures were successful in the recruitment of the non-T, granulated suppressor cell which sediments at 3 ± 0.05 mm/h. These results suggest that the trophoblast elaborates a factor(s) which plays an important role in the accumulation of the deciduaassociated suppressor cells in the decidue which may protect the anti-genic fetus from maternal immue rejection.</p>