Pregnancy-induced alterations in graft-versus-host responsiveness of uterine-draining and peripheral lymph node cells toward fetal alloantigens.

The popliteal lymph node assay was used to assess the effects of allogeneic pregnancy on the graft-versus-host (GVH) responsiveness of maternal uterine-draining and peripheral lymph node cells toward fetal alloantigens. These two cell populations were obtained from three groups of female mice: BALB/c virgins, BALB/c females 13 days pregnant by C3H males, and BALB/c females 13 days pregnant by BALB/c males. Recipients of the donor cells were (BALB/c x C3H)F1 and (BALB/c x C57)F1 hybrids. Uterine-draining lymph node (UDLN) cells at day 13 of an allogeneic pregnancy were specifically hyporesponsive toward fetal alloantigens compared to peripheral lymph node cells from the same donors. There was no difference in responsiveness between uterine-draining and peripheral lymph node cells in virgin or syngeneically pregnant mice. Therefore, the local nodes draining the uteri of primigravid mice carrying allogeneic fetuses, but not syngeneic fetuses, showed a specific decrease in GVH activity toward fetal alloantigens.