Maternal T cells and fetal survival

Increased T‐Cell Activation in Decidua Parietalis Compared to Decidua Basalis in Uncomplicated Human Term Pregnancy

“…In general, immune activation appears paradoxical at a site in which immunosuppression should predominate in order to guarantee maternal tolerance toward the fetus. It is suggested, however, that maternal T cells promote and contribute positively to placental growth and trophoblast invasion 36 . These studies imply that regionally activated T cells in the decidua basalis of early pregnancy may play an important role and that their balance with other leukocyte subsets may be essential to the maintenance of pregnancy.…”

Interplay between T helper type 1 and type 2 cytokines and soluble major histocompatibility complex molecules: a paradigm in pregnancy

“…T cells possess a central role not only in pregnancy but in the whole immune system. Elimination of T cells during pregnancy in murine experimental models results in increased levels of fetal abortion and significant reduction of placental growth 2,20 . More precisely, depletion of the CD8 + cell population from the maternal organism considerably reduces placental cell proliferation and phagocytosis, whereas elimination of CD4 + T cells results only in reduction of placental cell proliferation 21 .…”

Response

“…Regarding regulatory T cells (Treg), Aluvihare et al 3 showed that these cells play a key role in the homeostasis of normal pregnancy 4, and we in fact provided evidence that diminished Treg activity is seen in an abortion‐prone strain combination, and that abortion can be prevented by adoptive transfer of paternal‐antigen specific regulatory T cells 5; however, we never stated that this is the only mechanism operating to maintain the semiallogenic fetus in the mother. So we are not in conflict with Dr. Chaouat's statement.…”