[Fetomaternal immune reaction in normal and pathologic pregnancies]

Pregnancy-specific diseases such as pre-eclampsia/eclampsia and intrauterine growth retardation do certainly influence the feto-maternal immunological links; this effect may be primary or secondary. In vitro methods to measure quantitatively the maternal cellular immune response and its sensitivity to humeral serum factors are discussed. Trophoblast cells grown in macro- and microcultures under standardized conditions were exposed to the cytotoxic effect of a suspension of maternal lymphocytes derived from peripheral venous blood; the concentration of lymphocytes was titrated. In a second titration series we tested the influence of maternal serum on the lymphocytotoxic effect; trophoblast and lymphocyte cell numbers were kept constant. The results give some evidence that in the absence of maternal serum the lymphocytotoxicity is diminished in cases with poor fetal growth or with pre-eclampsia/eclampsia, if compared with the conditions found in cases of normal term pregnancies. If, however, maternal serum was present, the known anticytotoxic effect of the serum became only evident in the normal term controls, whereas the cytotoxicity increased with rising serum concentrations in cultures derived from cases with intrauterine growth retardation or pre-eclampsia/eclampsia. One possible explanation would be the presence of cytotoxic serum factors in those cases. In the discussion the different aspects of feto-maternal immune relationship in healthy subjects are analysed and an attempt is made to correlate the findings of different authors. It is most likely that the maternal immune responses (directed specifically and non-specifically against fetal antigens) do vary continuously in pregnancy.