[Surface molecules on the trophoblast cells].

Normal pregnancies depend on successful implantation of the placenta in the uterus. The trophoblast forms the ultimate interface between foetal and maternal tissue. It seems to lack the foreign antigens required to induce immunological rejection reactions in the mother. Therefore a successful pregnancy probably does not depend on the production of blocking antibodies to protect the foetus from maternal cytotoxic T-cells. Non-MHC-molecules may play a role in placentation. Trophoblast cells and cancer cells have several properties in common.