[Immune cells on the IUD].

Cells isolated on the surface of just removed IUD "DANA" were characterized by means of monoclonal antibodies and the avidin-biotin method. Activated macrophages with the membrane sign CD 14 and transferrin receptors (25-72%) and B lymphocytes producing IgA and IgG (14-56%) contained strong transplantation antigens class II. By these glycoproteins macrophages and B cells are able to differentiate alie and thus also paternal antigens. The presence of these cells in the uterus may be the stimulus for triggering an aggressive cytotoxic reaction against the blastocyst and explains the contraceptive action of intrauterine devices.