Detection of macrophages and the characterization of Fc receptor-bearing cells in the mouse decidua, placenta and yolk sac using the macrophage-specific monoclonal antibody F4/80.

A mouse macrophage-specific rat monoclonal antibody, F4/80, has been used to detect directly macrophages in short term cultures of mouse decidua, fetal placenta and yolk sac and to investigate the identity of Fc receptor (FcR) bearing cells in these tissues. We find that a significant proportion of FcR positive cells in decidual, placental and yolk sac tissues are macrophages as defined by the expression of the macrophage marker, F4/80 antigen. Macrophages may act as immunocompetent cells near to the maternal-fetal interface and play a significant role in the mechanism of the transfer of passive immunity from mother to fetus across the mouse yolk sac.