Evaluation of a monoclonal antibody, BC-1, which identifies an antigen expressed on the surface membrane of human extravillous trophoblast.

This paper describes a new Mab BC-1 which is directed at a cell surface antigen expressed by extravillous cytotrophoblast and not by villous cytotrophoblast, so it is useful for distinguishing between the two populations. The antigen recognised by BC-1 is trypsin-resistant, which allows it to be used for flow cytometric analysis of living trophoblast isolated by enzymic disaggregation. However, BC-1 is not trophoblast-specific but cross-reacts with some other tissues, in particular endothelial cells and peripheral blood monocytes. The nature of this antigen has not been established.