Binding and internalization of immunoglobulin G by cultured human trophoblast

A preparation consisting of a high percentage of trophoblasts can be obtained by centrifuging a mixture of cell types from trypsinized term placental villi on a discontinuous gradient of Percoll. When cultured these cells maintain trophoblast characteristics as judged by immunocytochemical markers and beta-human chorionic gonadotrophin production. Incubation of cells with labelled human immunoglobulin G demonstrated their ability to bind and internalize this macromolecule in a time- and temperature-dependent manner.