Immunological detection of cell surface galactosyltransferase in preimplantation mouse embryos

Presence of cell surface galactosyltransferase was surveyed in preimplantation mouse embryos by indirect immunofluorescence staining using an affinity-purified antibody against galactosyltransferase from human milk. Distinct fluorescence staining was observed in embryos ranging from late 8-cell stage to early blastocysts, while the embryos at other stages were stained only weakly. The cell surface enzyme was also present in F9 embryonal carcinoma cells, in a fraction of bone marrow cells of the mouse, and in a few percent of testicular sperm.