Rat anti-Mouse stage-specific embryonic antigen-3 monoclonal antibody for FC. SSEA3 is a globoseries carbohydrate antigen present on both cell surface glycolipids and glycopeptides. It is found on the surface of mouse oocytes, becoming restricted to the intracellular mass of the early blastocyst and then to the primitive endoderm. It is present on the surface of human teratocarcinoma cells (EC), embryonic germ cells (EG) and embryonic stem cells (ES) but not mouse undifferentiated mouse cells of these types. SSEA3 expression decreases as human EC, ES and EG cells differentiate but increases on differentiation of mouse EC, ES and EG cells. It is also found on the surface of mouse erythrocytes.