Expression of the Thomsen-Friedenreich (TF) antigen in the human placenta

The Thomsen-Friedenreich (TF) antigen (or; more precisely, epitope; Gal bet a1-3GalNAc-) has been known for a long time as a pancarcinoma antigen. Here we report the immunohistochemical identification of this carbohydrate anti gen in the human placenta. Paraffin-embedded placental and decidual tissues of the first, second and third trimester were incubated with different mon oclonal antibodies (A78-G/A7 and HH8) directed against the TF-epitope and s tained with an immunohistochemistry system. We found a strong expression of the TF-epitope in the first trimester of pregnancy. In addition, we identi fied an expression of the TF-antigen in rite second trimester of pregnancy but only in a few cases a positive staining in the third trimester of pregn ancy.