Transforming growth factor-β1, -β2, -β3 and their type I and II receptors in human term placenta

Expression of transforming growth factor (TGF)-beta(3) as well as cellular localization of TGF-beta receptors has not been demonstrated in placenta. TGF-beta receptor type I (RI) and type II (RII) are required to transmit TGF-beta signals, therefore the determination of cells expressing both receptors in concert is necessary to identify target cells for TGF-beta. We investigated presence and localization of IGF-beta s and their receptors (RI, RII) in human term placenta using reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. RT-PCR showed that messenger RNA for TGF-beta(1), -beta(2), -beta(3), and RI and RII is present in human term placenta. We found intense staining for all TGF-beta isoform and receptor proteins in the syncytiotrophoblastic layer, chorionic plate, and in cells of the extravillous trophoblasts using immunohistochemistry. The simultaneous expression of ligands and their receptors support the hypothesis that TGF-beta may play an important role in regulating growth, differentiation, and function of the human placenta. Copyright (C) 2000 S. Karger AG, Basel.