Transforming growth factor-ß receptor profiles of human and murine embryonic palate mesenchymal cells
Cell signalling in the developing mammalian palate appears to involve various growth factors and hormones. An important developmental role for the transforming growth factor-ß (TGF-ß) class of growth factors is suggested by the immunolocalization of TGF-ß1 in the palate during its ontogeny. This study examined the effects of TGF-ß stimulation of, as well as TGF-ß receptor profiles in, murine embryonic palate mesenchymal (MEPM) and human embryonic palate mesenchymal (HEPM) cells. Results showed that TGF-ß1 (1 ng/ml) stimulated proliferation of HEPM cells and inhibited proliferation of MEPM cells in a dose-dependent manner. The time course of 125I-TGF-ß1 binding to specific receptors was determined by incubating cells in the presence of 170 pM125I-TGF-ß1 for up to 4 h. In both cell types, at 37 °C, the binding of 125I-TGF-ß decreased linearly over 4 h, while at 4 °C, binding increased with time of incubation. Incubation of both cell types at 4 °C for 4 h, with increasing concentrations of 125I-TGF-ß1, resulted in binding which demonstrated saturation kinetics. Scatchard analyses revealed one class of receptors for HEPM (K 32.3 pM) and MEPM (K 26.3 pM). However, SDS-PAGE analyses of 125I-TGF-ß chemically crosslinked to specific receptor sites revealed that both cell types contained the types I (65,000 Mr) and III (230,000 Mr) TGF-ß receptors while MEPM also contained the type II (86,000 Mr) receptor. Binding studies further demonstrated the ability of platelet-derived growth factor to transmodulate TGF-ß binding. These results indicate that the HEPM cell line and primary cultures of MEPM cells, although obtained from palates at similar developmental stages, are dramatically different in their responsiveness to TGF-ß and have disparate TGF-ß receptor profiles.
Experimental cell research
Linask, Kersti K.; D'Angelo, Marina; Gehris, Amy; and Greene, Robert M., "Transforming growth factor-ß receptor profiles of human and murine embryonic palate mesenchymal cells" (1991). PCOM Scholarly Papers. 365.