Transforming growth factor beta 1 (TGF–ß1) regulates vascular development by modulating Tie2 promoter activity in vivo.

Abstract

Abstract: : Purpose: Transforming growth factor beta 1 (TGF–ß1) is necessary for the differentiation of stable blood vessels. Tie2 expression endothelial cells is also necessary for development of stable blood vessels. We have found that transgenic expression of TGF–ß1 disrupts establishments of stable blood vessels. The purpose of this study is to determine the mechanism by which TGF–ß1 is interfering in angiogenesis. Methods: We have adopted real–time PCR and immunohistochemistry to identify the regulation of Tie2 expression in retinal tissue of TGF–ß1 transgenic mice. Results: TGF–ß1 transgenic mice exhibit lower levels of Tie2 expression when compared to non–transgenic mice. Our real–time PCR and immunohistochemistry analyses have confirmed that Tie2 expression in retinas from transgenic TGF–ß1 mice is reduced. Conclusions: There is a significant difference in Tie2 expression in TGF–ß1 transgenic mice. Our results suggest that TGF–ß1 is involved in the regulation of Tie2 signaling but the actual mechanism of transcriptional regulation remains unknown.

Keywords: vascular cells • transgenics/knock–outs • growth factors/growth factor receptors