The Expression of ST2 Gene in Vascular Endothelial Cells and in Mouse Model of Oxygen–Induced Retinopathy

Abstract

Abstract: : Purpose: The ST2 gene was originally cloned as a primary response gene induced by growth stimulation in BALB/c–3T3 cells. This gene produces two mRNAs by alternative splicing, one is ST2 that encodes a soluble secreted protein, and the other is ST2L that encodes a membrane bound protein whose extracellular domain is identical with the soluble protein. We examined the expression of the ST2 gene in vascular endothelial cells and retinae with neovascular formation. Methods: The expressions of ST2 and ST2L mRNAs were studied in primary cultures of human umbilical vein endothelial cells (HUVECs), human dermal microvascular endothelial cells from Adult (HMvEs–Ad), human aortic endothelial cells (HAECs), and human retinal vascular endothelial cells (RECs) by RT–PCR. HUVECs and RECs were grown on Matrigel to form capillary like structures, and the expressions of ST2 and ST2L mRNAs were studied at 12h, 24h and 48h after spreading. Moreover, the mRNAs expression of ST2 and ST2L were analyzed in a mouse model of oxygen–induced retinopathy by real–time PCR. The gene expression in the mouse model was compared to age–matched controls. Results: The expressions of ST2 and ST2L mRNAs were detected in all materials. They were also expressed in the capillary like structures using Matrigel at 12h, but not expressed at 24h and 48h. The ST2 gene was induced in the retinae of oxygen–loaded mice as compared to control mice. Conclusions: These results suggest that ST2 might be involved in vascular endothelial cell growth and neovascularization in oxygen–induced retinopathy.

Keywords: gene/expression • hypoxia • vascular cells