Expression of Integrins and Adhesive Properties of Human Endothelial Cell Line EA.hy 926

Immortalized endothelial cell lines are very often used as a model of endothelium for studies of various processes connected with its functions. Among the hybrid cells, the EA.hy 926 cell line, derived by the fusion of HUVECs with the continuous human lung carcinoma cell line A549, is presently the best characterized macro-vascular endothelial cell line. Although EA.hy 926 cells retain several endothelial characteristics, our data show some differences between this cell line and primary human umbilical vein endothelial cells (HUVEC). Analysis of their proteomic pattern reveals that there are many proteins expressed only in the immortalized cell line, but several proteins of EA.hy 926 are missed when compared to HUVECs. We observed a distinct profile of integrin expression on the surface of both types of endothelial cells, that may be responsible for diminished EA.hy 926 adhesion and migration to selected adhesive proteins. Studies on proliferation and migration in the presence of VEGF showed lower growth factor responsiveness of EA.hy 926 in comparison with HUVECs, but hybrid endothelial cells can also be converted into a pro-angiogenic phenotype. These studies showed significant similarity of endothelial cell lines with primary HUVECs, but also pointed out marked phenotype differences.