PURPOSE: To determine whether the delivery of the SV40 large T-antigen is a feasible method for transiently inducing proliferation of corneal endothelial cells, we delivered liposome-protein complex into bovine corneal endothelial cells(BCEC). METHOD: SV40 large T-antigen protein was introduced into BCEC and positive cells were identified by immunohistochemistry. Quiescent BCECs were double-labeled using BrdU as a measure of de novo DNA synthesis and the Ki-67 was detected by standard immunohistochemical methods. RESULT: The treatment of quiescent BCECs with large T antigen caused an increase in BrdU incorporation and Ki-67 expression. It was tested by time-course study. CONCLUSION: This finding suggests that liposome-mediated delivery of transforming proteins could be a method to transiently induce corneal endothelial cell proliferation.
Antigens, Viral, Tumor* ; Bromodeoxyuridine ; Cell Proliferation ; DNA ; Endothelial Cells* ; Immunohistochemistry

The coeneal endothelium is essential for the maintenance of normal corneal hydration, thickness, and transparency. However, corneal endothelial cells are incapable of significant proliferation in vivo. As we age, the density of corneal endothelial (CEN) cells gradually decreases. The goal of our study is to explore the possibility of enhancing the proliferation of corneal endothelial cells by introduction of SV 40 large T antigen, a transforming protein. To this end, introduction of protein into CEN cells was assessed by liposome assisted beta-galactosidase transfection in vivo, ex vivo, and in vivo. In all cases, cells treated with liposome-protein complex have shown dramatic blue stain in beta-galactosidase activity staining. This result convinced us that we could artificially introduce a foreign protein into a cell. To ascertain where SV 40 large T antigen is localized in the cell, purified SV 40 large T antigen was transfected into the cells using liposome and its presence was determined immunohistochemically. We show that the liposome delivered SV 40 large is localized in the nucleus and mitotic figures which may suggest its functional activity.
Antigens, Viral, Tumor* ; beta-Galactosidase ; Endothelial Cells* ; Endothelium ; Liposomes ; Transfection*