The Effect Of PEDF On The Cell Cycle Of Human Retinal Pigment Epithelium Cells In Vitro

Object To investigate the effect of Pigment epithelium-derived factor (PEDF)on the cell cycle of human retinal pigment epithelialium cells(hRPE) in vitro and to explore the possible mechanism about this action,in order to offer experimental evidence for clinical application.Methods The hRPE cells were harvested by enzyme dispase and identified by immnunocytochemistry(IC) with cytokeratin-18. The MTT assay for cell viability was used respectively to quantitate the effect of PEDF on cultured hRPE Cells with different concentrations and for different periods of time.The cell cycle and the expression of cyclin D1 of hRPE cells were detected by flow cytometry(FCM) and IC was applied to observe the expression of P16.Result The purity of hRPE cell population was up to 100% based on the proportion of CK-18 immunopositive cells in cultures.The absorbance of the PEDF groups were all higher than those of the control group (P <0.01).PEDF group increased the percentage of S period significantly(P <0.01), while decreased the proportion of G1/Go phrase (P <0.05). Normal hRPE cells expressed low levels of Cyclin D1 and PEDF strongly up-regulated it(P <0.01).Though the expression of P16 of the hRPE cells cultured with PEDF was higher than normal ones,there was no significant difference between them(P >0.05).Conclussion The datas demonstrate a dose-dependent and time-dependent proliferating effect of PEDF on cultured hRPE cells. PEDF can up-regulate the espression of Cyclin D1 much more significantly than that of P16 of hRPE cells,thus stimulate hRPE cells from G1 phase to S period overall.