Appilcation of polycaprolactone/collagen nanofibrous membranes in constituting tissue engineering retinal pigment epithelium

Objective To explore the potential of polycaprolactone (PCL)/gelatin nanofibrous composite membrane in constituting tissue engineering retinal pigment epithelium (RPE). Methods The embryonic stem cells (ESCs) were differentiated into RPE (ESC-RPE) cells by spontaneous differentiation methods.Flow cytometry was used to detect the expression of specific RPE markers in ESC-RPE cells.The nanofiber membrane of PCL and PCL/gelatin nanofibrous composite membrane were prepared by electrospinning.The topography and contact angle of the two membranes were detected.The viability of ESC-RPE cells treated by the extracts of the two kinds of membranes was detected by cell counting kit-8 (CCK-8)method.After the ESC-RPE cells were cultured on the PCL/gelatin nanofibrous composite membrane, immunostaining was used to detect the expression of specific RPE markers of tissue engineering RPE. Results ESC-RPE cells were negative for pluripotent marker OCT4, but positive for microphthalmia-associated transcription factor (MITF), RPE65 and Bestrophin.Both the nanofiber membrane of PCL and PCL/gelatin nanofibrous composite membrane were porous and the contact angle were (97.2±3.1)° and (13.6±2.4)°, respectively.The extracts of the two kinds of membranes showed no significant effect on the growth of ESC-RPE cells.The tissue engineering RPE based on PCL/gelatin nanofibrous composite membrane positively expressed MITF and ZO-1. Conclusions PCL/gelatin nanofibrous composite membrane shows good hydrophilicity and biocompatibility.Besides, the membrane is favor for the growth of ESC-RPE cells and holds the potential to constitute tissue engineering RPE. Key words: Retinal pigment epithelium; Retinal degeneration diseases; Polycaprolactone; Collagen; Tissue engineering