Retinal Pigment Epithelial Cells from Thermally Responsive Polymer-Grafted Surface Reduce Apoptosis

Brain-derived neurotrophic factor (BDNF) has reported to show photoreceptor protection for retinal degeneration either genetically programmed,1 or light induced experimental retinal degeneration.2 Genetically modified BDNF gene expressing cell transplantation in the subretinal space also rescued light induced photoreceptor degeneration.3 When we consider the genetically modified BDNF gene expressing cell transplantation, the fate or the behavior of the cell at the subretinal regions has still unclear, especially at the diseased subretinal lesions. The cells placed at deeper layer of bruch membrane tend to be affected by apoptosis.4 The fate of the transplanted cell may be one of the important factors for success of the transplantation. Cells cultured on poly-(N-isopropylacrylamide (PIPAAm)-grafted plates were easily detached from the culture plates as cell sheet by reducing the temperature from 37° C to 20° C without using enzymes.5 We further cultured the cell and examined the degree of apoptosis by comparing with those of cells collected by trypsin treatment.