Immunofluorescence Assays of RPE Cell Markers

The immunofluorescence assays were performed as previously described in Feng et al. (64 (link)). HsRPE cells were fixed with 4% paraformaldehyde for 15 min, followed by blocking with 5% BSA at room temperature for 1 h. The cell samples were incubated with RPE65 (Abcam, ab235950), F-actin (Abcam, ab130935), CCT5 (Proteintech, 11603-1-AP), and MERTK (Cell Signaling Technology, 4319S) antibodies. Cell samples were then incubated with secondary antibodies for 1 h at room temperature. Subsequently, the nuclei of the cells were stained using DAPI for 7 min. All the images were taken using a confocal microscope (Carle ZEISS LSM 980, Oberkohen, Germany).