RPE Derived from Pluripotent Stem Cell Lines Display Mature RPE Characteristics
(A) RPE derived from wild-type and MERTK mutant hPSC grown in Transwells.
(B) HPSC-derived RPE are pigmented and express mature RPE markers, including MITF, EZRIN, bestrophin 1 (BEST1), and ZO1. MERTK is expressed in hESC-RPE, but not in EX2 and MERTK-RPE. It is weakly expressed in EX14-RPE. Scale bar, 10 μm.
(C) Cross-sections of immunofluorescence images of RPE markers in hESC-RPE and MERTK-RPE. Note the polarized expression of ZO1, EZRIN, and MERTK on the apical surface of the RPE. Scale bar, 10 μm.
(D) Heatmap of the mean of log2 values of reads per kilobase of transcript per million mapped reads of selected pluripotency genes and mature RPE markers. N = 3 biological repeats. Presented data are derived from RNA-seq analysis performed on hESCs and hESC-RPE. Please refer to Excel Table S1 for raw data. The accession number for the RNAseq data reported here is GEO: GSE127352.
(E) Immunoblot (western blot) analysis of MERTK using total protein extracts from wild-type and MERTK mutant RPE.
(F) Analysis of three MERTK immunoblots using ImageJ showed a decrease in MERTK expression in EX14-RPE, and no MERTK expression in EX2-RPE and MERTK-RPE. Data are represented as means ± SD. N = 3 biological repeats.