Clinical grade of genetically corrected RPE cells for autologous cell therapy of hereditary retinal dystrophies

Abstract

AbstractPurpose: The generation of genetically corrected RPE cells from patient‐derived human induced pluripotent stem cells (hiPSCs) may provide a source for autologous therapeutically‐relevant therapy for this rare retinal dystrophy as well to create the human cellular disease models. Recently we generated a faithful RPE model from patient bearing mutation in MERTK gene and genetically corrected these cells using CRISPR/Cas9 system. For further application in humans is necessary to differentiate the hiPSC towards RPE in clinical grade conditions.Methods: The RPE cells from the genetically corrected patient‐derived hiPSC (1 and 2 alleles) as well as patient's RP‐hiPSC and control healthy hiPSC were characterized using immunocytological methods for the differentiation and polarization markers, electronic microscopy, RT‐PCR, TEER measurement, ELISA test, Western Blot and phagocytic assay.Results: All generated RPE cells exhibit typical features of RPE cells We demonstrated the reestablishment of the expression of full‐length MERTK protein as well as the reversion of lost phagocyte function of hiPSC‐RPE in vitro, which represents the first example of its kind in this field.Conclusions: The generated hiPSC‐derived RPE in clinical grade conditions display the typical characteristics of mature RPE cells re‐establishing the function of phagocytosis in genetically corrected patient‐derived RPE cells in vitro. Functional in vivo studies in animal models such as RCS rats or larger animals will confirm whether this strategy can completely restore the vision and be employed as a potential treatment for patients.