Photoreceptor development in retinal organoids from human MGC-derived iPSCs. (a-e) Immunofluorescence staining of cryosections from retinal organoids at D175 using specific photoreceptor markers to identify both rods (Rhodopsin), cones (CAR, R/G Opsin, blue Opsin), and cilia marker (ARL13B). Nuclei were counterstained with DAPI (blue). (f, g) 3D views of solvent-cleared D175 retinal organoids immunostained for Cone arrestin (CAR) and CRX. (g) High-magnification image of isolated cones from (f) (white frame) with Imaris software (scale bars: 20 μm).