Induction of Functional 3D Ciliary Epithelium-Like Structure From Mouse Induced Pluripotent Stem Cells

To generate ciliary epithelium (CE) from mouse induced pluripotent stem (iPS) cells. Recently, a protocol for self-organizing optic cup morphogenesis in three-dimensional culture was reported, and it was suggested that ocular tissue derived from neural ectoderm could be differentiated. We demonstrated that a CE-like double-layered structure could be induced in simple culture by using a modified Eiraku differentiation protocol. Differentiation of a CE-like double-layered structure could be promoted by glycogen synthase kinase 3β (GSK-3β) inhibitor. Connexin43 and aquaporin1 were expressed in both thin layers, and induced CE-like cells expressed ciliary marker genes, such as cyclinD2, zic1, tgfb2, aldh1a3, wfdc1, otx1, BMP4, and BMP7. Increases in cytoplasmic and nuclear β-catenin in aggregates of the CE-like double-layered structure were confirmed by Western blot analysis. In addition, tankyrase inhibitor prevented the induction of the CE-like double-layered structure by GSK-3β inhibitor. Dye movement from pigmented cells to nonpigmented cells in the mouse iPS cell-derived CE-like structure was observed in a fluid movement experiment, consistent with the physiological function of CE in vivo. We could differentiate CE from mouse iPS cells in the present study. In the future, we hope that this CE-like complex will become useful as a graft for transplantation therapy in pathologic ocular hypotension due to CE dysfunction, and as a screening tool for the development of drugs for diseases associated with CE function.