Integration and Differentiation of Transplanted Human iPSC-Derived Retinal Ganglion Cell Precursors in Murine Retinas

Optic neuropathy such as glaucoma, stemming from retinal ganglion cell (RGC) degeneration, is a leading cause of visual impairment. Given the substantial loss of RGCs preceding clinical detection of visual impairment, cell replacement therapy emerges as a compelling treatment strategy. Human-induced pluripotent stem cells (hiPSCs) serve as invaluable tools for exploring the developmental processes and pathological mechanisms associated with human RGCs. Utilizing a 3D stepwise differentiation protocol for retinal organoids, we successfully differentiated RGC precursors from hiPSCs harboring a BRN3B-GFP RGC reporter, verified by GFP expression. Intravitreal transplantation of enriched RGC precursors into healthy or N-methyl-D-aspartate (NMDA)-injured mice demonstrated their survival, migration, and integration into the proper retinal layer, the ganglion cell layer, after 3 weeks. Notably, these transplanted cells differentiated into marker-positive RGCs and extended neurites. Moreover, enhanced cell survival was observed with immunosuppressive and anti-inflammatory treatments of the host prior to transplantation. These data underscore the potential of transplanted RGC precursors as a promising therapeutic avenue for treating degenerative retinal diseases resulting from RGC dysfunction.