Retinal ganglion cells harboring the OPTN(E50K) glaucoma mutation exhibit neurodegenerative phenotypes when derived from hPSC-derived three dimensional retinal organoids

Abstract

Retinal ganglion cells (RGCs) serve as the primary connection between the eye and the brain, with this connection disrupted in glaucoma. Numerous cellular mechanisms have been associated with glaucomatous neurodegeneration, and useful models of glaucoma allow for the precise analysis of degenerative phenotypes. Human pluripotent stem cells (hPSCs) serve as powerful tools for studying human neurodegenerative diseases, particularly cellular mechanisms underlying degeneration. Thus, efforts were initially focused upon the use of hPSCs with an E50K mutation in the Optineurin (OPTN) gene. CRISPR/Cas9 gene editing was used to introduce the OPTN(E50K) mutation into existing lines of hPSCs, as well as the generation of isogenic control lines from OPTN(E50K) patient-derived hPSC lines. OPTN(E50K) RGCs exhibited numerous neurodegenerative deficits, including neurite retraction, autophagy dysfunction, apoptosis, and increased excitability. The results of this study provide an extensive analysis of the OPTN(E50K) mutation in hPSC-derived RGCs, with the opportunity to develop novel treatments for glaucoma.