Published online Oct 26, 2020. doi: 10.4252/wjsc.v12.i10.1171
Peer-review started: June 11, 2020
First decision: June 20, 2020
Revised: July 3, 2020
Accepted: August 16, 2020
Article in press: August 16, 2020
Published online: October 26, 2020
Processing time: 137 Days and 2.3 Hours
Degenerative eye diseases, such as glaucoma, are characterized by a progressive loss of retinal ganglion cells (RGCs), neurons within the eye required for image and non-image transformation. RGCs have been shown to interact with, and be dependent upon, Müller glia. Both cell types are central in the pathology of glaucoma.
The development of in vitro differentiation protocols for generating retinal cells and tissues is crucial to identify disease-relevant cellular changes and to test potential intervention strategies in a human context.
In this study we investigated the potential of retinal organoids to produce RGC and Müller glia progenitors and the efficiency with which these cell types can be isolated and expanded as enriched monolayer cultures.
Retinal organoids were differentiated from human induced pluripotent stem cells (hiPSCs), then magnetic-activated cell sorting applied to isolate RGC and Müller glia progenitors. Gene and protein expression were assessed in both retinal organoids and monolayers of RGC and Müller glia progenitors via qPCR and immunocytochemistry respectively. Furthermore, retinal organoid ultrastructure was examined via transmission electron microscopy.
Retinal organoids were grown successfully for at least 56 d and the presence of RGC and Müller glia progenitors validated via optimized whole mount immuno-cytochemistry. Furthermore, pure populations of RGC and Müller glia progenitors could be isolated using magnetic-activated cell sorting and successfully propagated in enriched monolayers for up to 2 wk.
Retinal organoids generated from hiPSCs recapitulate eye development in terms of their cellular heterogeneity and tissue architecture. Key cell types, such as RGC and Müller glia progenitors, can be isolated from the retinal organoids and expanded for subsequent cell-specific phenotype characterizations in disease-relevant contexts.
In vitro generation of the relevant cell types affected by degenerative eye diseases is important in order to study specific cell type disease vulnerability and selective cellular interactions. The generation of retinal organoids with subsequent isolation of RGC and especially Müller glia progenitors is an important step for in vitro disease modeling.