Photoreceptor Outer Segment-like Structures in Long-Term 3D Retinas from Human Pluripotent Stem Cells

Abstract

The retinal degenerative diseases, which together constitute a leading cause of hereditary blindness worldwide, are largely untreatable. Development of reliable methods to culture complex retinal tissues from human pluripotent stem cells (hPSCs) could offer a means to study human retinal development, provide a platform to investigate the mechanisms of retinal degeneration and screen for neuroprotective compounds, and provide the basis for cell-based therapeutic strategies. In this study, we describe an in vitro method by which hPSCs can be differentiated into 3D retinas with at least some important features reminiscent of a mature retina, including exuberant outgrowth of outer segment-like structures and synaptic ribbons, photoreceptor neurotransmitter expression, and membrane conductances and synaptic vesicle release properties consistent with possible photoreceptor synaptic function. The advanced outer segment-like structures reported here support the notion that 3D retina cups could serve as a model for studying mature photoreceptor development and allow for more robust modeling of retinal degenerative disease in vitro.

Thyroid hormone signaling specifies cone subtypes in human retinal organoids

“…Human retinal organoids generate photoreceptors that respond to light (10)(11)(12)(13)(14). We find that human organoids recapitulate the specification of cone subtypes observed in the human retina, including the temporal generation of S cones followed by L and M cones.…”

Single-cell analysis of human retina identifies evolutionarily conserved and species-specific mechanisms controlling development

“…We hypothesize that this difference results from the abrupt changes in culturing conditions with the addition or subtraction of growth factors, signaling pathway inhibitors, or oxygen during the human retinal organoid culturing process. One of these treatments, in particular, is the addition of the gamma-secretase and Notch-pathway inhibitor DAPT from days 29-45 of organoid culture to assist with photoreceptor specification (Jadhav et al, 2006; Wahlin et al, 2017; Yaron, 2006). Interestingly, 92.7% (1591 of 1716) of organoid-derived cones in our dataset were derived from organoids within this treatment window (i.e.…”

Culture Systems of Dissociated Mouse and Human Pluripotent Stem Cell–Derived Retinal Ganglion Cells Purified by Two-Step Immunopanning

“…These results are consistent with a previous report despite the different method used. 26 RGCs in 3D retinal organoids decreased gradually after DD 60; however, the purified RGCs during DD 90 to 110 were more vigorous when considering the neurite lengths and cell numbers. It is well known that RGCs decrease in numbers during maturation, 27 and our results suggest that human RGCs in 3D retinal organoids mature along with differentiation.…”