Genomic characterization of sub-populations in human pluripotent stem cell-derived retinal progenitor cells that drive retinal layer structure

Single-cell RNA sequencing revealed that well-layered spheroids exhibited a transient activation of canonical WNT2B–FZD7 signaling followed by a temporary expression of non-canonical WNT5A, processes associated with the formation of organized retinal layers.

Despite structural differences in vitro, both non-layered and well-layered retinal spheroids of differentiation day 60 successfully developed into each cone and rod subtypes of photoreceptors and established synaptic connections with host bipolar cells after transplantation in retinal degeneration model rats, resulting in light-evoked functional recovery. Additionally, part of the presumable RPCs differentiated into non-retinal lineages, including ciliary marginal zone-like, retinal pigment epithelium-, and spinal cord-like tissues in vitro, reflecting the developmental plasticity of RAX-positive cells.