SOX2-positive retinal stem cells are identified in adult human pars plicata by single-cell transcriptomic analyses. SOX2-positive retinal stem cells are identified in adult human pars plicata by single-cell transcriptomic analyses

Stem cell therapy is a promising strategy to rescue visual impairment caused by retinal degeneration. Previous studies have proposed controversial theories about whether in situ retinal stem cells (RSCs) are present in adult human eye tissue. Single-cell RNA sequencing (scRNA-seq) has emerged as one of the most powerful tools to reveal the heterogeneity of tissue cells. By using scRNA-seq, we explored the cell heterogeneity of different subregions of adult human eyes, including pars plicata, pars plana, retinal pigment epithelium (RPE), iris and neural retina (NR). We identified one subpopulation expressing SOX2 as RSCs, which were present in the pars plicata of the adult human eye. Further analysis showed the identified subpopulation of RSCs expressed specific markers AQP1 and TSPAN12. We therefore isolated this subpopulation using these two markers by flow sorting and found that the isolated RSCs could proliferate and differentiate into some retinal cell types, including photoreceptors, neurons, RPE cells, microglia, astrocytes, horizontal cells, bipolar cells and ganglion cells; whereas, AQP1- TSPAN12- cells did not have this differentiation potential. In conclusion, our results showed that SOX2-positive RSCs are present in the pars plicata and may be valuable for treating human retinal diseases due to their proliferation and differentiation potential. Overall design: pars plicata, pars plana, RPE, iris and NR cells were isolated from the eyes of 6 donors and profiled with single-cell RNA sequencing(10× Genomics).cDNA libraries were generated using the Chromium Single cell 3’ V3 kit.