Scientists have found a long-sought-after population of stem cells in the retina of human fetuses that could be used to develop therapies for retinal degeneration, leading to blindness. The discovery was made by precisely measuring individual cell types’ gene expression in eye samples from fetuses donated after terminated pregnancies.
A team of researchers led by Jianzhong Su found a distinct population of cells that differed from previously described retinal progenitor cells (RPCs). These cells, called human neural retinal stem-like cells (hNRSCs), can rapidly proliferate and develop into various other retinal cells. When transplanted into the eyes of mice with a condition resembling retinitis pigmentosa, these human cells generated RPCs and other cell types in the retina over the course of roughly 4 months.
The researchers also explored whether hNRSCs could be produced without using fetal tissue by studying human retinal organoids. They found that some cells within those organoids had gene expression similar to that of hNRSCs, which generated RPCs and other cell types in the retina when transplanted into mice with a condition resembling retinitis pigmentosa.
The discovery has significant implications for regenerative medicine and cell-based therapies for retinal degenerative disease. However, some researchers remain skeptical until they see more evidence that hNRSCs are distinct from RPCs and can integrate and functionally restore vision in murine models of retinal degeneration.
Researchers believe hNRSCs could offer therapeutic advantages over current experimental cell-based therapies, as they are better at self-renewing and easier to produce than reprogrammed mature cells. The team is now working to improve their methods of growing and transplanting hNRSCs and testing their effects in larger animals such as monkeys.
Source: https://www.science.org/content/article/elusive-stem-cells-discovered-human-retina-may-lead-treatment-blindness