Scientists have identified never-before-seen cells in the human eye that could potentially help reverse vision loss caused by common diseases, such as macular degeneration.
The researchers discovered the cells in the retina, a light-sensitive structure at the back of the eye that is vital for vision. The cells were found in donated samples of fetal tissue. The scientists also identified the same cells in lab-grown models of the human retina — and when they tried transplanting those models into mice with a common eye disorder, it restored the rodents’ vision.
“This research not only deepens our understanding of retinal biology but also holds immense potential for advancing therapeutic interventions in RD [retinal degeneration] diseases,” the researchers wrote in a paper describing the findings, which was published in the journal Science Translational Medicine. The retina detects light and converts it into signals that the brain can then interpret to determine what we’re seeing. Deterioration of the retina is a leading cause of blindness worldwide. It can be triggered by many things, including aging, diabetes and physical injury, and the degeneration can lead to common eye diseases, such as macular degeneration and retinitis pigmentosa.
Current treatments for these conditions focus mainly on reducing the rate at which retinal cells deteriorate, and protecting those that are still healthy. However, there are currently no effective therapies that promote repair of the retina, which would effectively reverse the deterioration.
A potential solution is to replace deteriorated cells with stem cells — cells that can mature to become any type of cell in the body under the right conditions. Yet, until now, scientists haven’t found suitable stem cells in the human retina to achieve this, the authors of the new study wrote. In the new research, the team analyzed the activity of cells in the fetal retinal samples in the lab. The scientists discovered two types of retinal stem cells with promising regenerative properties: human neural retinal stem-like cells (hNRSCs) and retinal pigment epithelium (RPE) stem-like cells.