Losing your vision can be frightening but earlier this year, Swiss scientists made a breakthrough that could change how we treat eye diseases. In this recent study, researchers bring stem cells in the human eye into sharp focus. These newly discovered multipotent stem cells in the retina could one day help to repair damaged vision.
Stem Cell Stories
In April 2025, neuroscientists from the University of Lausanne and the Swiss Federal Institute of Technology published a research paper in Science Translational Medicine announcing a new type of cell in the human eye, that they have named ‘human neuroretinal stem-like cells’ (hNRSCs). This discovery shows that we might have a natural way to repair vision loss hiding in our own eyes.
These multipurpose regenerating cells could, in future, help us to repair the retina, grow personalized eye cells for therapy, and create new options for treating forms of blindness that currently have no cure. According to the World Health Organization, at least 2.2Â billion people worldwide have a vision impairment or blindness, many losing their sight due to retinal damage. Using specialized stem cells from the eye itself could transform how we treat vision loss.Â
Seeing the Bigger Picture
Researchers have been exploring regenerative medicine to cure vision loss for a long time. Some animals, like fish, can regrow parts of their eyes, but until now, it wasn’t clear whether humans also have special cells with this capacity. When fish damage their retina, they’re able to regenerate it using their own retinal stem cells, restoring lost vision. Eye scientists realized that if this natural repair process could be replicated in humans, it might be possible to cure vision loss caused by diseases like macular degeneration, retinitis pigmentosa or diabetic retinopathy. This idea has sparked a decades-long quest to find an equivalent population of regenerative cells in the human eye.
The retina is a thin layer of tissue at the back of the eye that captures light and sends signals to the brain, helping us to see. Damage to the retina causes people to lose their sight. Scientists have been looking for stem cells in the eye that can fix this damage, but they hadn’t found the right ones until now.
Stem Cells in the Retina
Stem cells are a specialized cell type that can turn into different kinds of cells in the body. They help repair damaged tissue and replace cells that are lost or damaged. In the eye, doctors have already been using artificial stem cells grown in the lab to try to treat a disease called macular degeneration.
Macular degeneration happens when blood vessels that feed the retina get leaky causing vision loss as people get older. Using transplanted induced stem cells to repair these blood vessels has been a huge step forward, but this therapy targets blood vessels rather than the retina itself. This new cell type is different to the ones used to treat macular degeneration. Unlike induced stem cells, human neuroretinal stem-like cells (hNRSCs), are already in place, and have the ability to turn into specialized cells only found in the eye.Â
These new cells could be even better at fixing damage because they come from the retina itself. In the future, researchers hope that hNRSCs could help treat not only macular degeneration, but also other serious eye diseases like retinal detachment and retinitis pigmentosa. Finding these cells opens up a new way to heal the eye using its own natural tools.
The Search is On
Researchers looked at human fetal eye tissue using high-tech tools that help them study individual cells.Â
The team suspected, based on research in other animals that humans might have stem cell-like cells at the edges of the retina, in an area called the ciliary marginal zone. This part of the eye hasn’t been well studied in humans. Thanks to advances in technology, the researchers were able to take a closer look.Â
Using a method called single-cell RNA sequencing, they analysed thousands of individual retinal cells to see which genes were active in each one. By comparing the patterns of gene activity, they spotted a small group of cells with a stem cell signature suggesting these cells could multiply and turn into the types of cells needed to build and repair the retina.
Finding these cells wasn’t easy. They represent less than 1% of the cells in the retina, making them incredibly rare and hard to detect. It took a lot of careful work and new technology to spot them among the many different cell types in the eye. But this discovery could change the way scientists think about healing vision loss.
Eyes in a dish?
The next step was to answer the questions, do these cells we found behave like stem cells? Do they turn into retinal cells? Can we use them to repair the retina?
The researchers collected as many of the hNRSCs from donated human retinas as they could and cultured them in the lab. Rather than needing extensive reprogramming or genetic modification, these cells were able to grow and multiply under specialized but relatively simple conditions. Even more remarkably, they naturally developed into a range of retinal cell types needed to build the complex structures of the eye. This discovery means scientists could one day grow mini retinas in a dish, opening up new possibilities for studying human eye diseases, screening drugs, and testing gene therapies, tasks that were difficult before because of limited access to human eye tissue and less accurate cell models.Â
The new cells, called human neuroretinal stem-like cells (hNRSCs), were able to make copies of themselves, turn into important eye cells like photoreceptors (which help us see light), and help repair the retina. In mice with eye damage, the cells even improved vision. In other words, these new cells could regrow parts of the eye and help restore sight.
Turning a critical eye
This research is still new, but it’s very promising. The team believes that these cells could help treat vision loss caused by retinal damage including conditions like macular degeneration, retinitis pigmentosa, or diabetic retinopathy.
For now, these stem cells will be most valuable as a research tool. Scientists can use them to study how retinal cells respond to different treatments and to better understand how hNRSCs behave. But there’s still a lot we don’t know. These cells are so new that researchers are only beginning to uncover their properties. They’re hidden at the very edge of the retina, which raises the challenge of figuring out how to ‘wake them up’ or activate them to repair damage. We also don’t yet know why they don’t naturally fix retinal injuries on their own. And because they’re embedded deep inside the eye, unlike easily accessible stem cells from places like bone marrow, scientists will need to find safe ways to isolate or target them for therapy.
Unlike current treatments that use lab-grown cells, human neuroretinal stem-like cells (hNRSCs) come from the eye itself and can naturally grow into many types of eye cells. Liu, Su, and their colleagues say more testing is needed before trying it in humans, but their discovery could lead to better and more natural ways to restore sight.
References
Liu, H., Ma, Y., Gao, N., Zhou, Y., Li, G., Zhu, Q., Liu, X., Li, S., Deng, C., Chen, C., Yang, Y., Ren, Q., Hu, H., Cai, Y., Chen, M., Xue, Y., Zhang, K., Qu, J., & Su, J. (2025). Identification and characterization of human retinal stem cells capable of retinal regeneration. Science Translational Medicine, 17 (791). https://doi.org/10.1126/scitranslmed.adp6864
Losing your vision can be frightening but earlier this year, Swiss scientists made a breakthrough that could change how we treat eye diseases. In this recent study, researchers bring stem cells in the human eye into sharp focus. These newly discovered multipotent stem cells in the retina could one day help to repair damaged vision. In April 2025, neuroscientists from the University of Lausanne and the Swiss Federal Institute of Technology published a research paper in Science Translational Medicine announcing a new type of cell in the human eye, that they have named ‘human neuroretinal stem-like cells’ (hNRSCs). This discovery shows that we might have a natural way to repair vision loss hiding in our own eyes. These multipurpose regenerating cells could, in future, help us to repair the retina, grow personalized eye cells for therapy, and create new options for treating forms of blindness that currently have no cure. According to the World Health Organization, at least 2.2 billion people worldwide have a vision impairment or blindness, many losing their sight due to retinal damage. Using specialized stem cells from the eye itself could transform how we treat vision loss. Researchers have been exploring regenerative medicine to cure vision loss for a long time. Some animals, like fish, can regrow parts of their eyes, but until now, it wasn’t clear whether humans also have special cells with this capacity. When fish damage their retina, they’re able to regenerate it using their own retinal stem cells, restoring lost vision. Eye scientists realized that if this natural repair process could be replicated in humans, it might be possible to cure vision loss caused by diseases like macular degeneration, retinitis pigmentosa or diabetic retinopathy. This idea has sparked a decades-long quest to find an equivalent population of regenerative cells in the human eye. The retina is a thin layer of tissue at the back of the eye that captures light and sends signals to the brain, helping us to see. Damage to the retina causes people to lose their sight. Scientists have been looking for stem cells in the eye that can fix this damage, but they hadn’t found the right ones until now. Stem cells are a specialized cell type that can turn into different kinds of cells in the body. They help repair damaged tissue and replace cells that are lost or damaged. In the eye, doctors have already been using artificial stem cells grown in the lab to try to treat a disease called macular degeneration. Macular degeneration happens when blood vessels that feed the retina get leaky causing vision loss as people get older. Using transplanted induced stem cells to repair these blood vessels has been a huge step forward, but this therapy targets blood vessels rather than the retina itself. This new cell type is different to the ones used to treat macular degeneration. Unlike induced stem cells, human neuroretinal stem-like cells (hNRSCs), are already in place, and have the ability to turn into specialized cells only found in the eye. These new cells could be even better at fixing damage because they come from the retina itself. In the future, researchers hope that hNRSCs could help treat not only macular degeneration, but also other serious eye diseases like retinal detachment and retinitis pigmentosa. Finding these cells opens up a new way to heal the eye using its own natural tools. Researchers looked at human fetal eye tissue using high-tech tools that help them study individual cells. The team suspected, based on research in other animals that humans might have stem cell-like cells at the edges of the retina, in an area called the ciliary marginal zone. This part of the eye hasn’t been well studied in humans. Thanks to advances in technology, the researchers were able to take a closer look. Using a method called single-cell RNA sequencing, they analysed thousands of individual retinal cells to see which genes were active in each one. By comparing the patterns of gene activity, they spotted a small group of cells with a stem cell signature suggesting these cells could multiply and turn into the types of cells needed to build and repair the retina. Finding these cells wasn’t easy. They represent less than 1% of the cells in the retina, making them incredibly rare and hard to detect. It took a lot of careful work and new technology to spot them among the many different cell types in the eye. But this discovery could change the way scientists think about healing vision loss. The next step was to answer the questions, do these cells we found behave like stem cells? Do they turn into retinal cells? Can we use them to repair the retina? The researchers collected as many of the hNRSCs from donated human retinas as they could and cultured them in the lab. Rather than needing extensive reprogramming or genetic modification, these cells were able to grow and multiply under specialized but relatively simple conditions. Even more remarkably, they naturally developed into a range of retinal cell types needed to build the complex structures of the eye. This discovery means scientists could one day grow mini retinas in a dish, opening up new possibilities for studying human eye diseases, screening drugs, and testing gene therapies, tasks that were difficult before because of limited access to human eye tissue and less accurate cell models. The new cells, called human neuroretinal stem-like cells (hNRSCs), were able to make copies of themselves, turn into important eye cells like photoreceptors (which help us see light), and help repair the retina. In mice with eye damage, the cells even improved vision. In other words, these new cells could regrow parts of the eye and help restore sight. This research is still new, but it’s very promising. The team believes that these cells could help treat vision loss caused by retinal damage including conditions like macular degeneration, retinitis pigmentosa, or diabetic retinopathy. For now, these stem cells will be most valuable as a research tool. Scientists can use them to study how retinal cells respond to different treatments and to better understand how hNRSCs behave. But there’s still a lot we don’t know. These cells are so new that researchers are only beginning to uncover their properties. They’re hidden at the very edge of the retina, which raises the challenge of figuring out how to ‘wake them up’ or activate them to repair damage. We also don’t yet know why they don’t naturally fix retinal injuries on their own. And because they’re embedded deep inside the eye, unlike easily accessible stem cells from places like bone marrow, scientists will need to find safe ways to isolate or target them for therapy. Unlike current treatments that use lab-grown cells, human neuroretinal stem-like cells (hNRSCs) come from the eye itself and can naturally grow into many types of eye cells. Liu, Su, and their colleagues say more testing is needed before trying it in humans, but their discovery could lead to better and more natural ways to restore sight. Liu, H., Ma, Y., Gao, N., Zhou, Y., Li, G., Zhu, Q., Liu, X., Li, S., Deng, C., Chen, C., Yang, Y., Ren, Q., Hu, H., Cai, Y., Chen, M., Xue, Y., Zhang, K., Qu, J., & Su, J. (2025). Identification and characterization of human retinal stem cells capable of retinal regeneration. Science Translational Medicine, 17 (791). https://doi.org/10.1126/scitranslmed.adp6864Stem Cell Stories
Seeing the Bigger Picture
Stem Cells in the Retina
The Search is On
Eyes in a dish?
Turning a critical eye
References
