Researchers from Duke-NUS Medical School, the Singapore Eye Research Institute, and the Karolinska Institute in Sweden have developed a method of producing photoreceptor progenitor cells using stem cells that may be used to restore vision in patients with eye diseases characterized by photoreceptor loss. The study, conducted on preclinical models, showed partial recovery of retinal function after transplanting these cells into the models. Photoreceptor degeneration is one of the leading causes of vision loss and blindness, and there is currently no effective treatment. Age-related macular degeneration and retinitis pigmentosa are eye diseases characterized by photoreceptor loss.

The researchers developed a procedure that directed stem cells to differentiate into photoreceptor progenitor cells by growing human embryonic stem cells in the presence of purified laminin proteins, which are essential for the normal development of human retinas. The photoreceptor progenitor cells were transplanted into damaged retinas, showing significant vision recovery. The transplanted cells established connections with surrounding retinal cells and nerves in the inner retina and survived and functioned for many weeks after transplantation. The researchers plan to refine the method and achieve more consistent results for future studies.

The researchers hope the method may help understand the molecular and cellular pathways that drive the progression of macular degeneration, leading to the development of other therapeutic approaches. They are also planning to explore their method’s efficacy in photoreceptor degeneration models that more closely match the human condition. If the researchers get promising results in future studies, they hope to move to clinical trials in patients, which would be a significant step toward being able to reverse the damage of the retina and restore vision. Meanwhile, the protocol underlying the procedure developed by the researchers has been licensed to Swedish biotech start-up Alder Therapeutics. 

This new research was published in Molecular Therapy.

References

• Duke-NUS Medical School. (2023, April 14). Scientists from Singapore and Sweden achieve promising results towards restoring vision in blindness caused by cellular degeneration in the eye. Duke-NUS Medical School; Duke-NUS Medical School. https://www.duke-nus.edu.sg/allnews/stem-cell-approach-for-correcting-photoreceptor-cell-degeneration

• Tay, H. G., Andre, H., Chrysostomou, V., Adusumalli, S., Guo, J., Ren, X., Tan, W. S., Tor, J. E., Moreno-Moral, A., Plastino, F., Bartuma, H., Cai, Z., Tun, S. B. B., Barathi, V. A., Siew Wei, G. T., Grenci, G., Chong, L. Y., Holmgren, A., Kvanta, A., … Tryggvason, K. (2023). Photoreceptor laminin drives differentiation of human pluripotent stem cells to photoreceptor progenitors that partially restore retina function. Molecular Therapy, 31(3), 825–846. https://doi.org/10.1016/j.ymthe.2022.12.012