A team at the National Institutes of Health has developed a pioneering microsurgical technique enabling the implantation of multiple subretinal tissue grafts—a breakthrough that may significantly enhance the evaluation and scalability of retinal cell therapies for dry age-related macular degeneration (AMD). Currently, surgical protocols limit ophthalmic surgeons to placing a single graft per eye, restricting both therapeutic reach and the ability to directly compare treatment modalities. NIH investigators have now addressed this limitation by designing a custom surgical clamp that maintains intraocular pressure and minimizes iatrogenic trauma during sequential subretinal deliveries.
In a preclinical AMD model, the team successfully implanted 2 adjacent grafts within the same lesion: 1 comprised of stem cell–derived retinal pigment epithelium (RPE) on a biodegradable scaffold, and the other a scaffold-only control. This approach enabled intraocular side-by-side comparisons—a critical advance for optimizing graft design and delivery.
Notably, AI-assisted imaging analysis revealed that RPE grafts promoted photoreceptor preservation and even supported choriocapillaris regeneration—outcomes not observed in the scaffold-only control group. These findings suggest improved graft integration with both retinal and vascular structures.
For ophthalmic surgeons and clinician-researchers, this dual-implant technique represents a significant step forward. It offers a new toolset for refining surgical approaches, expands the evaluative potential of preclinical models, and may ultimately accelerate the transition of retinal regenerative therapies from bench to bedside.
The findings build on earlier work published by NIH scientists in Science Translational Medicine, which demonstrated the efficacy of clinical-grade stem cell–derived RPE patches in rescuing retinal degeneration in rodent and pig models.
“In the future,” the authors wrote in their full article in JCI Insight, “we plan to extend this work and compare the relative efficacy of different RPE subpopulations (macular cells vs peripheral cells) and RPE-only transplants with dual RPE/photoreceptor transplants.
The work was supported by the National Eye Institute’s Intramural Research Program.
Source: NIH