Lab-grown retina traces vision loss in Batten disease

A child with CLN3-Batten disease may first notice the world becoming harder to read, learn from and navigate. At the University of Rochester Medicine Flaum Eye Institute, researchers have now used a 3D human stem cell-derived retina to trace how that loss of vision may begin—in the support cells beneath light-sensing photoreceptors.

The model recreates the relationship between photoreceptors and the retinal pigment epithelium, or RPE, a layer of support cells beneath them. That relationship has been difficult to study because the earliest damage occurs deep inside the retina. The team found that malfunction in the RPE alone could set off photoreceptor degeneration, offering an explanation for why vision loss often arrives before the disease’s neurological symptoms.

The biological clue was acid ceramidase, or AC, an enzyme that helps regulate fats inside cells. CLN3-Batten disease cells had reduced AC levels and developed harmful lipid imbalances associated with retinal damage. The researchers then tested recombinant human acid ceramidase, known as rhAC, in the lab-grown retinas and in a large-animal model; the treatment improved cellular health and reduced signs of degeneration.

And concretely? The work gives researchers a human-relevant system for testing treatments before patients are involved, while pointing toward an approach that supports both the retina’s light-sensing cells and the cells that maintain them. It may also help refine gene therapies and drugs aimed at lipid metabolism already being developed for CLN3 disease.

The boundary is clear: rhAC remains a treatment candidate, not a therapy tested in patients. The Rochester team says future studies must examine long-term safety and effectiveness, as well as whether the strategy can address parts of CLN3-Batten disease beyond vision loss.