Injecting healthy cells into eyes boosts vision in blind mouse models
Scientists studying engineered biomaterials at the University of Toronto (UT), Canada, have happened upon a technique that could one day treat blindness – they demonstrated how a new method of injecting healthy cells into the eyes could address vision loss similar to conditions like age-related macular degeneration (AMD) or retinitis pigmentosa.
Both conditions see the deterioration of the photoreceptor cells and another type known as retinal pigmented epithelium (RPE) cells at the back of the eye. “RPE and photoreceptors are considered as one functional unit – if one cell type dies, then the other one will too,” said UT Professor Molly Shoichet. “We wondered if co-delivery of both cell types would have a bigger impact on vision restoration.”
The UT team loaded up hydrogels with photoreceptor and RPE cells to be injected into the eyes of severely blinded mice. The hydrogel is viscous enough to ensure a good distribution of both cell types and also has important shear-thinning properties to facilitate injection through a very fine needle point.
The team found that the mice injected with both cell types regained around 10% of their normal vision acuity, compared to mice which received just one of the two cell types and showed little to no improvements. In behavioral experiments, these mice were also more active in dark chambers.
The promising results of the co-injection treatment have the scientists excited, with cautious optimism. No other experiment has attempted to combine these two cell types into a singular treatment, but the team still needs to demonstrate the benefit of this strategy in multiple animal models.
“We’ll also need a source of human photoreceptor cells and a way to further improve cell survival, both of which we’re working on,” Shoichet added.