Researchers Are Developing ‘Living Eye Drops’ Designed to Heal the Cornea. Here’s How They Work
Researchers are developing experimental eye drops made from living bacteria that could heal corneal injuries with a single application. Here is what to know about the science behind these “living eye drops” and how they might change treatment for millions of Americans.
What Are the New Living Eye Drops Being Developed for the Cornea?
The “living eye drops” are an experimental therapy that uses a genetically modified, naturally occurring eye bacterium to deliver an anti-inflammatory protein directly to the cornea. Researchers at the University of Pittsburgh School of Medicine engineered the harmless eye-dwelling microbe Corynebacterium mastitidis to secrete interleukin-10 (IL-10), a protein that regulates inflammation and supports wound healing.
The proof-of-concept study was published in Cell Reports in March 2026. In mouse trials, corneas that were gently scratched and treated with the engineered bacteria healed faster than those treated with regular bacteria or saline, according to the University of Pittsburgh. When the IL-10 receptor was blocked, the benefit disappeared, confirming the effect was IL-10-dependent.
How Do Living Eye Drops Work Differently Than Regular Eye Drops?
Unlike standard eye drops that get washed away by tears within minutes, living eye drops use bacteria that colonize the eye and continuously release therapeutic proteins after a single application. The microbe lives under the eyelid and keeps producing the anti-inflammatory protein over time.
“This is the first demonstration that a microbe that lives on the ocular surface could be engineered to deliver a therapeutic that improves eye health,” said Anthony St. Leger, associate professor of ophthalmology and immunology at the UPMC Vision Institute and senior author of the study. “It opens the door to the idea of ‘living medicine’ for the eye, something you apply once, and it stays, protects and helps the tissue heal.”
Current treatments for conditions like corneal abrasions or dry eye disease often require multiple drops per day, a regimen that can reduce patient compliance and limit effectiveness.
Could These Eye Drops Treat Dry Eye and Other Cornea Conditions?
The technology could eventually treat corneal injuries, severe dry eye disease and other inflammatory disorders of the ocular surface, though it has not yet been tested in humans. Traumatic ocular surface injuries alone affect more than 1 million Americans per year, according to the study published in Cell Reports.
Researchers also created a version of the microbe that releases human IL-10, which improved wound closure in lab-grown cells from the outer layer of the human cornea and reduced inflammatory signaling in human immune cells. The system is also designed to be modular.
“We built it so you can swap in different genes, different cytokines, growth factors or other proteins, to tailor the therapy to specific eye diseases,” St. Leger said.
When Will Living Eye Drops Be Available to Patients?
Living eye drops are not yet available and remain in early-stage research, with substantial development required before human clinical trials can begin. Researchers still need to determine how to deactivate the protein once treatment is no longer necessary.
“More research is certainly needed, particularly to determine how to deactivate the protein once treatment is no longer necessary,” St. Leger said, per UPMC. “But the findings in this study are promising, and could open the door to the development of ‘living’ medications for a range of vision conditions.”
The researchers describe the work as a proof of concept that opens the possibility of harnessing the ocular microbiome to treat eye diseases, rather than a finished clinical therapy.
This article was created by content specialists using various tools, including AI.
