Nanoparticles Curtail Rejection of Corneal Transplants in Lab Studies

Researchers at the Center for Nanomedicine have developed tiny particles smaller than 100 nanometers in size — or 1,000 times smaller than the thickness of a newspaper page — that have successfully preserved corneal transplants in mice.

Published in Insight - June 2015

“We are excited about this technology and the potential it has to receive funding to go into a clinical trial,” says Justin Hanes, director of the Center for Nanomedicine at the Wilmer Eye Institute. “Medication is released uniformly over time from tiny particles made of biodegradable plastics.”

Eye disease specialist Walter Stark worked with Hanes and his team to create the drug-eluting nanoparticles that stay in place when injected to slowly and steadily administer medication. In preclinical animal studies, the innovation was 100 percent effective.

All the animals treated with the therapy once a week for nine weeks had clear corneal transplants. All those that did not receive the treatment eventually rejected their transplants.

In people, 10 to 20 percent of the 40,000 corneal transplants that take place each year are rejected. The cornea is the clear, dome-shaped surface that covers the front of the eye; injuries or diseases to it can cause blindness.

One reason for the high rate of rejection is that patients aren’t using their eye drops as prescribed. Traditional therapy requires eye drops every hour or two during the first week after surgery, and then at regular intervals for a year or longer.

The ultimate goal of the new technology is to inject the nanoparticles in patients’ eyes during surgery for a corneal transplant so they do not need to take eye drops as frequently after surgery. The slow release of medications over time avoids the problems of poor medication compliance, which happens in up to 80 percent of patients.

Researchers are using the same type of drug delivery system for other conditions, such as glaucoma and macular degeneration.