They are growing human corneal endothelial cells in laboratory cultures with the ultimate goal of transplanting them into patients. Their studies show promise for complementing, perhaps even supplanting, the conventional corneal transplant procedure, according to David Hwang, MD, a UCSF associate professor of ophthalmology. Employing the latest in cell culture and gene therapy technologies, the UCSF scientists are achieving results that, theoretically, could overcome all of the limitations of current corneal transplantation, he said. The team hopes to begin performing human cell transplantation within the next three to five years. Hwang outlined the UCSF research at a media briefing held yesterday in conjunction with the American Academy of Ophthalmology annual meeting in San Francisco.
Corneal disease is characterized by blurred vision or blindness stemming from damage to the cornea.
This delicate, transparent eye tissue covers the iris and pupil and serves as the transparent window through which light is transmitted and focused on the retina. Causes of the condition vary, from congenital abnormalities that affect thousands of newborns each year, to trauma in industrial workers and sports participants, eye infections in contact lens wearers, and complications resulting from cataract surgery in older individuals. When damage is severe, surgical replacement of the cornea with a transplant may be necessary. Corneal transplantation is often required for treating the disease because the corneal endothelium, a delicate layer of cells in the cornea that is the prime site of injury in the tissue, cannot replace or repair itself. In the UCSF research, human corneal endothelial cells have been grown in laboratory cultures, and the researchers have induced the cells to divide as many as 20 to 4000 times without slowdown.