Potentially blinding blood vessel growth in the cornea resulting from eye injury or even surgery can be reduced by more than 50 percent with a new manmade protein, researchers say.
"We believe eventually we'll be able to use this protein to help patients in many situations where blood vessel formation is detrimental, including cancer, diabetic retinopathy and macular degeneration," says Dr. Balamurali K. Ambati, corneal specialist at the Medical College of Georgia and Augusta Veterans Affairs Medical Center. Dr. Ambati is corresponding author of the study published in the November issue of Investigative Ophthalmology & Visual Science.
The body can produce new blood vessels to promote healing after trauma, such as a corneal transplant, a significant corneal scratch from a contact lens or retinal oxygen deprivation caused by diabetes or aging. This natural response, called angiogenesis, becomes detrimental when new growth obstructs vision or when a tumor pirates the process to survive.
In an animal model, researchers used the protein they developed to reverse obstructive growth as long as one month after injury, says Dr. Ambati. That's a very long time after injury in a mouse's lifetime, indicating even well-established blood vessels are susceptible to intraceptor-mediated regression, he says.
This intraceptor traps vascular endothelial growth factor, or VEGF, inside the protein making machinery of a cell. It's made with a portion of a VEGF receptor called sflt-1, a free-floating receptor recently shown to help keep the cornea clear by taking up and effectively neutralizing VEGF. Although other molecules have an anti-angiogenic effect, sflt-1 was the only one they found that spurs corneal blood vessels when blocked. The work, published in October in Nature, was led by teams at MCG and the University of Kentucky.