PEDF, protein that inhibits blood vessel growth in the eye, is licensed as possible gene therapy candidate to prevent blindness

An eye protein that blocks excessive blood vessel growth will be developed as a possible candidate for gene therapy to prevent blindness in individuals with macular degeneration and diabetic retinopathy. The protein, pigment epithelium-derived factor, or PEDF, has been shown to halt angiogenesis in an animal model with an eye disease similar to human diabetes-related blindness.

Noel Bouck, professor of microbiology and immunology at the Northwestern University Medical School, who discovered the use of this protein in inhibiting angiogenesis, said PEDF may have important therapeutic implications in diabetic retinopathy and macular degeneration, the leading cause of blindness in the Western world.

Bouck�s research also has shown that PEDF may have therapeutic potential in the treatment of cancer. GenVec, Inc. obtained an exclusive license to PEDF from Northwestern University for all ocular gene therapy applications. This license covers methods invented by investigators at the University for inhibiting abnormal blood vessel formation that leads in blindness in patients with macular degeneration and diabetic retinopathy.

The University currently is in discussions with other companies to develop other applications for PEDF using differing technologies.

Bouck and her laboratory group, who also are researchers at The Robert H. Lurie Comprehensive Cancer Center of Northwestern University, recently demonstrated that administration of PEDF prevents excessive new blood vessel formation in an animal model of retinopathy.

An article describing their findings appeared in the Jan. 23 online edition of the Proceedings of the National Academy of Sciences.

In earlier research, Bouck and associates found that PEDF prevents blood vessels from entering two compartments of the eye through which light must pass � the cornea and the vitreous � thus helping to ensure clear vision.

They also found that the amount of PEDF produced by retinal cells is regulated by the amount of oxygen present, suggesting that a decrease in inhibitory PEDF provides a permissive environment for ischemia-driven angiogenesis in the retina that occurs in diabetic retinopathy.

Many diseases associated with vision loss, such as diabetic retinopathy and macular degeneration, are caused when poor oxygen supply to the eyes causes new blood vessels to proliferate and block the light-sensitive retina.

Bouck�s co-researchers on this study were Veronica Stallmach, post-doctoral student, pathology; and Susan E. Crawford, assistant professor, pathology.