AN EYE FOR EYES: Tonia Rex, who recently began work at UTHSC's Hamilton Eye Institute, is working on a way to treat degenerative blindness that also could help patients with Parkinson's or Alzheimer's diseases. -- Photo By Scott Shepard

When the retina does not get enough of a protein known as Epo, it can lead to degenerative blindness, but scientist Tonia Rex has a strategy to stop that disease in its tracks.

And since the eye is part of the brain, her biotechnology also might be useful in treating Parkinson's and Alzheimer's diseases, and even strokes. She foresees the day, perhaps 10 years from now, when these and a number of other neurological ailments can be treated with a single shot in the hip.

Rex is the newest addition to the faculty at Hamilton Eye Institute, the ophthalmology center at the University of Tennessee Health Science Center. After completing her doctorate degree at the University of Pennsylvania in Philadelphia, Rex was actively recruited by three centers but chose UT because of the caliber and reputation of the people already on staff and the opportunity to collaborate with them.

"I've been wanting to pursue other areas of neuro degeneration," she said. "The attraction of Hamilton is also the close interaction with clinicians. I want to work closely with them."

Buying time

Previously Rex worked in the lab of ophthalmologist Jean Bennett, a professor of cell biology at the University of Pennsylvania, or Penn. Work there centered on using gene therapy to treat retinal degeneration. In gene therapy a healthy gene is attached to a virus using the virus' unique ability to bore into a cell and deliver the payload.

Rex uses a virus engineered so it produces no immune response when injected into a muscle. That's important because the goal is to coax muscle cells into manufacturing a steady stream of Epo, which then enters the blood stream and is used where needed. Rex has already had promising results in mice.

Rex is building on that work to deliver a gene that produces Epo. Her work centers on halting the degradation of the retina, but other UT scientists want to adapt it to their work:

Eldon Geisert is a professor of ophthalmology, anatomy and neurobiology who sees huge potential for gene therapy in treating glaucoma.

Professor Thad Nowak is director of UT's Neurology Research Laboratories and wants to adapt Rex's technique to treat stroke.

Michael McDonald, an assistant professor in the neurology department, said he believes Rex could have a potent treatment for Parkinson's, Alzheimer's and other neurological diseases.

"This is not a cure, but it will stop further cell death," Rex said. "A cure would correct the underlying condition. If we can demonstrate that it's safe, then we can slow progression of the disease, which gives us more time to find a cure."

The goal is to develop a treatment for people with an active disease; a person with early signs of Alzheimer's could be stabilized. But Rex doesn't mind speculating long term; if the treatment proves effective it someday might be approved for people with a high risk of
neuro disease, sort of an Alzheimer's inoculation.

'Impressive pedigree'

The $66 million Hamilton at 930 Madison Ave. has research labs and clinics on contiguous floors so medical doctors and scientists are just two flights of stairs away from one another. The design was created by ophthalmologist Barrett Haik, chairman of the department and chief of ophthalmology at St. Jude Children's Research Hospital. Putting the scientists and the physicians in close proximity speeds research and innovation, he said, and also reminds researchers that there is a suffering patient waiting for their work.

"We are entering the most promising time for scientific discovery, and cures for blinding diseases are within reach," Haik said. "Advances in neurobiology, molecular genetics, microbiology and immunology have converged, making gene therapy a reality."

Recruiting Rex was a team effort, Haik said. Others on the faculty discussed the skills and knowledge that would best enhance the work at Hamilton, with Rex filling the bill.

She turned down offers at both Cleveland Clinic and the well-funded Howard Hughes Medical Institute at the University of Iowa.

"Everyone says I have an impressive pedigree, which makes me feel a little like a show dog," she said. "Iowa was tempting because they have a vector core, but we're getting one too, at the cancer center."

A gene transfer vector core is a lab designed and equipped specifically for engineering viruses in support of gene therapy research. Sharing it with the UT Center for Cancer, Haik said, is an example of the direction research is moving, with different disciplines sharing ideas and hardware.

"This team approach is critical to major scientific projects that require expertise in multiple areas and expensive, shared resources," he said.

A woman of vision

Rex concedes she is a pure academic person, and has not given much thought to the business potential in her work, though she understands that a treatment for Alzheimer's has the potential for changing the world and making bales of money.

Some preliminary studies also show that her treatment could have a role in treating heart disease by bolstering the nervous system there, opening other business opportunities.

"I'm an academic, and I'm not interested in making money," she said. One possible scenario would be to have an experienced businessperson run the business with Rex serving as the knowledgeable public face of the company.

"I strongly feel that God brought me here to do good science that helps people," she said. "The work I'm doing, and the work of the other people here can mean giving people a few more years to see the people they love."