Biomaterials for bodies

By Pamela Wyngate
HS News & Community Relations

It may not be nice to fool Mother Nature, but some UW researchers are hoping to do just that. In 1996 the UW Engineered Biomaterials (UWEB) program began as a collaborative effort to incorporate basic molecular biology into the development of more effective medical implants.

“The body detects surgically implanted medical devices as foreign objects,” says Dr. Buddy Ratner, professor in the departments of bioengineering and chemical engineering and director of the Center for Engineered Biomaterials. “The healing process is its natural defense.”

Buddy Ratner in his lab, where he and colleagues in the UW Engineered Biomaterials (UWEB) program work on novel solutions to implant rejection.

Ratner works with the over 25 primary investigators including materials scientists, biomolecular engineers, physicians and molecular biologists. Recent UWEB research has included work in cell physiology to elucidate the key molecules and events involved in healing. Proteins such as thrombospondin, osteopontin and SPARC are particularly critical to wound healing. Cells secrete these proteins to turn the inflammatory process on or off.

“Once we understand what role these proteins play in the healing process, we want to exploit their chemical constituents in some kind of surface treatment for biomaterials, to control inflammation,” explains Ratner.

Biomaterials are the substance of synthetic devices that are surgically implanted in the body to replace or augment an organ or bodily function. Arterial stents, intraocular lenses and breast implants are all composed of biomaterials.

For example, each year intraocular lenses are an effective treatment for 7 million people with cataracts, according to Ratner. Possibly as many as half of those people require re-operation because the implant-the lens itself-stimulates epithelial cell growth. Tissue envelops the medical device in a scar-like capsule. Control of the inflammatory process may allow us to address problems such artificial lens healing and develop a generation of medical implants with much lower complication rates.

“When the body puts scar tissue around an internal medical device, the performance of the device goes downhill until eventually it may not work at all,” says Ratner. “If we could reduce the magnitude of the inflammatory response, these devices would be much more effective.”

Ratner presents the Science in Medicine Lecture “The Next Generation of Implant Materials: Biomaterials that Heal,” Thursday, Feb. 15, at noon in T-733 Health Sciences Center.

In 1972 Ratner received his Ph.D. in polymer chemistry from the Polytechnic Institute of Brooklyn, N.Y. From 1970 to 1972 he also held a National Institutes of Health traineeship. After earning his Ph.D, Ratner joined the UW Department of Chemical Engineering as a postdoctoral fellow. In addition to his UW appointments, he is president-elect of the American Institute of Medical and Biological Engineering.