March 25, 2003
"The interaction between clinical and basic science has been interesting," said David Jansen, chief of plastic and reconstructive surgery. "I always want big results and instant gratification, but basic scientists are more interested in the process."
Jansen has spent the last five years working with Kim O'Connor, a tissue engineer and professor of chemical engineering, to develop a method of growing fat in the laboratory for use as a filler in plastic and reconstructive surgery. Currently, fat from a woman's own body is often used in reconstructive surgery after a mastectomy, for example. But that requires a long surgery with many possible complications.
"Our goal is to have a bank of tissue available," Jansen said. "If we could have something that's essentially off the shelf, that would be ideal."
There is a precedent for this in lab-grown skin tissue used for grafts on burn victims. The fat would be grown on a bio-absorbable scaffolding, so that the implant would eventually be indistinguishable from the tissue around it. Jansen went to a tissue engineering conference to explore the possibility of developing such an implant. There he was informed that Tulane had an expert in growing the kind of three-dimensional cell cultures needed.
"I said, 'Gee, that would be convenient,'" said Jansen.
O'Connor had been studying prostate cancer before she met Jansen, but was looking for the opportunity to work on a non-malignant system. The two came up with an idea for a way to approach the problem and were able to obtain funding from the Joe W. and Dorothy Dorsett Brown Foundation. The pair have succeeded at growing natural fat cells, no different from those in the body.
For raw material they used fat donated by Jansen's patientsgraduate students actually came into the operating room to pick it up, since it needed to get to the lab quickly. A cell-culture facility was set up in the surgery department so the tissue wouldn't have to travel uptown. The first paper on the project was published in Tissue Engineering, the leading journal in the field, and has received a great deal of attention from the local press, although Jansen estimates it will be a decade before they will have living tissue ready for clinical use. But there have already been significant successes.
Jansen and O'Connor have developed a method of projecting the growth rate of fat, which can be used to predict whether patients are good candidates for augmentation with their own tissue--thereby helping to avoid complications like infection, tissue damage or tumors. And this system of modeling and predicting behavior of cells also suggests a whole new approach to tissue engineering, according to O'Connor.
"With a small quantity of cells, we can do a variety of things simultaneously," she said. "That's where mathematical modeling comes in; it allows you to come up with logical steps to evaluate parameters."
It was for his work in developing this approach that Hong Song, a graduate student in chemical engineering, won the Outstanding Graduate Student Award from the American Institute of Chemists Foundation. And O'Connor won the Tulane Interdisciplinary Teaching Award in 2001 for the opportunity she gave her students on this project to cross boundaries they would not otherwise have been able to breach. The project could not have happened without collaboration between clinicians and basic scientists, but such interaction can be challenging on all sides.
"People feel comfortable working in their own area. It takes a lot of effort to jump the void," O'Connor said. "I had to learn to see things from a surgical perspective, and I don't know if David expected to be looking at differential equations."
"The hard part is solving problems with no references," Jansen said. "There's a lot of people out there trying to grow fat, but there's not a lot of experience we can rely on." Instead, through trial and error, Jansen and O'Connor themselves are becoming the experts.
Heather Heilman can be reached at firstname.lastname@example.org.
Tulane University, New Orleans, LA 70118 504-865-5000 email@example.com