Home - Improving Implants – Spring 2010
They’ve never performed surgery. They’re not bioengineers. But University of Maine undergraduate students Kara West and Amy Foley are hoping to make a difference in the medical world by exploring the use of cells as therapeutic agents for repairing damaged tissues — an alternative to conventional surgical therapies and implants.
Working under the direction of UMaine mechanical engineer Alireza Sarvestani, the students are investigating how to repair dysfunctional tissues by mimicking the way the body produces cells. The hope is that implants using stem cells infused with polymeric biomaterials could someday take the place of artificial implants.
“The application of cell-seeded biomaterials for regeneration of damaged tissues is not new. What we are trying to do in our lab is to optimize this process, which is currently based on the principle of trial and error,” says Sarvestani, whose research interests include the biomechanics of cell adhesion and locomotion.
The bioengineering research at UMaine, which uses bovine cells as models of human cells, focuses on implants made of bioresorbable materials instead of permanent implants that can sometimes be rejected by the body. The technology could be particularly helpful in repairing cardiac endothelial tissue in patients who have experienced heart attacks or other cardiovascular-related damage, Sarvestani says.
“The (current implant methods) are permanent, but not good because they are not part of your body,” says Sarvestani. “In our project, host stem cells take over and the implant — the polymeric material — begins to degrade (when it comes in contact with water). As the stem cells proliferate, the implant will essentially go away.”
In Sarvestani’s lab, the bovine cells are injected with the polymeric material and grown in vitro to mimic the way similar cells would function and grow in humans. The goal is for the host stem cells to take over and form new tissue concurrent with degradation of the biomaterial implant, leaving the repaired host tissue in its place.
Sarvestani is focusing on the project’s mathematical portion — the formulas that help determine the optimized chemomechanical characteristics of polymeric material to use. And he’s investigating how the materials react with their environment — in this case, the human body.
Foley, a biochemistry major from Deer Isle, Maine, is focusing on the organic chemistry of compounds and processes occurring in organisms. West, a computer science major from Brentwood, N.H., is electronically documenting and analyzing the process and structure of their research. Both now plan to pursue medical school.
By studying the mechanical properties of the cells and how they respond to stimulus, which is more about biology than engineering, Sarvestani thinks the outcome could be extremely effective in practical surgical situations.
Sarvestani’s tissue engineering principles have the potential to be applied to many types of human tissue, as well as bone and cartilage. Although the project is still in its early stages, he hopes that the upcoming results will draw the attention of medical centers in Maine for future collaborations.
“Certainly when we’re done with this part of the study, we would like to do more realistic testing,” he says. “We’d like to be able to make the implants and try them in a real-life situation.”