Carnegie Mellon University
December 16, 2014

Carnegie Mellon's Adam Feinberg Develops Key Method for Manipulating Cells in Engineered Tissues for Medical Devices

By Daniel Tkacik 412-268-1187

Carnegie Mellon University Professor Adam Feinberg and his colleagues have developed a new method to control how cells organize themselves on surfaces, a key process required for building and interfacing muscle tissue with medical devices such as coronary stents. The results were published in this week's issue of Nature Methods.

"In order for muscle to contract with maximum force, you need to have all the muscle cells aligned in the same direction," explained Feinberg, a professor in CMU's Department of Biomedical Engineering. "By micro-patterning adhesive proteins on a surface, we can guide cells to align all together, regardless of the underlying roughness or topography."

While scientists have been able to manipulate surface cells by micro-patterning either the adhesive proteins that interact with the cells or the topographical features, i.e., pillars and ridges which force cells to grow in specific directions, Feinberg said it has been challenging to combine both techniques together.

"To micro-pattern proteins, researchers have used a contact printing technique; imagine a rubber ink stamp," Feinberg explained. "If you place a rubber stamp on a rough surface, only the top of the rough features will touch the stamp, leaving holes and gaps in the pattern."

To address this problem, Feinberg's group created a technique termed "Patterning on Topography" that is able to reach into deep areas on rough surfaces, allowing more of the proteins to be transferred. To do this, the group first micro-patterned proteins onto a special polymer that swells when it is placed in warm water and then cooled. This swelling behavior was used to transfer the patterned protein.

"In Patterning on Topography, the release surface swells with water and pushes the protein into all the nooks and crannies on the rough surface," Feinberg explained. "We realized that the proteins were stretchy, and that they could be patterned in this new way with high fidelity, even into deep holes."

Feinberg said their work opens the door for countless new studies.

"The novelty here is the ability to combine micro-patterned chemistry and topography in new ways to control cell growth and behavior," Feinberg said. "Currently, we are using this to understand more about how cells behave, but ultimately we plan to use Patterning on Topography to engineer heart muscle and to enhance the biocompatibility of medical devices, such as improving the long-term stability and performance of coronary stents."

This research was supported by the National Heart, Lung and Blood Institute of the National Institutes of Health under Award Number DP2HL117750. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.