Specialized Scaffolding

(Photo by Duane Zehr)

Additional images

August 19, 2014

By Nancy Ridgeway

The word “scaffold” conjures images of a building construction site, but a new kind of scaffold created by a Bradley mechanical engineering professor and her student assistants is playing an integral role in stem cell research.

Dr. Kalyani Nair, associate professor and coordinator of the biomedical concentration in mechanical engineering, is collaborating with Dr. Craig Cady, associate professor of biology and director of Bradley’s stem cell research laboratory, to create a scaffold with an environment that encourages cord blood stem cells to grow into specific kinds of cells.

The scaffold temporarily acts as a supporting structure for stem cells to attach and differentiate into specialized cells, tissues and eventually organs. The scaffold also helps contain the cells, which are otherwise prone to dispersing once injected into the body. Over time, the scaffold deteriorates, but the new cells remain and form functional tissue.

By encouraging stem cells to grow into particular kinds of cells and to remain where they are needed, Cady and Nair hope patients will benefit with more effective treatments in the future.  

Cady said, “I’ve done stem cell research for quite a long time. I was not a nanofiber material person, but across the quad, Dr. Nair has that experience. She and her students produce the material for us. We grow stem cells on the material, then analyze them as they grow and develop. We’re trying to grow brain cells for Parkinson’s Disease research.”

In fact, Cady’s goal this summer is to create brain cells on the scaffold and verify through a variety of tests that the stem cells are taking on the properties of brain cells.

“It took us a long time to find the right material, but this material seems ideal,” Cady said. “It’s a nice collaboration because whenever we need material, they can make it. They test the nanomaterial for strength and all the factors we don’t handle in my lab, and then we focus on the stem cells.”

Nair uses a process called electrospinning to create the micro-weave scaffold structures made of polymeric nano-fibers. The process is versatile in the use of different fibers, can easily be controlled to fabricate fibers with a wide range of diameters, allows for high porosity and is cost-effective.

“Each fiber can be aligned in a different way,” Nair said.  By controlling the material’s stiffness, porosity and other properties, she can create a foundation for the stem cells to thrive and grow into the kind of cells needed.

“The stem cells are capable of sensing their local environment and becoming a specific type of cell,” said Nair. “If you want a nerve cell, we provide a certain stiffness; if you want a bone cell, we provide a different stiffness. We can add growth factors into the scaffold, too.”

Discussing the scaffold Nair has created, Cady said, “Most of the nanomaterials look random, but the fibers [on these scaffolds] are parallel just like in the brain. The fibers are so small that you look at them with an electron microscope.”

Cady implants a “cocktail” onto the scaffold consisting of various chemicals such as valproic acid to encourage stem cell growth along with thousands of stem cells on a scaffold that measures about a half a centimeter. A small drop of the cocktail the size of a pinch of salt could cost about $350.

 “The fluid is in a syringe about the size of my thumb and is put on a special device with a precise amount of pressure. The fluid is streamed onto the material in a very fine mist. Over time, you can see it start to deposit on the target,” Cady said.

Cady and Nair collaborate with Caterpillar, Southern Illinois University-Springfield and the National Center for Agricultural Utilization Research. The collaboration allows for the use of expensive equipment and resources that would otherwise make the research cost-prohibitive at Bradley. In addition, Cady and Nair’s students have an opportunity to work with professionals at these institutions, furthering their experiences, as well. The professors along with mechanical engineering students John Dougherty and Emily Schaefer, biochemistry major Ryan Niemeier ’15 and biology major Erin Koch ’15 presented a paper on their research at the 2013 International Mechanical Engineering Congress and Exposition last November in San Diego.

Cady appreciates private funding from the Don Bolander Parkinson’s Foundation, Dr. Arthur and Bonnie Ennis Foundation, and Dr. Norman and Brenda Johnson.  

Nair said finding a colleague on campus who can benefit from her nanofiber research is a valuable dimension of her work at Bradley.

Cady added, “This is an exciting field. No one has researched these cells for this application.”