AMES, IA — Under a whirring cell culture hood at Iowa State University, two undergraduate students look at something resembling a tiny, white bone in a petri dish. Abigail Fowler, a senior majoring in microbiology, points to the cut ends with a tweezer.
“You can see those little channels that nerves would travel through. Some of these gelatin scaffolds have channels or microstructures that are larger, more symmetrical than others,” says Fowler.
She shows Bridget McGovern, a sophomore in biology, how to pipette a solution with neural stem cells onto the edge of the gelatin scaffold and then places the petri dish in an incubator set at the same temperature as the human body.
After three days, Fowler will teach McGovern and other undergraduates in the Sakaguchi Lab how to measure cell growth.
“One of the projects in our lab is trying to determine which scaffolds are best designed to stimulate nerve regeneration. If patients are severely injured from a car accident or blast event and are missing a segment of a peripheral nerve, the devices that we’re investigating could serve as a bridge to guide regenerating nerve fibers across that gap,” says Don Sakaguchi, a Morrill Professor of genetics, development and cell biology, director of ISU’s biology and genetics undergraduate programs, and a member of ISU’s Nanovaccine Institute.
Peripheral nerves, which are outside the brain and spinal cord, can grow back after most injuries. But the process is slow and without a signal or structure to help guide them, the nerve ends up and forms scar tissue, Sakaguchi explains.
People with traumatic damage to peripheral nerves may experience a loss of muscle control, as well as severe pain, burning sensations, tingling, or numbness in the area affected by the injury. To relieve their symptoms, around 700,000 people in the U.S. each year undergo surgery.
Currently, the most effective procedure for a severe injury, such as a missing segment of a nerve, is an autologous graft, says Sakaguchi. A surgeon cuts out a section from an intact nerve from the patient and grafts it to the site of injury. However, this process has low success and can create long-term nerve damage at the donor site. Multiple surgeries also increase the risk of infection. The different variations of gelatin scaffolds being tested in Sakaguchi’s lab have not yet been used in humans. They were created by his research collaborators at the Izmir Institute of Technology in Turkey with a novel technique they developed. The highly enriched collagen gels give the structures flexibility and allow them to degrade over time, which Sakaguchi says would be important during the healing process.