It's sticky, it's a gel, it comes in a tube, but this is no greasy kids' stuff. Rather, it's a novel delivery system for peripheral nerve regeneration that could have implications for successful stem cell delivery and spinal cord repair.
Shelly Sakiyama-Elbert, Ph.D., assistant professor of biomedical engineering at Washington University in St. Louis, has designed a system that employs a nerve guide tube filled with a gel containing growth factor proteins that stimulate nerve regeneration. Also part of the package are strategically placed sugars and peptides for binding in the gel matrix. The system has promoted peripheral nerve regeneration in preliminary rat studies.
The clinical Gold Standard for peripheral nerve regeneration involves taking a nerve from a donor site on the injured person's body and sewing the donor nerve in between the two ends of the injured nerve. Though the nerve is dead, it provides a pathway that can guide the regeneration of the injured nerve. This is problematic because it creates an injury to be addressed at the donor site, and there is a limit to the amount of donor tissue you can use from a patient. Furthermore, there is no guarantee that the donated nerve will come to life in a new site. Another alternative is the use of cadaver nerves, which runs a risk of rejection.
Sakiyama-Elbert, working with famed plastic surgeon Susan Mackinnon ,M.D., Syd. M. and Robert H. Shoenberg Professor of Surgery of the Washington University Medical School, places exogenous sticky material capable of binding growth factors throughout the gel, causing the growth factor proteins to remain in the gel for months because they keep tripping over the sticky material. These binding sites can be tuned according to how fast the drug needs to be released for successful regeneration. Timed release is a key component of her system, because a real limitation is having the proteins diffuse out in a day or two, which is the case with man
Contact: Tony Fitzpatrick
Washington University in St. Louis