Graduate students at the University of Wisconsin, Madison, report that they've successfully managed to get nerve cell tendrils to grow through tiny tubes made of semiconductor materials.
The ground-breaking research could one day be used to regenerate nerve cells damaged due to disease or injury, and possibly lead to advances in nanomedicine, including improved brain-computer interface (BCI) technology.
How did they do it? Led by Minrui Yu, a graduate student, and Justin Williams, a biomedical engineer, the UW-Madison team first created tubes of varying sizes and shapes made out of silicon and germanium. The tubes closely resembled myelin (both physically and electrically), the outer insulating sheath that covers parts of normal nerve cells. The tiny tubes were small enough for a nerve cell to grasp on to, but not so big that it could fit all the way inside.
The team then coated the fabricated tubes with nerve cells from mice and carefully observed the reaction. Instead of sitting idly, the nerve cells began to send tendrils through the tunnels, as if searching for a path to something or somewhere else. In some cases the nerve cells actually followed the contours of the tubes, meaning that the nerves could be grown into structures, at least in theory.
It is common knowledge among neuroscientists that nerve cells have a seek feature, but they aren’t yet sure what it is that the cells are seeking or if the behavior is just random. To help find the answer, the team plans to set up nerve cells to follow pre-planned paths through tiny tubes and use listening devices to record electrical emissions or "conversations" between the cells.
The team hopes that this approach can lead to a way to connect a computer of some sort to a group of nerve cells to reestablish communication that has been disrupted. The computer in this case could serve as a relay of sorts, allowing those who can no longer walk or see, for example, due to injury or disease, regain their former abilities.
Researchers have been exploring nanotechnology to help regenerate nerve cells for years, with approaches ranging from the use of magnetic nanoparticles (MNPs) to help stimulate the growth of axons of the central nervous system, to the use of aligned nanofibers or scaffolds where nerve cells can regrow.
The UW-Madison research is published in ACS Nano: Semiconductor Nanomembrane Tubes: Three-Dimensional Confinement for Controlled Neurite Outgrowth.