Harvard University researchers have developed an engineering technique to precisely control the direction that neurons grow their axons, cable-like structures that allow nerve cells to connect with each other. In a zebrafish model, researchers used the approach to correct defective neural connections and restore the neuron’s ability to cause muscle contractions.
The findings, published in the journal Developmental Cell, represent a key step toward repairing nervous system damage in patients. They may also enable scientists to create more accurate models of the brain in a lab dish, by instructing the formation of precise neuronal connections resembling those of the actual brain.
“The process of establishing connections between neurons mostly occurs during embryonic development, especially in mammals like us. After that point, if these connections are severed in situations such as spinal cord injury, the neurons typically do not regrow their connections, losing functionality. It would be a great achievement to be able to overcome these difficulties,” said Paola Arlotta, the Golub Family Professor of Stem Cell and Regenerative Biology. “This study is a proof of principle that shows the potential of a noninvasive strategy to direct neuron growth.”
Forming connections
A neuron’s axon is a projection that emanates from the cell body and connects to other cells, often located a great distance away. In the developing embryo, a complex set of signals guide a specialized structure at the tip of the axon, called the growth cone, to its precise target to wire the nervous system.