Researchers from the University of Alberta in Canada have developed a method of ‘laser welding’ neurons, which could potentially lead to a new, more effective way to treat damaged or severed nerves.
Neurons are cells in the nervous system that transfer information between the brain and the rest of the body, connected to each other at junctions called synapses. Synapse junctions are insulated by a fatty substance called myelin, which protects neurons and increases the speed at which electrical signals are transferred between them.
If this myelin sheath becomes damaged, or any part of the nerve is severed, this transfer of information is impeded or halted, which can lead to health conditions such as paralysis. Mature neurons do not divide, so they are unable to heal themselves once damaged, which is why damaged nerves are so hard, and take an incredibly long time, to treat.
‘You have a severed nerve, you can't repair it. My thought was, what if we could “weld” it back up right after it's injured?’ said Nir Katchinskiy, a second-year PhD student in Electrical Engineering who led the study.
The team from the University’s Faculty of Engineering has been the first to find a way to bond neurons, according to a paper that has been published in Nature Scientific Reports.
The researchers first brought two neurons – that were put in a special solution preventing them from sticking together – into contact with each other. Femtosecond laser pulses – each ultrashort pulse occurring every 10-15 seconds – were delivered to the meeting point of the two cells. Although the outside layer of the cells was partially compromised, the inside of that protective layer remained intact. As a result, the two cells established solid bonds forming a common membrane at the targeted area.
Throughout multiple experiments, the cells remained viable and the connection between the cells was strong. It took the neurons 15 milliseconds to stick to each other; a process that would have taken hours to occur naturally.
The biggest advantage of the discovery, according to the scientists, is that it gives researchers complete control on the cell connection process, allowing them to conduct research into the nervous system more effectively. ‘You can really plan any experiment. The idea is to show that you can use it [a femtosecond laser] as a research tool to control what you are attaching,’ explained Katchinskiy.
‘You may not be able to go in and treat the human spine with this, but it brings you closer… to how these things work,’ said electrical engineering professor Abdul Elezzabi, who is a co-author of the paper.
So far, the team has applied this method to three types of cells, but the potential of the technique spans beyond studying the nervous system, to aiding prostate, brain and ocular cancer research and treatment.