WASHINGTON — Engineers and biologists at McMaster University in Hamilton, Ontario, have succeeded in coaxing tiny worms to move around a microchip using electric fields. This should help neurologists study the human nervous system.
The worms, called C. elegans, are one of the mainstays of neurological research. That’s because the worms, with only a few hundred neurons, have a simple nervous system. In the new McMaster experiment, the worms are coaxed into starting and stopping, pretty much on command.
“This technique provides us for the first time the ability to communicate with the worms and make them do a certain task” said Ravi Selvaganapathy, an engineer at McMaster. “For instance, we could expose the worm to a drug and quantitatively measure the speed of the worm and compare it to unexposed worms.”
Previously worms could be made to move, but not in any reliable, repeatable way. Getting the worms to move in a definite way gives scientists a chance to be more precise in measuring the effect of various toxins or remedies.
C. elegans worms are used to study human illnesses because 60 percent of the genes in their cells have a human equivalent. They can suffer conditions similar to human diseases such as Parkinsonism and Huntington’s diseases. In the worms’ accelerated lifespan these diseases can play out in days rather than decades.
The ability to get the worms to respond to electric current solves the problem moving them to the right place at the right time, such as to receive a certain supply of nutrient. Some alternative methods of coaxing such as offering food or shining ultraviolet light on them can take too long to work.
The McMaster researchers, publishing their work in a recent issue of the journal Applied Physics Letters, hope to have the chance to observe up to a thousand worms at a time on a single platform, each moving in its own narrow channel. This will allow a quicker and more detailed look at reactions to a variety of drugs, chemicals, and nanoparticles. This will also help in studying the course of diseases such as obesity and hypertension.
