Lab-on-a-chip mimics brain chemistry

Aimed at helping scientists better understand how nerve cells in the brain work together to form the nervous system, a team of engineers from the Whiting School of Engineering and the School of Medicine at at Johns Hopkins University (Baltimore, MD) has developed a micro-scale tool — a lab on a chip — designed to mimic the chemical complexities of the brain. The system hopes to make nerve cell experiments simpler to conduct and control.

The research is based on the principle that nerve cells decide which direction to grow by sensing both the chemical cues flowing through their environment and those attached to the surfaces that surround them. Made of a plastic-like substance and covered with a glass lid, the chip takes advantage of this principle by featuring a system of channels and wells that enable researchers to control the flow of specific chemical cocktails around single nerve cells.

The team put single nerve cells or neurons onto the chip, then introduced specific growth signals in the form of chemicals. They found that the growing neurons turned and grew toward higher concentrations of certain chemical cues attached to the chip’s surfaces, as well as to signaling molecules free-flowing in solution.

Then the neurons were subjected to conflicting signals (both surface bound and cues in solution) where the researchers noticed that the cells turned randomly, suggesting that cells do not choose one signal over the other. This event supports the prevailing theory that one cue can elicit different responses depending on a cell’s surroundings.

The research was funded by the Johns Hopkins Institutes for NanoBiotechnology and Cell Engineering, the National Institutes of Health, March of Dimes, a Klingenstein Fellowship Award, the Alfred P. Sloan Foundation, and the Adelson Medical Research Foundation. For more information, contact Phil Sneiderman at prs@jhu.edu or 443-287-9900 or Mary Spiro at 410-516-4802 or mspiro@jhu.edu.

Christina Nickolas