03/29/2007 -- EE Times -- MANHASSET, N.Y. — Massachusetts Institute of Technology researchers have developed a microelectromechanical system (MEMS) that they claim will allow biologists to manipulate the distance between human cells in laboratory experiments. The device works without the aid of microscopes or robotic controls.
Coaxing cells closer together without actually touching them has been among the most frustrating challenges for cell biologists, according to the MIT researchers. Because cells communicate via signals transmitted both through the touching of cell membranes and through soluble molecules that flow between separated cells, biologists need to precisely vary the spacing among cells to study their interactions.
Since some signals induce a cell to change its internal programming, biologists need to rearrange cells over time to learn which signals cause change and which don't.
Previously, researchers had to erect chemical "moats" around cells in an attempt to keep them close but separate. Over time, cells invariably breech the divide. "They are very good at crossing the moat," said Sangeeta Bhatia, associate professor of electrical engineering and computer science at the Harvard-MIT Division of Health Sciences and Technology and Brigham and Women's Hospital.
Bhatia and post-doctoral associate Elliot Hui used the MEMS device to study liver cells. To get liver cells to express specific liver functions, they needed to manipulate supporting stromal cells for 18 hours. The device would allow biologists to keep the stromal, or connective tissue, cells, close together, but would avoid physical contact over the entire 18 hours, which would harm the cells.
Bhatia and Hui reported that the simple device will be useful for exploring a host of cellular interactions when exploring embryonic development and cancer, in which supporting cells are thought to play a role in tumor formation.
The MEMS device and research are described in the March 27 online edition of the Proceedings of the National Academy of Science.
--Nicolas Mokhoff--
