MIT scientists have devised a way to study three-dimensional organization of cell clusters, using electricity to move cells into a specific position. The new technique also allows investigators to organize cells into predefined arrangements, and as such, the method might have future applications for bio-tissue engineering.
“We have shown that the behavior of cartilage cells is affected significantly when they are organized in 3-D,” as is the behavior of other types of cells like stem cells, said MIT Associate Professor Sangeeta Bhatia of the Harvard-MIT Division of Health Sciences and Technology (HST), one author of a paper on the technique due to appear in the May issue of Nature Methods.
“This raises questions about how cells might sense their organization in 3-D and how important this might be in other tissues,” said Dirk Albrecht, a postdoctoral associate in Bhatia’s lab and lead author of the paper. “We now have a method to answer some of these questions in the lab.”
Scientists have until now studied cells in 3-D by placing them randomly into a gel. The cells clump together into “cell spheroids,” but that is a slow process, and the size and shape of the cell clumps vary significantly. In addition, cells that communicate by direct contact can end up too far apart.
The new technique allows for precise control of cell organization, and takes minutes to perform compared to hours or days for the other method.
Albrecht and his colleagues have been using a micropatterning technique to carefully position the cells within about 10 microns of each other. That’s nearly the diameter of a cell and about one-fifth the diameter of a human hair. The technique uses a device made with photolithography, the same process used to create circuit patterns on electronic microchips.
In the paper, the MIT researchers said they have formed more than 20,000 cell clusters with precise sizes and shapes within a single gel. They have since scaled that up several-fold. They also have created layers of different cells, attempting to mimic the structure of tissue inside the body.
MIT’s picture caption: Cells are organized differently in normal and diseased cartilage (left). Now these changes can be made and studied in the lab. Here, 3-D cell clusters are precisely re-created in a tissuelike gel (right). The same cells in a conventional 2-D Petri dish look and behave much differently (inset).
The press release…
