Tiny robots made from human cells repair damaged tissue
Scientists have developed tiny robots made from human cells capable of repairing damaged nerve tissue1. The ‘robots’ were made using human trachea cells and could be used in personalized medicine in the future.
Developmental biologist Michael Levine at Tufts University in Medford, Massachusetts, and his colleagues had previously developed tiny robots that used clumps of embryonic frog cells. But the medical applications of these xenobots were limited, because they were not derived from human cells and because they had to be hand-sculpted into the desired shape. Researchers have now developed self-assembling robots and are studying their therapeutic potential using human tissue grown in the laboratory. They published their findings in Advanced science.
Levine and his team cultured spheroids of human tracheal skin cells in a gel for two weeks, before removing the clusters and culturing them for a week in a less viscous solution. This caused tiny hairs on the cells called cilia to move outward from the spheroids instead of inward. These cilia served as paddles, and the researchers found that the resulting robots — each containing a few hundred cells — often swam in one of several patterns. Some swam in straight lines, others swam in circles or arcs, and others moved chaotically.
To test the therapeutic potential of humanoid robots, Levin and his colleagues placed several of them in a small dish. There, the robots fused together to form a “superrobot,” which the researchers placed on a layer of scratched neural tissue. Within three days, the nerve cell sheet had completely healed under the giant robot. This was surprising, says study co-author Gizem Gomosskaya, also a developmental biologist at Tufts University, because the robot’s cells were able to perform this repair function without needing any genetic modification. “It’s not clear that you’re going to get that kind of response,” she says.
Going forward, Levin, Gomoskaya and their colleagues believe that robots made from a person’s own tissue could be used to clean arteries, break up mucus, or deliver drugs, with or without genetic engineering. By combining several types of cells and exploring other stimuli, it may also be possible to develop biobots — robots made of biological materials — that can perform complex functions, such as building or exploring tissues.
“Once we understand what cell populations are predisposed to and what they are capable of doing, we can start to get a handle on that, not just for autonomous robotics, but also for regenerative medicine,” including limb regrowth, Levin says.