Biological robots created from a patient’s own cells can move around to heal and regenerate damaged tissue, a study suggests.
Tiny multicellular “Anthrobots” created from epithelial cells in the trachea could be stimulated to move and heal “wounds” created in nerve cells cultured in a laboratory.
Cilia on the cells, which traditionally move mucus, microbes and particles up and out of airways, adapted under particular growth conditions to work like “oars” to propel the cells around.
The findings reveal that changing the cellular environment can create new structures showing unexpected behaviors without genetic modification. The results are published in the journal Advanced Science.
Researcher Michael Levin, a biology professor at Tufts University, pointed out the cellular assemblies constructed in the lab had capabilities beyond what they could do in the body.
“It is fascinating and completely unexpected that normal patient tracheal cells, without modifying their DNA, can move on their own and encourage neuron growth across a region of damage,” he said.
“We’re now looking at how the healing mechanism works, and asking what else these constructs can do.”
The findings follow earlier studies by Levin and team that resulted in the creation of the first, fully functional biobots. These “Xenobots,” created from frog cells, could collaborate to move debris, navigate passageways and copy themselves to a limited extent.
In the current study, the researchers grew a single cell from a human lung in an extracellular matrix for two weeks, before transfer into a minimally viscous environment.
This resulted in a collection of cells that spontaneously organized themselves into small multicellular spheres called organoids.
These spheroid-shaped multicellular biobots ranged in size from 30 to 500 microns, with cilia facing outwards to propel the cells around.
The Anthrobots showed diverse behavior, moving at a range of speeds from 5 to 50 microns per second, with motility patterns ranging from tight loops to straight lines.
When the Anthrobots moved over scratches in a layer of human neurons in a clustered assembly that the researchers dubbed a “superbot,” they were able to encourage new growth and fill in gaps caused by the damage.
The cells lived for 45 to 60 days and were only able to survive under specific conditions, preventing their unintended spread outside the laboratory.
Anthrobots were not able to reproduce and did not have any genetic additions or deletions, further safeguarding their use.
Their ability to be created from a patients’ own cells, without immune responses, and easy re-absorption further promotes their benefits for therapeutic interventions.
“Unlike Xenobots, they don’t require tweezers or scalpels to give them shape, and we can use adult cells—even cells from elderly patients—instead of embryonic cells,” explained researcher Gizem Gumuskaya, a PhD student at Tufts who created the Anthrobots.
“It’s fully scalable—we can produce swarms of these bots in parallel, which is a good start for developing a therapeutic tool.”