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Scientist Use AI To Assemble Frog Cells into a 'Programmable Organism'

• By John K. Waters
• 01/23/2020

A team of biologists and roboticists has created what is being described as "an entirely new life form" by assembling living cells scraped from African frog embryos into millimeter-wide "xenobots."

These biological machines have the ability to move toward a target, pick up, say, medicine that needs to be carried to a specific location within a live patient, and heal themselves after being cut, they said.

The scientists revealed the results of their efforts in a paper ("A Scalable Pipeline for Designing Reconfigurable Organisms"), available now on the Proceedings of the National Academy of Sciences Web page. Their research was sponsored by the Defense Advanced Research Projects Agency (DARPA).

"These are novel machines," study co-leader Joshua Bongard, a computer scientist and robotics expert at the University of Vermont, said in a statement. "They're neither a traditional robot nor a known species of animal. It's a new class of artifact: a living, programmable organism."

The team used the Deep Green supercomputer cluster at the university's Vermont Advanced Computing Core (VACC) to create a scalable "pipeline" for designing these novel machines in silico (computer models), evolving them with an algorithm, programming them to perform specific functions, and then using those designs to make cell-based living systems with predicted behaviors.

"The approach is organized as a linear pipeline that takes as input a description of the biological building blocks to be used and the desired behavior the manufactured system should exhibit," the scientists wrote. "The pipeline continuously outputs performant living systems that embody that behavior in different ways. The resulting living systems are novel aggregates of cells that yield novel functions: above the cellular level, they bear little resemblance to existing organs or organisms."

They designed these novel machines at UVM and then assembled and tested them at Tufts University.

"We can imagine many useful applications of these living robots that other machines can't do, like searching out nasty compounds or radioactive contamination, gathering microplastic in the oceans, traveling in arteries to scrape out plaque," said study co-leader Michael Levin, who directs the Center for Regenerative and Developmental Biology at Tufts, in a statement.

Also on the team were doctoral student Sam Kriegman and microsurgeon Douglas Blackiston, who worked with Levin to harvest and assemble the microscopic stem cells of the Xenopus laevis, from which the moniker "xenobots" comes.

The ability to create "reconfigurable organisms" has enormous potential, the scientists argued in their report, for everything from health care to combating the effects of climate change. And they're certainly not the only ones working in this area. What these researchers may have done, however, is to provide the scalability piece, with a process that employs an evolutionary algorithm that can be reconfigured to design drugs, autonomous machines, metamaterials or architecture.