A book is made of wood. But it is not a tree. The dead cells have been repurposed to serve another need.
Now a team of scientists has repurposed living cells—scraped from frog embryos—and assembled them into entirely new life-forms. These millimeter-wide “xenobots” can move toward a target, perhaps pick up a payload (like a medicine that needs to be carried to a specific place inside a patient)—and heal themselves after being cut.
“These are novel living machines,” says Joshua Bongard, a computer scientist and robotics expert at the University of Vermont who co-led the new research. “They’re neither a traditional robot nor a known species of animal. It’s a new class of artifact: a living, programmable organism.”
The new creatures were designed on a supercomputer at UVM—and then assembled and tested by biologists at Tufts University. “We can imagine many useful applications of these living robots that other machines can’t do,” says co-leader Michael Levin who directs the Center for Regenerative and Developmental Biology at Tufts, “like searching out nasty compounds or radioactive contamination, gathering microplastic in the oceans, traveling in arteries to scrape out plaque.”
The results of the new research were published January 13 in the Proceedings of the National Academy of Sciences.
Bespoke living systems
People have been manipulating organisms for human benefit since at least the dawn of agriculture, genetic editing is becoming widespread, and a few artificial organisms have been manually assembled in the past few years—copying the body forms of known animals.
But this research, for the first time ever, “designs completely biological machines from the ground up,” the team writes in their new study.
With months of processing time on the Deep Green supercomputer cluster at UVM’s Vermont Advanced Computing Core, the team—including lead author and doctoral student Sam Kriegman—used an evolutionary algorithm to create thousands of candidate designs for the new life-forms. Attempting to achieve a task assigned by the scientists—like locomotion in one direction—the computer would, over and over, reassemble a few hundred simulated cells into myriad forms and body shapes. As the programs ran—driven by basic rules about the biophysics of what single frog skin and cardiac cells can do—the more successful simulated organisms were kept and refined, while failed designs were tossed out. After a hundred independent runs of the algorithm, the most promising designs were selected for testing.
Then the team at Tufts, led by Levin and with key work by microsurgeon Douglas Blackiston—transferred the in silico designs into life. First they gathered stem cells, harvested from the embryos of African frogs, the species Xenopus laevis. (Hence the name “xenobots.”) These were separated into single cells and left to incubate. Then, using tiny forceps and an even tinier electrode, the cells were cut and joined under a microscope into a close approximation of the designs specified by the computer.
Assembled into body forms never seen in nature, the cells began to work together. The skin cells formed a more passive architecture, while the once-random contractions of heart muscle cells were put to work creating ordered forward motion as guided by the computer’s design, and aided by spontaneous self-organizing patterns—allowing the robots to move on their own.
These reconfigurable organisms were shown to be able move in a coherent fashion—and explore their watery environment for days or weeks, powered by embryonic energy stores. Turned over, however, they failed, like beetles flipped on their backs.
Later tests showed that groups of xenobots would move around in circles, pushing pellets into a central location—spontaneously and collectively. Others were built with a hole through the center to reduce drag. In simulated versions of these, the scientists were able to repurpose this hole as a pouch to successfully carry an object. “It’s a step toward using computer-designed organisms for intelligent drug delivery,” says Bongard, a professor in UVM’s Department of Computer Science and Complex Systems Center.
Image Credit: Youtube

News This Week
Scientists Use Exotic DNA To Help Create “Climate-Proof” Crops
The incorporation of exotic DNA from wild relatives into wheat results in a remarkable yield increase of up to 50%, even in hot weather, surpassing elite lines without these genes. Amid a year of [...]
Australia becomes first country to recognise psychedelics as medicines
Australia has become the first country to recognise psychedelics as medicines, after the Therapeutic Goods Administration took researchers by surprise and approved the psychedelic substances in magic mushrooms and MDMA for use by people [...]
Silver nanoparticles show promise in fighting antibiotic-resistant bacteria
In a new study, scientists with the University of Florida have found that a combination of silver nanoparticles and antibiotics is effective against antibiotic-resistant bacteria. The researchers hope to turn this discovery into viable [...]
Combating severe cancer with a new drug delivery system
Peritoneal cancer is difficult to treat and has a poor survival prognosis. But a new and effective nanomedicine delivery system is offering some hope. The company is called NaDeNo and is well underway with [...]
New Research Shows How Ketamine Acts As “Switch” in the Brain
According to a new study by researchers at Penn Medicine, ketamine, which is well-known as an anesthetic and is becoming increasingly popular as an antidepressant, dramatically reorganizes activity in the brain, almost as if [...]
Supercharged T Cells: A New Way To Kill Pancreatic Cancer With Minimal Side Effects
A new immunotherapy releases cancer-killing cytokines only within the tumor. Researchers at the University of California San Francisco (UCSF) have developed a new T cell-based immunotherapy that selectively targets cancer cells, producing a powerful anti-cancer cytokine [...]
AI has designed bacteria-killing proteins from scratch – and they work
An AI was tasked with creating proteins with anti-microbial properties. Researchers then created a subset of the proteins and found some did the job. An AI has designed anti-microbial proteins that were then tested [...]
Using nanoparticles, researchers can identify and deliver synergistic combinations of cancer drugs
Treating cancer with combinations of drugs can be more effective than using a single drug. However, figuring out the optimal combination of drugs, and making sure that all of the drugs reach the right [...]
Humanity May Reach Singularity Within Just 7 Years, Trend Shows
By one unique metric, we could approach technological singularity by the end of this decade, if not sooner. A translation company developed a metric, Time to Edit (TTE), to calculate the time it takes for professional [...]
HYPER (Highly Interactive Particle Relics) – A New Model for Dark Matter
Phase transition in early universe changes strength of interaction between dark and normal matter. Dark matter remains one of the greatest mysteries of modern physics. It is clear that it must exist, because without [...]
New Nanoparticles Deliver Therapy Brain-Wide and Edit Alzheimer’s Gene
Summary: Researchers have developed a new family of nano-scale capsules capable of carrying CRISPR gene editing tools to different organs of the body before harmlessly dissolving. The capsules were able to enter the brains of [...]
Cancer’s Secret Weapon? Enzyme That Protects Against Viruses May Fuel Tumor Evolution
An enzyme that defends human cells against viruses can help drive cancer evolution towards greater malignancy by causing myriad mutations in cancer cells, according to a study led by investigators at Weill Cornell Medicine. The [...]
Scientists Uncover Japanese Fruit Juice That May Help Prevent Lung Cancer
Using a mouse model, Japanese researchers unleash the likely mechanism of action of Actinidia arguta (sarunashi) juice on lung cancer development. Lung cancer is a leading cause of death in Japan and across the [...]
In-place manufacturing method improves gas sensor capabilities, production time
When used as wearable medical devices, stretchy, flexible gas sensors can identify health conditions or issues by detecting oxygen or carbon dioxide levels in the breath or sweat. They also are useful for monitoring [...]
In the core of the cell: New insights into the utilization of nanotechnology-based drugs
Novel drugs, such as vaccines against covid-19, among others, are based on drug transport using nanoparticles. Whether this drug transport is negatively influenced by an accumulation of blood proteins on the nanoparticle’s surface was [...]
The costly lesson from COVID: why elimination should be the default global strategy for future pandemics
Imagine it is 2030. Doctors in a regional hospital in country X note an expanding cluster of individuals with severe respiratory disease. Rapid whole-genome sequencing identifies the disease-causing agent as a novel coronavirus. Epidemiological [...]