In mid-January 2020, the world was amazed to learn of the creation by American scientists of this quadrupedal organism with a diameter of 650 to 750 microns, a little smaller than a pinhead, capable of moving and of regenerate after being cut.
The creature was named xenobot after the African frog Xenopus laevis from which are derived the embryonic stem cells that compose it.
The xenobot was designed in part using the supercomputer Deep green from the University of Vermont. It was then assembled and tested by biologists at Tufts University.
Researcher Joshua Bongard and his colleagues now explain that their creation can, by swimming in a Petri dish, find single cells, collect them by the hundreds and assemble them with their
mouth in the shape of Pac-Man to create
In just a few days, these
babies take on the appearance of a xenobot
adult and start to move like them.
In turn, these new xenobots can find cells and create copies of themselves. Again and againJoshua Bongard notes in a statement released by the University of Vermont.
From the frog to the xenobot
In the frog Xenopus laevis, the embryonic cells used in this work would turn into skin.
They would be on the outside of the tadpole, preventing pathogens from enteringsays Michael Levin, professor of biology at Tufts University and co-author of the new research.
But we put them in a new context to give them a chance to reimagine their multicellular.
And what they imagine is very different from the skin.
This is something that has never been observed beforesays his colleague Douglas Blackiston, also a researcher at Tufts University.
These cells have the genome of a frog, but freed from the obligation to transform into tadpoles, they use their collective intelligence […] to do something amazing.
Thus, if previous experiments had made it possible to establish that xenobots could accomplish simple tasks, the present work goes even further. They show that these biological objects – which are no more and no less than computer-designed cells – replicate spontaneously.
There was no clue that these cells could work together on this new task, which is to bring together and then compress separate cells into functional self-production., wonders Michael Levin.
These are frog cells that replicate in a very different way than frog cells. No animal or plant known to science replicates itself in this way., adds Sam Kriegman, the main author of this work, the details of which are published in Proceedings of the National Academy of Sciences (New window) (in English).
When alone, a xenobot consists of 3000 cells and forms a sphere.
These cells can have “babies”, but it is very difficult to keep the system reproducing from generation to generation., explains Mr. Kriegman.
However, thanks to artificial intelligence and the supercomputer Deep green, an evolutionary algorithm has been able to test billions of body shapes to find those that allow cells to be more efficient in so-called replication
cinematic, based on movement.
Deep green to figure out how to adjust the shape of the parents. After months of work, the AI came up with some weird models, including one that looks like Pac-Man, “” text “:” So we asked Deep Green to figure out how to adjust the parents’ shape. After months of work, the AI came up with some weird models, including one that looks like Pac-Man “}}”>So we asked Deep green to figure out how to adjust the shape of the parents. After months of work, the AI came up with some weird models, including one that looks like Pac-Man, says Mr. Kriegman.
It is not something that a human engineer would have imagined. Why only one small mouth? Why not five? asks Sam Kriegman.
The researchers still created and then tested xenobots
parents in the shape of Pac-Man.
These parents built children, who built grandchildren, who built great-grandchildren, who built great-great-grandchildren. In other words, the right design has significantly extended the number of generations., rejoices Sam Kriegman.
If kinematic replication is well known at the level of molecules, it had never before been observed at the level of cells or of whole organisms.
We have discovered that there is a previously unknown space within living systems, and that it is a very large space., notes Joshua Bongard.
We had found xenobots swimming. And now in this study we have found xenobots that are replicating kinematically. What else is there to learn?
This work promises to revolutionize medicine, according to the researchers.
If we knew how to tell groups of cells what we want them to achieve, it would be possible to cure traumatic injuries, birth defects, cancer and even aging., notes Michael Levin.
All of these health problems exist because we don’t know how to predict and control which groups of cells are going to build. Xenobots are a new platform to teach us, concludes Mr. Levin.
In addition, these robots will be able to deliver drugs to places, help decontaminate radioactive areas and collect microplastics in the oceans.
Towards ethical drifts?
The construction of these xenobots is, according to the researchers, a small step towards deciphering what they call the morphogenetic code, which provides a complete view of the organization of organisms, but also of how they handle information. according to their history and their environment.
The creation of xenobots – and the breakthroughs that will come in the coming years – will very likely lead to rapid technological changes and even more advanced and complex biological manipulations, from which ethical drifts could result.
This fear is not unreasonable, since playing in complex systems that one does not understand can have unintended consequences., recalled Michael Levin when announcing the creation of xenobots.