Scientists have achieved a groundbreaking feat by creating tiny living robots from human cells, known as anthrobots, which display remarkable mobility and hold promise for potential medical applications. The study, conducted by a team from Tufts University and Harvard University’s Wyss Institute, builds upon previous work in which researchers created the first living robots, or xenobots, using stem cells from African clawed frog embryos.
Study author Michael Levin, Vannevar Bush professor of biology at Tufts’ School of Arts & Sciences, emphasized that the unique properties of xenobots were not solely reliant on their embryonic and amphibian origin. He suggests that this capability is a more general property of living organisms, highlighting the diverse competencies within our own body cells.
The anthrobots, while alive, do not constitute full-fledged organisms as they lack a complete life cycle. Nevertheless, their creation challenges conventional binary categories of what constitutes a robot, an animal, or a machine.
How Were They Created?
The scientists utilized adult human cells sourced from the trachea (windpipe) of anonymous donors with varying ages and sexes. Tracheal cells were chosen due to their accessibility, particularly in the context of research related to Covid-19 and lung diseases. Additionally, these cells possessed unique features that suggested they could exhibit motion.
Tracheal cells are equipped with hairlike projections called cilia that typically assist in clearing tiny particles from air passages in the lungs. Previous studies had also demonstrated the cells’ ability to form organoids, clumps of cells frequently used in research.
The key breakthrough came when Gizem Gumuskaya, a doctoral student at Tufts and study coauthor, manipulated the chemical conditions surrounding the tracheal cells, prompting the cilia to orient outward on the organoids. After several days, the organoids became mobile, with the cilia acting like oars to propel movement.
Gumuskaya explained that while there was no immediate activity on the first few days, around day seven, a rapid transition occurred, resembling the blossoming of a flower. Importantly, each anthrobot developed from a single cell, showcasing a self-assembly process that distinguishes them from previous biological robots, which were manually constructed using molds and seeded cells.
Diverse Shapes and Movement Patterns
The anthrobots created by the research team exhibited diversity in both shape and mobility. Some were spherical and fully covered in cilia, while others resembled football shapes and had irregular cilia coverage. They demonstrated various movement patterns, including straight lines, tight circles, and even some that exhibited wiggling behavior. These anthrobots could survive for up to 60 days under laboratory conditions.
Potential Medical Applications
While the experiments are in the early stages, the ultimate goal is to explore potential medical applications for anthrobots. Researchers examined whether these tiny robots could interact with human neurons grown in a lab dish and mimic damage to assess their healing capabilities.
Surprisingly, the anthrobots were observed to encourage neuron growth towards damaged regions, although the exact mechanisms of this healing process remain unclear.
Falk Tauber, a group leader at the University of Freiburg in Germany, acknowledged the study’s significance, emphasizing the surprising behavior of anthrobots, particularly their ability to bridge and close scratches in human neurons. This achievement suggests diverse applications within laboratories and potentially within the human body.
Importantly, the researchers believe that anthrobots do not pose ethical or safety concerns. They are not derived from human embryos or genetically modified in any way. These robots have a confined environment within the lab and a natural lifespan, eventually biodegrading after a few weeks.