Xenobot | |
---|---|
Industry | Robotics, Synthetic biology |
Application | Medicine, environmental remediation |
Dimensions | Microscale |
Fuel source | Nutrients |
Self-propelled | Yes |
Components | Frog cells |
Inventor | Sam Kriegman, Douglas Blackiston, Michael Levin, Josh Bongard |
Invented | 2020 |
Xenobots, named after the African clawed frog ( Xenopus laevis ), [1] are synthetic lifeforms that are designed by computers to perform some desired function and built by combining together different biological tissues. [1] [2] [3] [4] [5] [6] There is debate among scientists whether xenobots are robots, organisms, or something else entirely.
The first xenobots were built by Douglas Blackiston according to blueprints generated by an AI program, which was developed by Sam Kriegman. [3]
Xenobots built to date have been less than 1 millimeter (0.04 inches) wide and composed of just two things: skin cells and heart muscle cells, both of which are derived from stem cells harvested from early (blastula stage) frog embryos. [7] The skin cells provide rigid support and the heart cells act as small motors, contracting and expanding in volume to propel the xenobot forward. The shape of a xenobot's body, and its distribution of skin and heart cells, are automatically designed in simulation to perform a specific task, using a process of trial and error (an evolutionary algorithm). Xenobots have been designed to walk, swim, push pellets, carry payloads, and work together in a swarm to aggregate debris scattered along the surface of their dish into neat piles. They can survive for weeks without food and heal themselves after lacerations. [2]
Other kinds of motors and sensors have been incorporated into xenobots. Instead of heart muscle, xenobots can grow patches of cilia and use them as small oars for swimming. [8] However, cilia-driven xenobot locomotion is currently less controllable than cardiac-driven xenobot locomotion. [9] An RNA molecule can also be introduced to xenobots to give them molecular memory: if exposed to specific kind of light during behavior, they will glow a prespecified color when viewed under a fluorescence microscope. [9]
Xenobots can also self-replicate. Xenobots can gather loose cells in their environment, forming them into new xenobots with the same capability. [10] [11] [12]
Currently, xenobots are primarily used as a scientific tool to understand how cells cooperate to build complex bodies during morphogenesis. [1] However, the behavior and biocompatibility of current xenobots suggest several potential applications to which they may be put in the future.
Xenobots are composed solely of frog cells, making them biodegradable and environmentally friendly robots. Unlike traditional technologies, xenobots do not generate pollution or require external energy inputs during their life-cycle. They move using energy from fat and protein naturally stored in their tissue, which lasts about a week, at which point they simply turn into dead skin cells. [2] Additionally, since swarms of xenobots tend to work together to push microscopic pellets in their dish into central piles, [2] it has been speculated that future xenobots might be able to find and aggregate tiny bits of ocean-polluting microplastics into a large ball of plastic that a traditional boat or drone could gather and bring to a recycling center.
In future clinical applications, such as targeted drug delivery, xenobots could be made from a human patient’s own cells, which would virtually eliminate the immune response challenges inherent in other kinds of micro-robotic delivery systems. Such xenobots could potentially be used to scrape plaque from arteries, and with additional cell types and bioengineering, locate and treat disease.
Anatomy is the branch of morphology concerned with the study of the internal structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having its beginnings in prehistoric times. Anatomy is inherently tied to developmental biology, embryology, comparative anatomy, evolutionary biology, and phylogeny, as these are the processes by which anatomy is generated, both over immediate and long-term timescales. Anatomy and physiology, which study the structure and function of organisms and their parts respectively, make a natural pair of related disciplines, and are often studied together. Human anatomy is one of the essential basic sciences that are applied in medicine, and is often studied alongside physiology.
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation.
In biology, tissue is an assembly of similar cells and their extracellular matrix from the same embryonic origin that together carry out a specific function. Tissues occupy a biological organizational level between cells and a complete organ. Accordingly, organs are formed by the functional grouping together of multiple tissues.
Microbotics is the field of miniature robotics, in particular mobile robots with characteristic dimensions less than 1 mm. The term can also be used for robots capable of handling micrometer size components.
Cryobiology is the branch of biology that studies the effects of low temperatures on living things within Earth's cryosphere or in science. The word cryobiology is derived from the Greek words κρῧος [kryos], "cold", βίος [bios], "life", and λόγος [logos], "word". In practice, cryobiology is the study of biological material or systems at temperatures below normal. Materials or systems studied may include proteins, cells, tissues, organs, or whole organisms. Temperatures may range from moderately hypothermic conditions to cryogenic temperatures.
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Tissue engineering is a biomedical engineering discipline that uses a combination of cells, engineering, materials methods, and suitable biochemical and physicochemical factors to restore, maintain, improve, or replace different types of biological tissues. Tissue engineering often involves the use of cells placed on tissue scaffolds in the formation of new viable tissue for a medical purpose, but is not limited to applications involving cells and tissue scaffolds. While it was once categorized as a sub-field of biomaterials, having grown in scope and importance, it can is considered as a field of its own.
Striated muscle tissue is a muscle tissue that features repeating functional units called sarcomeres. The presence of sarcomeres manifests as a series of bands visible along the muscle fibers, which is responsible for the striated appearance observed in microscopic images of this tissue. There are two types of striated muscle:
Regeneration in biology is the process of renewal, restoration, and tissue growth that makes genomes, cells, organisms, and ecosystems resilient to natural fluctuations or events that cause disturbance or damage. Every species is capable of regeneration, from bacteria to humans. Regeneration can either be complete where the new tissue is the same as the lost tissue, or incomplete after which the necrotic tissue becomes fibrotic.
A wetware computer is an organic computer composed of organic material "wetware" such as "living" neurons. Wetware computers composed of neurons are different than conventional computers because they use biological materials, and offer the possibility of substantially more energy-efficient computing. While a wetware computer is still largely conceptual, there has been limited success with construction and prototyping, which has acted as a proof of the concept's realistic application to computing in the future. The most notable prototypes have stemmed from the research completed by biological engineer William Ditto during his time at the Georgia Institute of Technology. His work constructing a simple neurocomputer capable of basic addition from leech neurons in 1999 was a significant discovery for the concept. This research was a primary example driving interest in creating these artificially constructed, but still organic brains.
Josh Bongard is a professor at the University of Vermont and a 2010 PECASE awardee.
Artificial reproduction is the re-creation of life by other than the natural means and natural causes. It involves building of new life following human plans and projects. Examples include, artificial selection, artificial insemination, in vitro fertilization, artificial womb, artificial cloning, and kinematic replication.
Physalaemin is a tachykinin peptide obtained from the Physalaemus frog, closely related to substance P. Its structure was first elucidated in 1964.
A myofibroblast is a cell phenotype that was first described as being in a state between a fibroblast and a smooth muscle cell.
Muscle is a soft tissue, one of the four basic types of animal tissue. Muscle tissue gives skeletal muscles the ability to contract. Muscle is formed during embryonic development, in a process known as myogenesis. Muscle tissue contains special contractile proteins called actin and myosin which interact to cause movement. Among many other muscle proteins, present are two regulatory proteins, troponin and tropomyosin.
The Langendorff heart or isolated perfused heart assay is an ex vivo technique used in pharmacological and physiological research using animals and also humans. Named after the German physiologist Oskar Langendorff, this technique allows the examination of cardiac contractile strength and heart rate without the complications of an intact animal or human. After more than 100 years, this method is still being used.
In vitro muscle testing is a method used to characterize properties of living muscle tissue after removing it from an organism, which allows more extensive and precise quantification of its properties than in vivo testing. In vitro muscle testing has provided the bulk of scientific knowledge of muscle structure and physiology, and how both relate to organismal performance. Stem cell research relies on in vitro muscle testing to establish sole muscle cell function and its individual behavior apart from muscle cells in the presence of nonmuscle cells seen in in vitro studies.
Soft robotics is a subfield of robotics that concerns the design, control, and fabrication of robots composed of compliant materials, instead of rigid links. In contrast to rigid-bodied robots built from metals, ceramics and hard plastics, the compliance of soft robots can improve their safety when working in close contact with humans.
Michael Levin is an American developmental and synthetic biologist at Tufts University, where he is the Vannevar Bush Distinguished Professor. Levin is a director of the Allen Discovery Center at Tufts University and Tufts Center for Regenerative and Developmental Biology. He is also co-director of the Institute for Computationally Designed Organisms with Josh Bongard.
The Wyss Institute for Biologically Inspired Engineering is a cross-disciplinary research institute at Harvard University focused on bridging the gap between academia and industry by drawing inspiration from nature's design principles to solve challenges in health care and the environment. It is focused on the field of biologically inspired engineering to be distinct from bioengineering and biomedical engineering. The institute also has a focus on applications, intellectual property generation, and commercialization.