CASIS, NCATS, and NASA need your ideas to design a mission patch for an exciting new research program on the International Space Station! Tissue Chips in Space (“Chips in Space” for short) is a four-year partnership between the Center for the Advancement of Science in Space (CASIS) and the National Center for Advancing Translational Sciences (NCATS), part of the National Institutes of Health (NIH). Researchers are designing experiments that will study tissue chips in the microgravity environment of the International Space Station. This space-based research will benefit people’s lives here on Earth by working toward a better understanding of human diseases and better methods for testing therapies.
Timeline of events:
- August 9 – September 8: Submit your design (or designs — you can enter more than once!)
- September 9 – 16: Vote for your favorite designs in the Gallery
- September 18: “Crowd Favorites” for each age group will be announced
To design a meaningful patch, you’ll need to know about the mission. Here’s an introduction:
What are tissue chips, and what are they doing in space?
An exciting and promising new area of medical research is the use of miniaturized models of human systems called tissue chips or organs-on-chips. These devices are built using some of the same techniques used to make microchips for computers. Because they use real human cells, tissue chips are ideal for testing the effects of medicines and other treatments on human systems.
You can’t shrink a whole organ down to the size of a chip, but you can engineer a model that imitates an essential function of the organ. Researchers identify the types of cells involved in an organ’s function and study how those cells are organized. They find the smallest, simplest way to re-create the function.
A typical tissue chip is a small block of clear plastic containing tiny spaces and structures lined with living human cells. The plastic may be flexible to allow the tissues to expand and contract (as in a breathing lung or beating heart). Tubes can be attached to send liquids or gases flowing through narrow channels in the chip.
Each chip simulates one type of tissue such as lung, brain, bone, or kidney tissue. An example is this small airway-on-a-chip developed at the Wyss Institute for Biologically Inspired Engineering at Harvard University. It can be used to test medicines to treat inflammatory conditions such as asthma.
- Lab-grown mini-organs help model disease, test new drugs – Article in Science Magazine
- Human Organs-on-Chips – Video by the Wyss Institute at Harvard University
Tissue chips can reduce animal testing
The earliest stage of testing a drug or vaccine uses small samples of cells in plastic or glass containers. Known as in vitro (“within the glass”) testing, this method can reveal a drug’s direct effects on specific types of cells, but it can’t show how the drug affects a whole organ or a system of organs. To study a drug’s system-wide effects on the body, researchers use in vivo (“within the living”) testing. Before testing the drug in people, researchers typically test it in animal models such as mice, rats, rabbits, and pigs.
Animal testing is far from perfect. Even though researchers are careful to treat research animals humanely and use them only when necessary, many people are uncomfortable with animal testing. And animals are only approximate models; a disease or drug may have different effects in animals than in humans.
Tissue chips could provide a human-accurate, animal-friendly, low-risk way to test a drug’s system-wide effects. Ongoing research is improving tissue chips’ ability to mimic complex organ functions. Linking several tissue chips together can simulate interconnected systems in the body. Eventually, in vitro testing with networks of tissue chips could be more useful than in vivo testing with animal models!
Tissue chips can customize medical treatments
Tissue chips have exciting potential in the field of personalized medicine. Treatments for hereditary disorders, cancers, and other non-infectious diseases are not equally effective for everyone. In one patient, a drug might help the disease symptoms successfully without unpleasant side effects. But in another patient, that same drug might help less and have more severe side effects!
It’s hard to predict exactly how a drug will affect you before you take it. But what if your doctor could start by testing the drug on an accurate model of you? Years from now, a network of tissue chips custom-built with your own cells could act as a “mini-me” for testing therapies to find the best one.
Explore “Chip” to learn more about how modeling a human body with a system of tissue chips.
Why send tissue chips to space?
Researchers are excited to study tissue chips in microgravity, the weightless environment on the International Space Station. On Earth, gravity forces cells to grow in flat layers along the bottom of a container. But in microgravity, cells can grow in 3-D, forming structures that better imitate human organs.
Microgravity influences many other details of cell behavior. Some sections of the cells’ DNA are copied and used more frequently while other DNA sections are used less, leading to changes in the production rates of certain chemicals. This affects how the cells grow, specialize, communicate, and age. Microgravity also affects the mobility of cells that move on their own, such as white blood cells.
Chips In Space Experiments In the Works
Astronauts' immune systems don’t work as well in microgravity as on Earth. Why? Is the whole body’s immunity affected, or is the problem limited to certain organs? A biological engineer at University of Pennsylvania and a physician-scientist at the Children’s Hospital of Philadelphia are exploring these questions in collaboration with Space Technology and Advanced Research Systems (STaARS) and SpacePharma. They will use two types of tissue chips:
(1) An airway-on-a-chip serves as a model of infection in a specific organ: the lung.
(2) A bone-marrow-on-a-chip model represents whole-body infection, because bone marrow produces white blood cells that circulate throughout the body.
One set of tissue chips will be tested on Earth and an identical set will fly to the ISS. Comparing the two sets will show whether tissue chips in microgravity mimic human tissues better than those on Earth.
For a more technical description, see Lung Host Defense in Microgravity.
Researchers at the Boston-based biotech company Emulate, in collaboration with Space Tango, are developing a new mini-lab for the Space Station that can be used repeatedly for a wide range of tissue chip experiments. Refining the hardware on the ISS will also lead to better lab equipment on Earth. In this mini-lab they will test a tissue chip that mimics the blood-brain barrier, which protects brain health by keeping out infections and unwanted chemicals. Some chips will model healthy tissue and others will model effects of impact injuries, neurological diseases, and cancers. Parallel experiments on the ISS and on Earth will show how microgravity affects cells in the blood-brain barrier.
For a more technical description, see Organs-on-Chips as a Platform for Studying Effects of Microgravity on Human Physiology: Blood-Brain Barrier Chip in Health and Disease.
It’s no fun to have injuries or arthritis in your joints! Medical researchers want to develop better treatments for healing joint damage and degradation. Joints such as the wrist, elbow, hip, and knee involve a complex interaction of bone, cartilage, and fluid encased in a membrane called the synovium. Researchers in the Department of Biological Engineering at MIT have developed a tissue chip that mimics the cartilage-bone-synovium system. The researchers are working with Techshot on an experiment to study medicines that could treat the persistent problems that can plague joints after injuries.
For a more technical description, see Cartilage-Bone-Synovium Microphysiological System: Musculoskeletal Disease Biology in Space.
Cells age at a slightly accelerated rate in microgravity. This has been shown in many experiments including NASA’s Twins Study, in which Scott Kelly lived on the ISS for a year while his identical twin brother Mark stayed on Earth. After the astronauts return home, how long does it take their cells to resume aging at a normal rate? Physician-scientists at UCSF School of Medicine who specialize in organ transplants are partnering with Space Technology and Advanced Research Systems (STaARS) to study cell aging with tissue chips containing stem cells. They will examine not only the effect of microgravity, but also the effect of returning to Earth gravity.
For a more technical description, see Microgravity as Model for Immunological Senescence and its Impact on Tissue Stem Cells and Regeneration.
A kidney-on-a-chip is the focus of this experiment developed by researchers at the Kidney Research Institute of the University of Washington, Seattle, in partnership with BioServe Space Technologies. They will compare kidney tissue chips on the ISS and on Earth to learn how microgravity affects kidney function. This research will help improve the prevention and treatment of kidney stones both in astronauts and in patients here on Earth.
For a more technical description, see Effects of Microgravity on the Structure and Function of Proximal and Distal Tubule Microphysiological System.