The field of tissue engineering and regenerative medicine spans from cell-based studies to organoid growth and 3D printing of human tissues. Regenerative medicine research is aimed at improving health and longevity, using tissue chips and a biofabrication facility to address larger challenges with real-world applications. Tissue engineering has many applications but often includes culturing tissues resembling those in the body to model and study human disease, allow higher-accuracy and personalized drug testing, or advance research in organ growth to address the shortage of organs for transplantation.
Tissue engineering and regenerative medicine:
- Stem cell expansion
- Tissue chips
- 3D biofabrication
In microgravity, cells form complex 3D structures—more similar to tissues in the human body—providing a better model for studying cell behavior, advancing regenerative medicine, and testing the effects of new drugs. Additionally, the ability to manufacture soft human tissue, such as blood vessels, has proven to be difficult on Earth. Bioprinting in microgravity could prove beneficial because the scaffolding needed to support printed tissues on Earth is not needed in space to keep printed structures from collapsing.
Spaceflight induces changes in organ systems that result in bone loss, immune dysfunction, cardiovascular deconditioning, and loss of skeletal muscle mass and strength, among other effects. These responses to spaceflight in humans and in model organisms may mimic the onset of health-related outcomes associated with aging and debilitating chronic human diseases on Earth. Spaceflight provides opportunities for the analysis of physical changes in accelerated models of disease and for testing therapeutics to improve wound healing and prevent bone loss, muscle wasting, and other effects of aging and disease.
Why conduct this research in space?
In microgravity, tissues can be formed in three dimensions without supporting architecture, and living matter adapts to the lack of gravity through a variety of mechanisms that we can use to model cellular dysfunction that occurs on Earth.
- Gravity constrains tissue engineering on Earth by flattening and deforming 3D tissue constructs.
- Microgravity allows larger tissues to be constructed and used to inform medicine.
- Growing evidence that interaction of microgravity and living systems elicits responses similar to rapid aging on Earth that can be used for accelerated disease modeling and therapeutic development.
- Combined 3D tissue engineering with accelerated aging effects, informed by the latest biotechnology and artificial intelligence/machine learning offers new and rapidly expanding knowledge, opportunities, and products for disease modeling, testing, and drug development.
Examples of In-Space Production Applications Tissue Engineering and Regenerative Medicine Projects
- Stem Cell Expansion
Stem Cells, which are able to differentiate into other cell types, are critically important in human development as well as tissue repair and regeneration. While stem cells show significant promise for clinical and preclinical applications, there are still numerous challenges related to the field. Some of these challenges include issues associated with stem cell production, maintenance, and differentiation.
The unique environment of the ISS has shown to positively affect these properties in several stem cell projects performed to date. A focused effort in these areas can be expected to lead to the development of a process that alleviates one or more of these current challenges.
- Tissue Chips
Tissue chips are small devices engineered to grow human cells on an artificial scaffold to model the structure and function of human tissues and organs. Because tissue chips are made using human cells and are designed to replicate facets of the physical environment cells experience inside the body, they provide higher-accuracy models.
In microgravity, tissue chips have the potential to accelerate pathways for understanding the mechanisms behind disease and developing new treatments. Spaceflight induces changes in body systems that in many cases mimic the onset of health-related outcomes associated with aging and debilitating chronic human diseases on Earth. Thus, spaceflight provides opportunities both for analysis of these rapid physical changes and for testing of therapeutics in accelerated models of aging or disease.
Organoids are self-organizing 3D tissue cultures assembled from stem cells that can serve as simplified organ systems for accurate and scalable disease modeling and drug testing. They can also be used as tissue patches for regenerative medicine applications.
The integrated biological function in organoids serves as a powerful model for human disease states, and applications of this kind of advanced in-vitro system could enable a wide variety of experiments in microgravity; for example, neurodevelopmental and neurodegenerative disease modeling and applications in personalized medicine.
- 3D Biofabrication
Microgravity enables the production of three-dimensional structures without the need for structural support. Biofabricaiton of tissues in microgravity enables the development of tissues from pluripotent cells with high precision.
Not only to these tissues provide new models to test potential new therapeutics, but they also pave the way for the development of therapies for tissue and artificial organ repair and replacement. Long-term success of biofabrication in microgravity could enable potential medical breakthroughs, including the creation of patient-specific replacement tissues or patches and ultimately help reduce the current shortage of donor organs.