Extended periods spent in microgravity can take a serious toll on the human body, leading to muscular atrophy, bone density loss, vision problems, and changes to the cardiovascular, endocrine, and nervous systems. At the same time, however, scientists have found that microgravity may play a key role in the future of medicine. This includes bioprinting in space, where cultured cells are printed out to form organic tissues and organs without the need for grafts. Printing in microgravity also ensures that fragile cell structures do not collapse due to pressures caused by Earth’s gravity.
However, space medicine may also have applications for stem cell research, which also benefit from a microgravity environment. Stem cells have countless applications in medicine because of their ability to quickly replicate and differentiate into many different types of cells. Based on experiments carried out aboard the International Space Station (ISS), researchers from the Mayo Clinic in Florida determined that these abilities are enhanced when grown in space. These findings could have significant benefits in the study of disease prevention and treatment on Earth, as well as medical treatments delivered in space.
The research was conducted by Fay Ghani and Abba C. Zubair, two pathologists with the Mayo Clinic’s Center for Regenerative Biotherapeutics and the Department of Laboratory Medicine and Pathology. The paper detailing their experiment and findings was recently published in NPJ Microgravity. For their experiment, the team specifically examined the behavior of several types of adult stem cells, which manage normal wear and tear on the body. These cells are often grown by scientists for the sake of disease research and developing new therapies.
The process is challenging, expensive, and takes a long time. But as Zubair said in a recent interview with ScienceAlert!, the process could be simplified by growing them in space-based labs:
“Studying stem cells in space has uncovered cell mechanisms that would otherwise be undetected or unknown within the presence of normal gravity. That discovery indicates a broader scientific value to this research, including potential clinical applications. The space environment offers an advantage to the growth of stem cells by providing a more natural three-dimensional state for their expansion, which closely resembles growth of cells in the human body.
Ghani and Zubair experimented with many types of adult stem cells and obtained positive results for them all. This included general improvements in cell expansion and stability of replication, which continued after the cell cultures were returned to Earth. In particular, they noted improvements with mesenchymal stem cells (MSCs), a class of multipotent stromal cells that can differentiate into bone, cartilage, muscle, and fat cells – which gives rise to marrow adipose tissue, thus increasing bone density.
When grown in microgravity, these cells were shown to be better at managing immune system responses and reducing inflammation. “That’s in comparison to the two-dimensional culture environment available on Earth that is less likely to imitate human tissue,” said Zubair. “The space research conducted so far is just a starting point. A broader perspective about stem cell applications is possible as research continues to explore the use of space to advance regenerative medicine.”
While there is still a significant amount of research and testing to be done, these results are very promising and indicate that stem cells can be grown faster and in greater numbers in microgravity. Ghani and Zubair are confident that space-grown stem cells will help treat the most common causes of mortality here on Earth, including heart disease, stroke, cancer, and neurodegenerative diseases like dementia, Parkinson’s disease, Multiple Sclerosis (MS), and Amyotrophic Lateral Sclerosis (ALS).
Further Reading: ScienceAlert!, NPJ Microgravity