Humankind has long sought the cures to diseases—from cancers to osteoporosis—on Earth. Even as the rainforests continue to reveal natural medicinal compounds and biochemical labs synthesize complex pharmaceuticals, each advancement only brings forth millions of unanswered questions concerning the human body and its health. Yet, what if humankind has been looking in the wrong place for these answers? What if the solutions to disease aren’t found on Earth at all but rather in the stars?
In August 2021, the Space Hub of the University of Zurich, in partnership with Airbus Defence and Space, prepared to traverse this ambiguous territory and continue the expansion of medicine into this new frontier. Their project, called “3D Organoids in Space,” seeks to develop a process of constructing “3-D organ-like tissues” in microgravity conditions. In order to achieve this lofty goal, this experiment aims to understand the interaction between the minimal presence of gravity and the differentiation of stem cells that leads to tissue development. In March 2020, a successful preliminary test was completed in which human stem cells were grown in 250 test tubes on the International Space Station (ISS) and compared to respective controls on Earth. Ultimately, this experiment reveals the great potential for stem cell differentiation in microgravity conditions as after just 4 months of growth, these differentiated liver, blood, and cartilage structures observed on the ISS were astonishingly advanced in comparison to the Earth control group .
In order to understand exactly how scientists were able to generate actual human tissue at such an impressive rate requires an examination of gravity. On Earth, conducting experiments tracking stem cell differentiation has two main drawbacks as a result of gravitational force. First, scientists must employ a supporting skeleton to guide cell growth and avoid the deformation of tissue structures. Furthermore, scientists must be prepared for a significantly reduced rate of stem cell differentiation. With its zero-gravity conditions, space presents an ideal location to avoid both of these setbacks in the industrial production of tissues. Ultimately, this change of environment could facilitate the speed at which organ-like structures are produced and utilized in rectifying the insufficient supply of organ donors. Moreover, this constructed tissue could be employed as a substitute for animal testing utilized by pharmaceutical companies in determining the toxicity of their potential products. Not only would this limit animal casualties resulting from these experiments, but employing human tissue would also provide a more accurate approximation of the effects potential pharmaceuticals can have on the human body.
An accelerated procedure for tissue production is far from the only medical discovery illuminated by space. Microgravity has been essential to examining the properties of cells, organoids, and protein clusters, and astronauts on board the ISS have also played a crucial role in these experiments. In particular, the Myotones project has collected data concerning the changes in the “tone, elasticity, and rigidity” of the astronauts’ muscles . The results have subsequently been used to determine treatments for muscle and bone atrophy, including the development of exercise regimes. ISS astronauts have also participated in studies tracking bone density loss, given the accelerated development and progression of related health conditions observed in space .
The ISS is also home to advanced disease studies on Alzheimer’s disease, Parkinson’s disease, cancers, and asthma. For example, researchers have been able to identify and examine protein clusters related to dementia in microgravity conditions. In addition, the Angiex Project has developed endothelial cells (which control the blood supply to cancerous tumors) with greater longevity on the ISS . As a result, these cells can provide a basis for testing future cancer therapeutics in a more efficient, cost-effective manner.
Overall, even as the study of medicine moves farther from this planet, the effects of its research are benefiting humankind to that much greater of an extent. By continuing to follow Stephen Hawking’s advice to “look up at the stars and not down at [our] feet,”  the next generation of scientists, engineers, physicians, and entrepreneurs will truly be able to transform the field of medicine, and most importantly, the lives of patients and their families depending on its success.