Establishing Neural Organoid Cultures for Investigating the Effects of Microgravity in Low-Earth Orbit (LEO).

Recent findings from studies involving astronauts and animal models indicate that microgravity increases immune cell activity and potentially alters the white and gray matter of the central nervous system (CNS). To further investigate the impact of microgravity on CNS cells, we established cultures of three-dimensional neural organoids containing isogenic microglia, the brain's resident immune cells, and sent them onboard the International Space Station. When using induced pluripotent stem cell (iPSC) lines from individuals affected by neuroinflammatory and neurodegenerative diseases such as multiple sclerosis (MS) and Parkinson's disease (PD), these cultures can provide novel insights into pathogenic pathways that may be exacerbated by microgravity. We have devised a cryovial culture strategy that enables organoids to be maintained through space travel and onboard the International Space Station (ISS) without the need for medium or carbon dioxide exchange. Here, we provide a comprehensive description of all the steps involved: generating various types of neural organoids, establishing long-term cultures, arranging plans for shipment to the Kennedy Space Center (KSC), and ultimately preparing organoids for launch into low-Earth orbit (LEO) and return to Earth for post-flight analyses.