Overview

• NASA-funded researchers flew hematopoietic stem and progenitor cells from individual donors on four SpaceX ISS missions lasting 30 to 45 days, with matched Earth controls.
• Space-exposed cells showed reduced self-renewal, greater vulnerability to DNA damage, telomere aging signals, mitochondrial inflammation, and activation of normally silent genomic regions.
• Many alterations partially reversed after the cells returned to a young or Earth-like environment, indicating potential for mitigation strategies.
• Responses differed by donor, suggesting variable resilience that the team says is supported by follow-up work now awaiting publication.
• UC San Diego partnered with Space Tango on the nanobioreactors, and the findings are published in Cell Stem Cell with additional countermeasure studies underway on a mission launched last month.