Stem cell mini-hearts grow faster and in greater numbers on the ISS
Updated
Updated · Space.com · May 3
Stem cell mini-hearts grow faster and in greater numbers on the ISS
5 articles · Updated · Space.com · May 3
Cedars-Sinai's Arun Sharma presented the findings in Toronto on 25 April, saying microgravity boosted organoid production versus Earth-based lab systems, though unpublished results gave no figures.
The team says natural weightlessness avoids the agitation used in suspension bioreactors, potentially yielding thicker, more robust heart patches and organoids for drug testing and, eventually, transplant-related therapies.
Sharma has flown heart-cell experiments since 2016 and plans more on NASA's SpaceX CRS-35 mission no earlier than August, but regulatory hurdles mean any clinical use remains years away.
If microgravity unlocks superior heart tissue growth, what other biological manufacturing breakthroughs are now possible beyond Earth?
Beyond lab models, how soon could biomanufacturing in space provide life-saving heart tissue for human transplants?
If space weakens existing hearts, could space-grown heart patches have hidden flaws when brought back to Earth?
Breaking Size Limits: ISS Microgravity Enables 3x Larger, More Complex Heart Organoids for Disease Modeling
Overview
Between 2025 and 2026, Cedars-Sinai researchers successfully grew heart organoids aboard the International Space Station, where microgravity allowed these tissues to grow three times larger and develop more complex structures than on Earth. This environment disrupted normal cell mechanics, activating pathways that boosted cell growth and maturity, including improved calcium handling and vascularization. These advances create powerful new models for studying heart diseases like atrial fibrillation and open doors to personalized medicine. However, challenges remain in safely transporting organoids back to Earth, meeting regulatory standards, and ensuring successful integration after transplantation. Despite these hurdles, space-grown organoids represent a promising leap forward for regenerative medicine and tissue engineering.