TorPause: Efficient Static Organ Preservation for Transplants

Bhadury, J.; Tajima, T.; Suchy, F. P.; Masaki, H.; Zhang, J.; Rivera, M.; Nishimura, T.; Charlesworth, C. T.; Esquivel, C. O.; Nakauchi, H.

doi:10.64898/2026.10.08.755167

bioRxiv · 10.64898/2026.10.08.755167

TorPause: Efficient Static Organ Preservation for Transplants

Bhadury, J.·Tajima, T.·Suchy, F. P.·Masaki, H.·Zhang, J.·Rivera, M.·Nishimura, T.·Charlesworth, C. T.·Esquivel, C. O.·Nakauchi, H.

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Abstract

Transplantation is limited by how long organs survive outside the body. Existing preservation methods slow metabolism or sustain physiological support, but neither eliminates ischemia-reperfusion injury (IRI), which shortens storage and drives organ discard. Embryonic diapause and hibernation show that mammalian cells retain a latent capacity for reversible metabolic arrest. Screening the PI3K-mTOR axis, we identified a dual inhibitor that pauses embryonic stem cells reversibly at ambient oxygen and holds intact mouse embryos in arrest for 11 days. Combined with a mitochondria-targeted hydrogen sulfide donor, this yields TorPause: a two-component flush pairing metabolic pausing with mitochondrial protection, compatible with existing preservation protocols. In a rat liver transplantation model, TorPause reduced structural injury and improved recipient survival after severe warm ischemic storage, potentially expanding the usable donor pool.

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Bhadury, J., Tajima, T., Suchy, F. P., Masaki, H., Zhang, J., Rivera, M., Nishimura, T., Charlesworth, C. T., Esquivel, C. O., Nakauchi, H.. 2026-10-09. TorPause: Efficient Static Organ Preservation for Transplants. https://doi.org/10.64898/2026.10.08.755167

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