# Until Labs **Entity class:** Company **Domain:** Organ Cryopreservation / Reversible Biostasis **Doc Type:** Company Node **Maturity:** Preclinical **Collection:** [[collections/Neurotech|Neurotech]] · [[collections/Consciousness Continuity|Consciousness Continuity]] **Primary Sources:** [[research/Research Inferences Integration Report - 2026-10-23|Research Inferences Integration Report — 2026-10-23]] ## Definition **Until Labs is a San Francisco company developing organ-scale reversible cryopreservation: cooling a donor organ to a temperature that allows indefinite storage, then rewarming it intact for transplant.** It was founded as Cradle by Laura Deming and Hunter Davis, emerged from stealth with $48 million in seed funding, and closed a $58 million Series A on 23 September 2025 led by Founders Fund with Lux Capital and Field Ventures participating. Company-reported total funding exceeds $100 million. Its stated long-term goal is whole-body reversible cryopreservation as a foundation for medical hibernation. ## Technical program The work spans perfusion hardware, cryoprotective agent chemistry and rapid rewarming infrastructure, with a team drawn from chemistry, biology, engineering, neuroscience and surgery. Reporting describes progression from neural slices toward preclinical kidneys, hearts, lungs and livers; that staging comes from a recruiting aggregator rather than the company, and is recorded here as unverified. ## Why it matters to the corpus Transplant organ banking requires exactly the perfusion, vitrification and rewarming technology that whole-brain preservation requires, and it has immediate medical demand behind it. That makes Until Labs the clearest instance of the register's adjacent-funding reading: a market with paying customers underwriting the physical chemistry that continuity work depends on. The binding constraint it attacks is the same one that limits preservation quality in [[wiki/Aldehyde-Stabilized Cryopreservation|aldehyde-stabilized]] and vitrification protocols, namely the trade between ice damage and cryoprotectant toxicity, and the uniform rewarming that large tissue volumes have never tolerated well. ## Open Questions - Published, peer-reviewed results at whole-organ scale with post-thaw function. - Whether a reversibly preserved organ reaches a transplant trial, and in which organ first. - Whether the whole-body program is pursued as medicine or as biostasis, and under what regulatory category. ## Research Inferences These entries translate the forward-looking register in [[research/Research Inferences|Research Inferences]] into ordinary wiki prose. The tier labels apply to the inference, not automatically to every factual anchor inside it. Proposed IDs above INF-0500 come from the 2026-10-23 cycle: [[research/Research Inferences Integration Report - 2026-10-23|Research Inferences Integration Report — 2026-10-23]] · [[research/Research Inferences Integration Audit - 2026-10-23|Research Inferences Integration Audit — 2026-10-23]]. - **INF-0235 — Strongly indicated.** Transplant organ banking requires exactly the perfusion, vitrification, and rewarming technology that whole-brain preservation requires. A medical market with immediate demand is funding the physical chemistry that continuity work depends on, which is the most reliable form of technological carry. - **INF-0234 — Established.** Cryoprotectants prevent ice damage at the cost of chemical toxicity, and the trade-off is the central technical problem in the field. Improvements in cryoprotectant chemistry propagate directly into organ banking, which gives the research a large non-continuity funding base. - **INF-0236 — Plausible.** Uniform rewarming using magnetic nanoparticles solves the cracking and devitrification problem that has limited large-tissue cryopreservation. Successful rewarming at organ scale would make reversible whole-brain preservation a research target rather than a thought experiment. - **INF-0447 — Plausible.** Induced torpor research funded for trauma care and spaceflight would extend viable suspension windows without freezing. A pharmacological pause is the intermediate technology between emergency medicine and preservation, and it has independent funding. - **INF-0233 — Plausible.** Preserving now and reading later decouples the acquisition timeline from the individual's lifespan, which converts continuity from a race against biology into a storage commitment. Preservation is the only continuity intervention available to people alive today. ## Relationships - **founded_by:** Laura Deming and Hunter Davis; formerly named Cradle. - **investors:** Founders Fund (lead), Lux Capital, Field Ventures; [[wiki/Peter Thiel|Peter Thiel]] co-founded Founders Fund, which also backs [[wiki/Neuralink|Neuralink]]. - **adjacent_funding_for:** [[wiki/Brain Preservation|Brain Preservation]] · [[wiki/Cryopreservation|Cryopreservation]]. - **technique_peers:** [[wiki/21st Century Medicine|21st Century Medicine]] · [[wiki/Aldehyde-Stabilized Cryopreservation|Aldehyde-Stabilized Cryopreservation]] · [[wiki/Nectome|Nectome]]. - **longevity_adjacency:** [[wiki/Longevity Escape Velocity|Longevity Escape Velocity]]. - **cluster_home:** [[wiki/Deep Time Continuity|Deep Time Continuity]]. - **ecosystem:** [[wiki/Neurotechnology Ecosystem|Neurotechnology Ecosystem]] · [[collections/Neurotech|Neurotech]]. ## Sources - [Until Labs secures $58M to advance organ cryopreservation technology — HLTH, 23 September 2025](https://hlth.com/insights/news/until-labs-secures-58m-to-advance-organ-cryopreservation-technology-2025-09-23) - [Cryopreservation startup lands $58m to "pause biological time" — Longevity.Technology, 2025](https://longevity.technology/news/cryopreservation-startup-lands-58m-to-pause-biological-time/) - [Fenwick represents Until Labs in $58M Series A funding](https://www.fenwick.com/insights/experience/fenwick-represents-until-labs-in-58m-series-a-funding) - [Continued progress towards reversible vitrification of organs — Fight Aging!, October 2025](https://www.fightaging.org/archives/2025/10/continued-progress-towards-reversible-vitrification-of-organs/) As of 23 October 2026.