Jan 29, 2026 · 30m · no-priors
How Until is Engineering Away Time in Organ Transplants | Laura Deming
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In this episode of No Priors, Laura Deming, CEO of Until, explains how first-principles physics and advanced thermal engineering are making reversible cryopreservation viable, starting with organ transplant banking and paving the way for whole-body medical hibernation.
How this conversation actually went
Every chapter scored 0–10 on four independent dynamics. Hover any point for the reasoning behind the score. The hosts hold 23.6% of the talking time here. How this is scored →
The hosts as informed peer 3.8 Guest teaching 4.3 Guest disagreement 1.1 The hosts pushing back 1.1
speaking balance: gold is the hosts, purple is the guest (3 minute bins)
Sharpest disagreement ▶ 11:07 Pushing back on recreational time-travel
Deming firmly redirects Guo's hypothetical Mars travel use case, arguing that the social reality of abandoning everyone you know renders non-medical hibernation impractical.
Hardest push from the hosts ▶ 25:02 Challenging why the field sat neglectedGuo questions why mainstream science neglected cryobiology for decades if proven empirical milestones like viable re-implanted kidneys already existed.
Biggest teaching moment ▶ 13:40 Explaining probabilistic ice nucleationDeming walks through the fundamental physics of stochastic ice nucleation, showing how rapidly passing danger temperature thresholds prevents destructive crystal growth.
The host holds their own ▶ 18:05 Synthesizing engineering levers in organ vitrificationGuo demonstrates strong technical comprehension by articulating how adjusting geometric heating ratios and thermal distribution replaces purely biological interventions.
the scores for every segment, with the reasoning behind each
| Chapter | Topic | The hosts as informed peer | Guest teaching | Guest disagreement | The hosts pushing back | Why |
|---|---|---|---|---|---|---|
| Episode Preview: Engineering Away Time Through Cryopreservation | 3 | 4 | 1 | 1 | Guo sets up the episode and asks Deming about her unconventional childhood and early conceptualization of aging. Deming explains how she realized longevity wasn't a fixed ceiling but an uncertain variable worth investigating. | |
| Founding the Longevity Fund and Shifting Focus to Cryopreservation | 3 | 3 | 1 | 1 | Guo asks what prompted the shift from venture capital at the Longevity Fund to founding Until. Deming describes cryopreservation as a foundational problem and details how her co-founder re-derived principles to confirm technical feasibility. | |
| Until's Core Mission: Medical Hibernation as Critical Care | 3 | 4 | 1 | 1 | Deming outlines Until's core mission of creating an 'ambulance for the future' through medical hibernation, distinguishing near-term organ preservation from long-term whole-body applications. | |
| The Social Reality and Psychological Costs of Time-Skipping | 4 | 4 | 2 | 2 | Guo raises sci-fi use cases like space travel to Mars, but Deming grounds the discussion in the severe psychological and social costs of leaving one's social network behind in time. | |
| Physics of Ice Nucleation and Empirical Precedents in Cryopreservation | 4 | 6 | 1 | 1 | Deming educates Guo on the stochastic physics of ice nucleation and notes existing precedents like human embryos preserved for over 30 years to prove that the core physics works. | |
| Trading Engineering Levers Against Biological Toxicity | 6 | 5 | 1 | 2 | Deming details how engineering controls over temperature allow teams to reduce toxic cryoprotective agents. Guo synthesizes the concept with concrete lab observations about surface-area-to-volume heating. | |
| Dual Research Tracks and the Open Question of Brain Preservation | 4 | 5 | 2 | 1 | Deming outlines their parallel rat and human organ research tracks, candidly noting that brain preservation remains a major scientific unknown and defining practical transplant milestones. | |
| Validating Cryobiology and Shifting Mainstream Perceptions | 4 | 5 | 1 | 1 | Deming highlights historical precedents by Greg Fahy and John Bischof to show organ vitrification is scientifically grounded, explaining the field's antimemetic reputational hurdles. | |
| Revolutionizing the Transplant Ecosystem for Patients and Surgeons | 3 | 3 | 0 | 0 | The interview concludes with Deming describing how removing time constraints liberates organ transplant logistics, before sharing her aesthetic passion for representing the molecular world. |
Statements from this episode (12)
Deming: Society's failure to recognize aging as a disease hinders research
“I think longevity and aging kind of occupy this weird realm where because they're not like explicitly diseases in a way that's fully socially recognized yet, they're not seen as valid to work on.”
Co-founder Hunter Davis re-derived statistical mechanics for Until's cryopreservation guide
“Hunter went back and like re-derived fundamental laws of stat and mech as part of like, this is what you should know in craft preservation doc.”
Deming: Immunotherapy raised metastatic melanoma ten-year survival to over 50 percent
“Like sort of in a single year, like metastatic melanoma went from being something that you had like a six to nine month prognosis, like less than a year of expected survival, to with like, you know, new combination immunotherapies, you might have a decade plus…”
Until aims for reversible whole-body cryopreservation after mastering single organ transplants
“Our long-term goal is reversible whole body cryopreservation for, you know, medical sort of hibernation. But in the near term, what we work on is reversibly cryopreserving human, single human organs to help transplant patients get organs more efficiently.”
Deming: Medical hibernation carries severe psychological costs of losing social context
“And that will put a limit on, like, how much people want to use this for, like, I think there's, like, a real cost that, that kind of you incur. And so it's, in my mind, it only makes sense for, like, really serious use cases initially where, like, you literal…”
Deming: Speeding through nucleation temperature ranges prevents tissue ice formation
“Ice sort of forms through a process of random nucleation and then extension. And this is cool because you can modulate the, like, sort of nucleation, the rate of nucleation and extension to then modulate the probability of ice formation. And because it's proba…”
Deming: Human embryos cryopreserved for over thirty years yield viable pregnancies
“There have been human embryos that were reversibly, that were, you know, cry preserved for the latest record was over 30 years, and then rewarmed and sort of viably used to create pregnancy, and then, you know, sort of like, there are kids who were literally c…”
Deming: Cryobiology uniquely allows swapping biological complexity for engineering difficulty
“Not specific or something, but it is actually one of the core reasons why I think the problem is interesting to work on, which is that, like, you can trade off, like, engineering difficulty and biological difficulty to a non-zero degree. Like, not, not a hundr…”
Until simultaneously develops human organ cryopreservation and reversible whole-rat hibernation
“We work on the two in parallel. So we both work on scaling up preservation and rewarming technologies to kind of human organ scale. And also in parallel, we work on a sort of whole rat reversible hibernation and transitioning technologies over from sort of wha…”
Deming: Brain injury tolerance remains the bottleneck for whole-body cryopreservation
“The big unknown to get to whole body reversible is the brain. It's unclear, like the brain can withstand a lot of change and does withstand a lot of different types of damage or change with age, for example. But it's unclear whether, like, what kind of injury …”
Deming: Rewarmed cryopreserved kidneys successfully restore normal organ function in rats
“Greg Faheed has done excellent work sort of looking at reversible cryopreservation in kidneys, and showing, like, you can reversibly cryopreserve a kidney, rewarm it, put it into a rat that does not have another kidney, and that rat returns to normal function …”
Deming: Organ transplantation is severely bottlenecked by last-minute travel logistics
“Right now for matching, it's like everything's done at literally the last minute. It's like someone Dies and organ becomes available. And like, you're just kind of calling around trying to find, like, what patient is available to get this organ, and you don't …”