9 Jun 2023

Vitrified rat kidneys rewarmed by nanowarming survive 30 days after transplant

Biotechnology and synthetic biologyMedical technology and bioelectronics
AI illustration · Illustrative scene, not a photograph of the specific device or experiment.

What was demonstrated

In a rat model, whole kidneys were vitrified (cooled to an ice-free, glass-like state), stored at about -150 degrees C for 1 to 100 days, and rewarmed by nanowarming, which heats magnetic nanoparticles in the organ's blood vessels with a magnetic field. Five nanowarmed kidneys were transplanted into nephrectomised recipients, alongside five fresh-control transplants. All nanowarmed and fresh-control recipients survived the 30-day study. Nanowarmed kidneys produced urine within 40 to 45 minutes of reperfusion, compared with a few minutes for fresh controls. Day-30 creatinine was 0.62 plus or minus 0.24 mg/dL for nanowarmed kidneys and 0.44 plus or minus 0.19 mg/dL for controls (P = 0.3). Estimated GFR at day 30 was 2.2 plus or minus 0.8 mL/min and 2.7 plus or minus 0.7 mL/min respectively (P = 0.421).

Why it matters

Whole-organ vitrification has been hard because both cooling and rewarming must be fast enough to avoid ice damage. This study suggests that nanowarming may allow a vitrified kidney to recover and work after transplant, although it was tested in one organ type in a small animal model.

Caveats

  • Tested in rats with small groups (five nanowarmed and five fresh-control recipients), not in human-sized organs.
  • Recipients were followed for 30 days only, so long-term graft survival and immune response were not assessed.
  • Nanowarmed kidneys had 2 to 3 weeks of initial graft dysfunction, which the authors note might have been treated with dialysis in some clinical settings.
  • Storage was tested for up to 100 days, and the nanowarmed kidneys were not fully compared with standard 36 to 48 hour cold storage.

Technology profiles

Sources

  1. peer reviewed paper
    Vitrification and nanowarming enable long-term organ cryopreservation and life-sustaining kidney transplantation in a rat model
    Zonghu Han, Joseph Sushil Rao, Lakshya Gangwar et al.. Nature Communications, 9 Jun 2023. DOI: 10.1038/s41467-023-38824-8.

Last reviewed 21 Oct 2026.