# Organ banking for transplant—kidney cryopreservation by vitrification and novel nanowarming technology

> **NIH NIH R01** · UNIVERSITY OF MINNESOTA · 2020 · $584,501

## Abstract

ABSTRACT:
 Organ banking has the potential to revolutionize the way organs are used for transplantation. Rewarming
organs such as kidneys from the vitrified state is a critical step in obtaining successful cryopreservation. This
would allow improved allocation, transport, and recipient preparation prior to transplant, while simultaneously
providing a missing link in the potential supply chain for other engineered tissues. Typical freezing processes
cause significant damage to biomaterials through ice crystal formation and cellular dehydration. However, with
the aid of cryoprotectant (CPA) solutions, biospecimens can be stabilized in the vitreous (i.e. “glass” or
“amorphous”) or ice free state, allowing for long-term cryopreservation. Our collaborator and consultant Dr.
Greg Fahy has been able to vitrify rabbit kidneys since the 1980s. However, successful rewarming of these
vitrified kidneys has remained a challenge to translation of vitirification for organ banking. Specifically,
achieving critical warming rates (tens to hundreds of oC/min) necessary to avoid devitirification (i.e.
crystallization) during warming has not been possible. In addition, achieving these rates in a sufficiently uniform
fashion throughout the organ is also required to avoid thermal stresses that can crack the brittle material, and
so both speed and uniformity of warming are of critical importance.
 Here we propose to investigate the ability of radiofrequency heated magnetic nanoparticles, or
“nanowarming,” to overcome this major limitation hindering further development of bulk cryopreservation of
kidneys. Although electromagnetic rewarming has been tried, the direct coupling of the waves to tissue will
inherently result in non-uniformity in heating, which leads to crystallization, cracking and differential viability. At
lower radiofrequencies (RF < 1 MHz) alternating magnetic fields (AMFs) can uniformly penetrate tissues
without attenuation and negligible dielectric coupling. Although these lower frequency fields will be unable to
rapidly heat the tissue on their own, they are able to produce significant heating through coupling with
magnetic (e.g. iron-oxide) nanoparticles. We have already demonstrated that this approach can generate
heating rates rapid enough to avoid devitirification in most CPAs of interest (up to 200 oC/min) and should
scale independent of sample size.
 The objective of this study is to refine this novel nanowarming technology for use in cryopreserving kidneys
for transplant. To this end, in Aim 1 we will physically characterize CPA and nanoparticle mixtures to heat
rabbit and larger mammalian kidneys. In Aim 2 we will demonstrate our ability to perfuse this CPA and
nanoparticle combination into rabbit kidneys, vitrify and nanowarm while maintaining viability, cellular function
and structural tissue integrity. Finally, in Aim 3 we will demonstate in vivo function after vitrification and
nanowarming by transplant in rabbits and scaling for use in hum...

## Key facts

- **NIH application ID:** 9912760
- **Project number:** 5R01DK117425-03
- **Recipient organization:** UNIVERSITY OF MINNESOTA
- **Principal Investigator:** JOHN C BISCHOF
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $584,501
- **Award type:** 5
- **Project period:** 2018-04-13 → 2022-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9912760

## Citation

> US National Institutes of Health, RePORTER application 9912760, Organ banking for transplant—kidney cryopreservation by vitrification and novel nanowarming technology (5R01DK117425-03). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/9912760. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*