# Whole heart suspended animation: leveraging the zebrafish to solve the organ shortage

> **NIH NIH R00** · MASSACHUSETTS GENERAL HOSPITAL · 2022 · $249,000

## Abstract

There are currently over 123,000 patients on the organ transplant waiting list in the US, a number that far exceeds
the supply of available organs, and that continues to grow ~5% each year. In Canada, every ten minutes
someone is added to the waitlist and ~22 people die each day while waiting for a transplant. A major reason is
the limitations of our current organ preservation and handling practices, which severely restricts preservation
duration and disallows the transplantation of marginally injured organs. This project aims to develop a protocol
to bank hearts for several weeks to enable global organ matching and overcome limitations of ischemia tolerance
to increase the donor pool of hearts.
I propose that strategies to solve current barriers in heart transplantation, including ex vivo preservation and
recovery of marginal organs, should look to nature for inspiration. More specifically, the ability to descend into a
state of “suspended animation”, characterized by the slowing of life processes and improved stress tolerance,
holds promise. I will systematically leverage two methods of suspended animation; 1) freeze-tolerance, and 2)
high-temperature hibernation. Using inspiration from freeze-tolerant wood frogs in nature, I seek to develop a
protocol for whole heart preservation which will achieve high subzero storage temperatures in the presence of
extracellular ice, and storage durations of weeks to months. Further, I will identify pharmacological agents which
will strategically lower metabolic demands to match oxygen/nutrient availability, and increase warm ischemia
tolerance from minutes to hours, using inspiration from hibernating primates in nature.
To accomplish this goal, I propose to introduce the zebrafish as a novel model system for cryobiology and
organ transplantation. While zebrafish has become a favored research animal for studying human disease, it
has never been used as a tool to develop innovative approaches for organ handling and preservation or to
understand the underlying biology of organ transplantation. Classical model organisms such as the zebrafish
offer many advantages including robust genetic/biochemical tools, ease of real-time imaging, compatibility with
high-throughput studies, and are cheap and easy to maintain. Complimented by scale-up experiments and
validation in mammalian model systems, including rats, the present proposal will mend a critical gap in the
research field.

## Key facts

- **NIH application ID:** 10366091
- **Project number:** 5R00HL143149-04
- **Recipient organization:** MASSACHUSETTS GENERAL HOSPITAL
- **Principal Investigator:** Shannon Noella Tessier
- **Activity code:** R00 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $249,000
- **Award type:** 5
- **Project period:** 2021-04-01 → 2024-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10366091

## Citation

> US National Institutes of Health, RePORTER application 10366091, Whole heart suspended animation: leveraging the zebrafish to solve the organ shortage (5R00HL143149-04). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10366091. Licensed CC0.

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