Supercooling extends preservation time of human livers

Area of Science:

• Transplantation Medicine
• Organ Preservation
• Cryobiology

Background:

• Limited preservation time of vascular organs hinders transplantation success.
• Current hypothermic preservation (4°C) restricts liver viability to under 12 hours.
• Previous supercooling methods showed promise in rat livers but face challenges with human organs due to ice formation.

Purpose of the Study:

• To develop an improved supercooling protocol for extended human liver preservation.
• To overcome limitations of ice nucleation in scaling supercooling to larger organs.
• To assess the viability and transplant readiness of supercooled human livers.

Main Methods:

• Minimizing ice nucleation sites and using protective agents during machine perfusion.
• Implementing homogeneous preconditioning with protective agents.
• Storing human livers at -4°C using supercooling followed by subnormothermic machine perfusion.

Main Results:

• Successfully stored human livers at -4°C using the improved supercooling protocol.
• Extended ex vivo liver viability by 27 hours.
• Demonstrated unchanged liver viability post-supercooling and ability to withstand simulated transplantation stress.

Conclusions:

• The novel supercooling protocol effectively prevents freezing in human livers.
• This method significantly extends the preservation time of human livers for transplantation.
• Supercooled livers maintain viability and are suitable for subsequent normothermic reperfusion and transplantation.