Now researchers have demonstrated a method that kept rat livers viable up to four days.

 

The scientists lowered the livers to below freezing temperatures, while flooding the tissue with antifreeze chemicals to prevent the formation of damaging ice crystals.

 

But such cooling alone is not sufficient, due in part to the liver’s wide variety of cell types and functions. So the researchers also used machine perfusion: as the livers were cooled they were flushed with solutions that kept them operational. They were perfused again as they were brought back to above-freezing temps.

 

All the rats that were implanted with 3-day-old livers survived for three months. Nearly 60 percent of the rats with four-day-old livers survived. In contrast, no rats that received 3- and 4-day-old livers preserved by currently used methods survived.

 

This work is an early step toward creating a system that could work in humans, which would dramatically improve the chances of getting organs to people who desperately need them.