Supercooling was successfully applied to organ preservation at Massachusetts General Hospital/ Harvard Medical School. Livers that were later transplanted into recipient animals were preserved by supercooling for up to 4 days, quadrupling the limits of what could be achieved by conventional liver preservation methods. The livers were supercooled to a temperature of −6 °C (21 °F) in a specialized solution that protected against freezing and injury from the cold temperature.