Israeli scientists have successfully froze, thawed, and transplated a liver from one pig into another. The technology developed at the Agricultural Research Organization in Bet-Dagan, and now pursued by Core Dynamics, an Israeli company also based in Orangeburg, NY, uses slow, controlled cooling of tissue to preserve it for future use.
From The New Scientist:
Arav and his colleagues flushed the blood from the pig’s liver, cooled it, and then encased it in a pair of hollow brass cooling blocks attached to a supply of liquid nitrogen. The device was developed by Core Dynamics, a company Arav co-founded in Ness Ziona, Israel. This cooled the liver at a rate of 0.3 °C per minute bringing it to a temperature of -20 °C in about an hour and a half.
The team then immediately let the liver thaw for 20 minutes before transplanting it into another pig, plumbing it in as a second liver. There it rapidly recovered its red colour, an indication of blood flowing through it, and began producing bile – both signs of health and normal function. The pig was then killed after about 2 hours and the auxiliary liver analysed, revealing that the cells were alive (Rejuvenation Research, DOI: 10.1089/rej.2008.0706).
Here’s what we were able to find about Core Dynamics’ Multi Thermal Gradient™ (MTG) Freezing Technology:
The MTG technology, also known as directional freezing, allows precise control over ice crystal propagation during the freezing process, thereby substantially reducing the mechanical damage caused to cells during freezing. The technology is based on moving the biological material through linear temperature gradients at predetermined velocities. The technology can be used for cells, using rapid velocities, or for organs and tissue, using very slow velocities.
A major advance provided by this Core Dynamics technology is the ability to freeze cells without the commonly used penetrating cryoprotective agents such as DMSO or glycerol. The materials frozen in this fashion may then undergo sublimation of the ice crystals leaving a dry material, the process known as freeze-drying.