Article brought to you by: Catholic Online (www.catholic.org)

Freezing human organs for later transplantation closer to reality

By Catholic Online (NEWS CONSORTIUM)
November 6th, 2013
Catholic Online (www.catholic.org)

The transplantation of human organs always carries a high amount of risk. Available organs from donors must be quickly identified, and technicians must race the organs to patients at hospitals many miles away. Time is of the essence. The ability to freeze human organs would be a godsend, but is currently not feasible. Now - researchers are bringing this process closer to fruition.

LOS ANGELES, CA (Catholic Online) - Researchers from Villanova University have now discovered how ice crystals invade and damage biological material during the freezing process. Once this obstacle is surmounted, freezing complex human tissues such as donor organs could be a very real option for physicians.

Called "cryopreservation," the procedure involves cooling human tissues to sub-zero temperatures. While this frozen state effectively blocks chemical reactions from happening and lets them remain viable for medical use later on.

"If you can cryopreserve tissue or even organs, then you have a way of storing them and of transporting them," senior author Dr. Jens Karlsson, of the department of mechanical engineering at Villanova University says.

"Now if you want to do a (lung) transplantation, you're rushing the harvest organ from one hospital to another by helicopter, and you only have a few hours to do it. But if you're able to preserve the tissue, then you have as much time as you want and you can really find the best match for the tissue and transport it over much longer distances."

Cryopreservation is currently a risky process, only reserved for the conservation of smaller groups of tissues or individual cells, such as embryos and stem cells.

Freezing larger biological tissues is far more cumbersome, as these materials often contain large amounts of water, which form ice crystals when frozen. This causes significant damage to the cells and tissue.

In order to find out how ice interacts with cells as they freeze, Karlsson and his team utilized a video cryomicroscrope. The process allowed them to observe the freezing process using high-speed imaging.

"We could record what happens and play it back in slow motion and really see in great detail what the interactions are between the ice, and cells in the tissue," Karlsson said.

The team then monitored the freezing events of genetically modified cells, some of which contained certain junction proteins and some of which did not. These junction proteins either suppressed or encouraged the formation of the cells' gap junctions and tight junctions- channels that connect adjacent cells together.

Gap junctions. On the other hand directly connected the cytoplasm of two cells, while tight junctions provide an even closer connection by firmly stitching together the cells' plasma membranes.

The researchers found that when the gap junctions were suppressed in the cells, the ice still spread freely throughout the tissue. Extremely snug tight junctions played a significant role in allowing the ice to infiltrate the cells.

A birth foretold: click here to learn more!

Article brought to you by: Catholic Online (www.catholic.org)