Long-term storage solution for transplants may now be closer

Ice-binding proteins, discovered some 50 years ago in Antarctic fish, are now known to exist in cold-resistant fish, plants, insects and microorganisms.

By JUDY SIEGEL-ITZKOVICH
Lab technician using microscope (photo credit: INGIMAGE / ASAP)
Lab technician using microscope
(photo credit: INGIMAGE / ASAP)
Scientists at the Hebrew University of Jerusalem believe that after decades of studies, they have made a breakthrough in efforts to preserve body tissue and organs for transplantation.
Currently, a heart or lung can be kept viable for only six hours before deterioration begins. A liver or pancreas will go to waste after 12 hours in storage, and a kidney can be kept outside the body for only up to 30 hours.
“We investigate the interaction of ice-binding proteins with ice crystals,” said Prof. Ido Braslavsky, from the Hebrew University’s Institute of Biochemistry, Food Science and Nutrition at the Robert H. Smith Faculty of Agriculture, Food and Environment.
“The ability to freeze organs and thaw them without damaging them would be revolutionary in terms of our chances to save lives.”
One of the main problems preventing the storage of organs for more than a few hours is the growth of ice – when organs are frozen, ice crystals expand and damage cells until they can’t be revived.
To this end, Braslavsky is investigating the interaction of ice-binding proteins with ice crystals, and together with his team – which includes Dr. Maya Bar Dolev, Dr. Liat Bahari, Dr. Amir Bein, Dr. Ran Drori, Dr. Victor Yeshunsky and Prof. Peter Davies from Queens University in Kingston, Ontario – he is studying anti-freeze proteins that help organisms resist or withstand freezing both at sea and on land.
“Since we are working at temperatures of sub-zero Celsius degrees and we need high accuracy of working temperature, we designed a specialized microscope with a stage cooler that allows a millidegree-level control of temperature and also freezing,” Braslavsky said.
“Using fluorescent illumination, we can see where the proteins, which are tagged with fluorescent dyes, are located. With these devices, we can follow ice crystals as they grow and melt in the presence of ice-binding proteins.”
Perfecting cryopreservation – the process of preserving cells, tissues and organs in sub-zero temperatures – would enable long-term banking of tissues and organs and efficient matching between donor and patient, eventually saving the lives of millions of people around the world, he added.
Ice-binding proteins, discovered some 50 years ago in Antarctic fish, are now known to exist in cold-resistant fish, plants, insects and microorganisms.
They actively inhibit the formation and growth of crystalline ice, and their superiority over other anti-freeze substances is that they are needed in very low amounts to do it effectively.