Yale researchers use tick protein to increase cold resistance in mice

Researchers have successfully transplanted a protein that protects ticks from the cold into mice, opening the door to one day prevent frostbite in humans.

Mice carrying tick protein showed increased resistance to frostbite when exposed to the cold: study

A protein implanted in lab mice increased their resistance to frostbite. Researchers hope to use the protein to increase the life of organs for transplantation, as well as - perhaps - create an "antifreeze" for humans. (Robert F. Bukaty/Associated Press)

A human antifreeze may sound like science fiction, but researchers at Yale University are closing in on a protein that could, one day, render winter coats and protective boots obsolete.

The scientists are primarily interested in a protein produced by ticks, which keeps them from dying of cold as they lay dormant during the winter. Scientists were able to isolate the protein and place it in mice.

A study published in February explained that the mice carrying the tick protein showed increased resistance to frostbite when exposed to the cold — a promising start, according to lead author Martin Heisig.

"It's aiming for therapeutic approaches... for prevention of frostbite, or extending the storage of tissues during organ transplantation," says Heisig. "But so far this is basic research, proving so far that proteins from a tick are functional in a mammalian system." 

Heisig says it's difficult to say whether or not the same effect could eventually be achieved with humans. One roadblock is that researchers still haven't figured out how the cold-resistance protein works.

"There are plenty of other proteins that protect organisms from the cold," says Heisig. "A lot of them bind to the surface of ice crystals, and prevent ice crystals from growing and damaging the cells from their structure.

"But there are a lot of different proteins that can protect cells from the cold, and detailed molecular structure isn't known to the highest detail yet. But a lot of efforts are ongoing to get to know the functional mechanisms better than what we know today."

Heisig and his team have primarily focused on the protein's impact on tissue, with the ultimate end goal of using it to preserve organs for longer during transplant procedures.

But there is still a burning question surrounding this chilly discovery: could this protein be used to protect Canadians from freezing winter temperatures?

"I would love to have a skin ointment protecting us from the cold better," says Heisig. "I don't see that happening with the protein, actually, because I believe it would be too expensive to use."

"But if we were to identify the molecule or mechanism of our protein, then a clever pharmacist or a chemist could phenocopy this into a chemical substance, which could be synthesized. That might be a highly functional way to utilize the function of a tick protein, without actually needing the protein.

"That's totally possible."