Organ banks have long seemed like the stuff of science fiction. While the technology to freeze or vitrify hearts, lungs, kidneys and other bodily tissues has existed for decades, scientists for just as long have struggled to find a way to “warm up” organs for transplant surgeries, among other uses.
As a result, organs placed on ice have short shelf lives, lasting only a matter of hours before expiration. Today, more than 60 percent of the hearts and lungs donated for transplantation are discarded for this reason. This means patients end up on waiting lists that, depending on the organ, stretch months, if not years
into the future.
However, a research team led by the University of Minnesota announced Wednesday that it made a groundbreaking discovery in the organ “warming” process that could help make organ banks possible and potentially eliminate organ donor waiting lists altogether. The U called the research “a major step forward in saving millions of human lives” through the improved preservation and accessibility of organs.
John Bischof, a mechanical engineering professor at the university and senior author of a report published Wednesday in the Science Translational Medicine
research journal, described the issue facing the medical industry as “a frozen dinner problem.”
“In the 1990s, people tried to just throw [organ tissue] into a microwave oven and reheat it,” he said. “But the problem with that is you get thermal runaway and you get the same problems you get with your frozen TV dinners, and that is that the microwave doesn’t uniformly work through the material.”
Most often, the organ tissue would suffer major damage during the rewarming process, rendering it unusable. So Bischof and his research team took a different approach, instead using an emerging technology known as nanowarming. Through the use of magnetic nanoparticules as tiny heat sources, the research team managed to successfully rewarm large-scale animal heart valves and blood vessels preserved at extremely low temperatures.
“Nobody has attempted anything like this and been successful,” Bischof said of the discovery. “Currently, there is no equipment in this field that can do what we’ve done. So this is truly filling a void.”
Previous experiments in organ warming failed to warm the entire organ or, in cases of where samples were rewarmed over ice or using heat convection, the organ tissue would crack, similar to an ice cube dropped in hot water.
The new method led fellow researchers in the field, as well as the University of Minnesota, to describe the process and technology developed by Bischof and his team as “revolutionary.”
Bischof believes the technology has implications beyond warming organs: He also believes it might be able to treat cancer. His initial work with nanowarming, he said, was actually aimed at using it to damage tumor cells.
“The rule is any time you can cool or heat beyond the physiological range, you may have some preservative impact and you may also destroy,” Bischof said. “So if we can get [these nanoparticles] into cancer, then we can also use them to treat cancer.”
This concept, in fact, has been around for a number of years. MagForce, a biotechnology company in Berlin, is one such pioneer in the field of nanotechnology-based cancer treatments. A number of its products have European approval, and it is looking to bring its NanoTherm therapy to market here in the United States.
With Bischof and his team’s discovery, the University of Minnesota will hold two patents: one on the applicant (mesoporous silica iron oxide) used in the nanowarming process, and another on how the nanoparticles are deployed.
University grants, as well as money from the National Science Foundation, National Institutes of Health, and the U.S. Army Medical Research and Material Command, funded the research.
Bischof emphasized the team aspect of the discovery, specifically calling out Zhe Gao and Navid Manuchehrebadi—post-docs that were co-first authors—saying that they “put their heart and soul into this, and I couldn’t have done it without them and the rest of the collaborators.”
Others that contributed to the report include post-doctoral researchers Jin Jin Zhang, Hattie Ring and Qi Shao, graduate student Feng Liu; undergraduate student Michael McDermott; dentistry professor Alex Fok; radiology professor Michael Garwood; chemistry professor Christy Haynes. Outside of the University of Minnesota, the research team received help from Carnegie Mellon University’s mechanical engineering professor Yoed Rabin and Clemson University bioengineering professor Kelvin Brockbank, as well as North Charleston, South Carolina-based Tissue Testing Technologies LLC.
Bischof added that his research team’s discovery was something, he believes, was possible because of the University of Minnesota’s diversely trained staff and open, collaborative environment.
“I think companies try to create this, but your borders are limited at a company. Here, at the U, you don’t have a border,” he said. “We used to talk about universities being a marketplace of free ideas. Of course, some of that is changing with intellectual property and the need to commercialize, but I can call up anybody I want and say ‘hey do you want to collaborate?’ Essentially, this whole project started with a lunch or a coffee.”
Navid Manuchehrebadi, Zhe Gao and John Bischof (left to right).