Heiko Yang, MD, PhD, assistant professor of urology in the University of Colorado Anschutz Department of Surgery, has received a grant from the National Institutes of Health (NIH) for further research on his discovery of a product that has the potential to revolutionize the way deceased donor organs are kept alive prior to transplant or research.
“In a nutshell, we have derived a blood substitute from earthworms to keep human and animal kidneys alive outside the body,” Yang says. “Currently, most organs are kept alive using donor blood, but blood is expensive, has a short shelf life, and degrades quickly during machine perfusion. As it turns out, earthworms have a very shelf-stable hemoglobin-like oxygen carrier that has a number of properties that make it favorable for kidney perfusion.”
Perfecting perfusion
Yang, who conducts research on perfused organs, says he has long looked for a substitute for red blood cells, which release toxic chemicals when they burst, to use in the perfusion system that uses an artificial lung and heart to keep organs viable.
“I eventually connected with Jake Elmer, PhD, at Villanova University, who has been working with earthworm hemoglobin, and we did some pilot studies and saw that you can actually keep kidneys alive with this earthworm material,” he says. “The basis of this grant is to explore how we can optimize this use and see if we can keep kidneys and other organs alive this way. We want to find out what's the best concentration to use, if we need to stabilize it chemically, and if we can get a kidney to survive for several days on this material that contains no red blood cells.”
Suitable substitute
The two-year, “high-risk, high-reward” NIH grant is designed so that Yang and his co-researchers can apply for further funding once they have refined and proved their concept. If all goes as planned, it could be a significant advance for medical research, Yang says.
“It’s really exciting on several levels,” he says. “There are a lot of problems when we rely on blood to do our experiments — the content, the quality, having it readily available. This solves those problems for the general medical community. People have been looking for blood substitutes for decades, but none of them have panned out. So we still rely on donated blood products and red blood cells to save lives. This brings us one step closer to creating a viable blood substitute.”
Transplant triumph
The discovery may also be a boon to clinicians and surgeons in transplant medicine, he says, who currently must rely on a variable and inconsistent blood supply when keeping organs alive prior to transplant.
“There's the whole field of organ perfusion related to transplantation medicine, where people are trying to keep organs alive outside of the body to extend their viability and get donor organs to recipients more efficiently,” he says. “They're running into the same limitations that we've been running into, so having something like this could impact that field in a major way. Rather than getting blood from blood banks, why can't we just use something that's off the shelf, that you can store for a long period of time, and it just works?”