Harvard Starts Heart Outside Body, Preserves Organs for 10 Days
Science fiction is fraught with mad scientists who discover strange chemicals that can empower the human body or even reanimate the dead. Well, Harvard has come about as close to that scenario as anyone would want them to. Prof. Hemant Thatte has developed a cocktail of 21 chemical compounds that he calls Somah, derived from the sanskrit for "ambrosia of rejuvenation". Using Somah, Thattle and his team have accomplished some amazing feats with pig hearts. They can keep the organ viable for transplant up to 10 days after harvest - that's incredibly longer than the 4 hour limit seen in hospitals today. Not only that, but using low temperatures and Somah, they were able to take a pig heart that was removed post mortem and get it to beat 24 hours later in the lab. Watch that amazing video after the break.
We've seen amazing chemical treatments that have the potential to transform the medical industry. Mark Roth is working with hydrogen sulfide to put soldiers and other trauma victims into suspended animation on the way to hospitals. The University of Bristol uses xenon gas and low temperatures to prevent brain damage caused by oxygen deprivation. Now Somah could help preserve organs for more than a week outside the body. As researchers continue to unlock the mysteries of your body's chemistry, they may find more ways of preserving and protecting it indefinitely. This will make it much easier to repair or replace parts of your body as they fail, letting you live longer, and healthier. Maybe indefinitely.
Thousands of patients waiting for an organ transplant die each year in the US alone. Donated organs are limited in availability by distance and time. After harvesting, a heart has just about 4 hours to reach its recipient, anything more than that and decomposition will render the heart nonviable. If we could extend that window to 10 days, almost any organ could be made available to almost anyone, anywhere. That will lead to many saved lives. It will also lower costs as there would be no need for chartered jets and other speedy transports.
Somah may also save lives by extending the number of viable heart donors. Now, most of these organs are harvested from patients who are brain dead, but with a beating heart (effectively still alive as far as the body is concerned). After death, cells begin to degrade quickly. If a donor arrives to a hospital DOA, their organs may not be available to transplant to needy recipients. Somah, however, has been shown to reverse some of this cell decay. The chemical cocktail helps transform metabolic agents into preservative agents. Thatte's team took a pig heart harvested post mortem and let it sit in Somah for 24 hours at lower temperatures. The cell degradation was very low. They then warmed the heart up, hooked it into an artificial circulatory system and got it to beat. This clip is brief, but it shows the incredible achievement:
To better understand if and how Somah preserved a heart, Thatte and his group harvested two female pig hearts and placed them in two different containers. One was filled with Somah, the other with Celsior from Genzyme - the standard chemical bath which preserves organs in hospitals today. As described in the journal Circulation, the team took tissue samples every four hours from each heart. They found that the Somah heart had a much lower rate of cell decay, including important cardiomyocyte and endothelial cells which are necessary for the heart to work in a new host. Based on this research they concluded that hearts preserved in Somah should be viable for up to 10 days. Celsior can store the organ for 4 hours. That's an epic difference.
And one that investors are hoping to bank on. A new startup, Hibergenica, is looking to commercialize Somah for use in humans. The company is still in its very early stages. Likewise, Somah still has a ways to go. Transplants from pigs to other pigs (using Somah) will have to be performed before human clinical trials can begin. We're talking years of research before the FDA would possibly approve Somah for use in the US.
Other companies are relatively closer to augmenting the time hearts stay fresh outside the body. We've already seen how TransMedics can keep a heart beating for 12 hours inside a machine, and they are moving forward with tens of millions in funding. Somah, however, could potentially keep hearts viable for 20 times longer, and probably with fewer electrical and mechanical requirements. It will be interesting to see how these technologies ramp up in comparison to stem cell projects aimed at creating entirely new organs from a patient's own cells. Simpler forms of that concept (for windpipes) have had a series of successes recently with human patients. No matter which of these technologies is the first to achieve widespread use, the future seems ready to provide us with the means to get a new heart when we need it.
[image credit: Harvard]
[source: Technology Review, Tech Transfer (Harvard), Circulation]