One of the biggest challenges that medical professionals face today is not the ability to replace a human organ, but rather the inability to get what they need when they need it. Today’s medical technology might seem magical to those who lived as recently as 100 years ago, but too often it falls short simply due to a lack of supply. The concept of transplanting an organ from one animal to another is a big deal in the scientific community, because it would make for a virtually limitless supply of donor organs. Humans would never have to die again (from a missed organ donation anyways) if they could just transplant a similar-sized heart from an animal instead. In a recent news release from the NHLBI (National Heart, Lung, and Blood Institute), a successful cross species heart transplant may be available sooner rather than later.
In a record-breaking experiment led by Muhammad Mohiuddin, M.D., of the NHLBI, scientists were able to successfully implant a pig heart into a living baboon and were able to keep it alive for over two years. More specifically, they worked with five living baboons and were able to successfully transplant five pig hearts that lasted for an average of 945 days and completely shattered previous records. In practice, the surgeons worked to place the hearts within the existing baboon circulatory system without removing the original. In this way, the baboon still had its own heart pumping blood, but this does not discount the results of this study.
The biggest challenge with any cross species heart transplant is compatibility. Namely, it is with making sure the recipient body doesn’t actually eat up the new organ because it views it as a foreign invader. The reason this study is so significant is that this new average of 945 completely destroys previous records and shows there is real progress being made in the immune-suppressing drugs they use during the transfer. Of course, the scientists also genetically engineered the pigs to have more in common with baboons, so the hearts were already better-suited to begin with. Still, if they have the ability to genetically alter the pigs and the ability to perfect the drugs even more, it could, theoretically, result in a heart that lasts a lifetime rather than just a few years.
While the reality is that a human transplant may be a long way off, this is inevitably the end-game that scientists are working towards. Still, an organ lasting for two years still leaves a lot to be desired if human subjects are to ever be tested. More than this, the big challenge is that just because a drug works to help this genetically engineered pig heart transplant to a baboon, it does not mean engineering a pig to be compatible with humans will be as easy. Not to mention, cost is still a major factor and until these organs can be made cost-effective for the researchers, they aren’t likely to arrive at human trials.
Despite all of these hurdles, this is certainly an accomplishment to pay attention to and could mean a brighter future for anyone in need of an organ transplant down the road.