Researchers on the verge of GROWING Human Hearts

As I type, 17 human hearts are currently forming and there is much anticipation as to whether they will beat.

Being led by Dr Doris Taylor in collaboration with colleagues in Madrid at The Centre for Cardiovascular Repair – University of Minnesota. the work builds on previous successes with both rat and pig hearts using “whole organ decellularisation”. This novel technique involves washing cardiac cells out to leave only a pale fibrous matrix-“a ghost heart”. This then acts as a scaffold on which stem cells placed divide, grow, and contract causing the heart to beat. In the midst of seminars, flights and on-going research, I caught up with Dr Taylor to explore this groundbreaking venture in cardiovascular repair.

Creating organs for transplant is a subject matter often viewed with dubious sentiment – caught somewhere between science fiction and reality – but Dr Taylor tells me to “trust your crazy ideas”. A motto of hers from which “the decelluarlised ‘ghost’ heart was born”, in a search for radical ways to treat end-stage heart failure. “Nature has created some very complex and effective tools for repairing the human body. Endogenous repair, or the body’s ability to heal itself, is a powerful tool that we’re just starting to understand how to harness. I believe that it is possible to harness it, to optimize it and to begin to reverse disease and aging.”

In 1998 the team pioneered transplanting stem cells to patients post heart attack, leading to improved function. Reminiscing on publishing the work, Dr Taylor said “A member of the media asked me: ‘If it’s so simple, why someone hasn’t done it before?’ And what I realised was that no one had done it before because no one had believed it was possible.”

It became clear that whilst the nature of her work would be very simple, “we were never going to understand exactly how it worked”. Thus forming the philosophy “giving nature the tools and getting out of the way”, to illustrate largely how little they understood about what they were doing. But she pointed me to the example of willow bark-“hundreds of years after it was first used as an analgesic, we still don’t fully know how aspirin stops pain. That being said, we don’t have to understand every detail but…understand it enough to make it safe and effective.”

Work is underway on a variety of organs; lungs, kidney, liver, and pancreas to name but a few. At the center for cardiovascular repair, human liver cells grown on a rat liver matrix have been show to metabolise drugs out to thirty days, whilst pancreas studies in collaboration with the University of Wisconsin “are moving quickly”. The biggest struggle facing such work is funding I am told – currently “at historic lows with further cuts being proposed” to the National Institute of Health.

Whilst “these advances are exciting and hold great hope for future therapeutics”, it is evident they are still at the early stages of research.

“Many hurdles will have to be passed before we can perhaps use scaffolds from cadavers or pig hearts to build human hearts amongst other organs for transplantation. But what this marks “is the future of treatment of cardiovascular issues.” One that will be “a multifaceted approach involving drugs, cell therapy, matrix repair and replacement”.

This image is of rats hearts that were successfully recellularised and began to beat.