In early July, Karolinska University Hospital issued a press release about a successful trachea transplant using synthetic tissue.  It got mainstream media coverage and it was interesting, I thought, but evolutionary and not revolutionary.  We had covered a Lancet paper on much the same thing in 2008.  But in the course of a correspondence with a media rep she noted something important; not only was this not a traditional transplant, this was not even one where an organ was decellularized and recellularized with the patient's stem cells, it was created for the patient and in just two days.

That meant no immunosuppressive drugs, at $20,000 per year, and no morbidities due to their side effects.

To me, it also meant no waiting list for a transplant.  Ever.

Forget the operation, I thought, that can excite Reuters and USA Today readers for a day.  I wanted to talk about the machine that might make it possible to get people excited about this for the next five years. 

So she put me in touch with David Green, President of Harvard Bioscience, the company that made the bioreactor which grew the new trachea. It looks simple, like a box with a scaffold.  Heck, it looks like a chicken rotisserie but E=MC^2 looks simple too. The reality is that a lot of complexity goes into a simple box that is able to make a new trachea using a patient's own stem cells. Tissue engineers have been marrying cells to matrices to regrow parts for years but this was a step beyond because no donor organ was needed - and it saved the patient's life.

Looks simple, right?  Sure, in the way 2,000 years of all science looks simple.  Credit: Harvard Bioscience

The process sounds easy enough, they made a polymer trachea and then they bathed it in stem cells and turned it once a minute.  Sounds more and more like that chicken rotisserie, right?  More like seeding your lawn at this point - though maybe an FEA mesh is a better analogy for the Science 2.0 audience, since science types don't mow the lawn - the seeded cells grew and formed into the new organ, inside and out.  After that the surgery looked routine - to you and me.  In reality the entire process was quite intricate.

Courtesy of Harvard Bioscience.  Not to be reused without their express permission.

A trachea is a milestone but there are only about 1,800 situations per year where this will help patients.  Esophageal cancer occurs 20 times as often and coronary artery bypass grafts occur a million and a half times per year.  And then there are the Big 5 in the future - solid organs like the heart, lung, liver, kidney and pancreas.  That's the future, that's the excitement.

First would need to come the esophagus on the road map to something like a lung transplant. The esophagus is 10 times as long as the trachea and is muscly, not a hollow tube.  That sort of controlled chaos growth is not yet possible, I quickly learned, but it is getting closer.

A National Geographic program on this technology.

Harvard Bioscience President David Green is not an effusive guy.  He is running a business and that business is essentially involved in saving lives, which is serious stuff.  His knowledge is comprehensive and he's dealt with so many questions about their technology he is quite casual in his responses.  He knows what you are really asking even if you phrase it the wrong way and you feel like you emerged a little smarter at the end.

Near the end of our talk I asked him, "Is this real?" and he knew immediately what I meant.  His excitement then was apparent, the kind of excitement someone who can see the near(ish) future has.

"This is real," he said. "There's been so much hype about stem cells, and controversy, and now there are people in China who say they can cure anything by injecting patients with stem cells, there were issues with deaths related to gene therapy which also cast a shadow over regenerative approaches.  There is always going to be hype.  But this is not science fiction.

"There's no medical barrier now.   Miss Castillo is alive after three years and Mr. Teklesenbet was released shortly after the surgery."

That there are only science and technology hurdles is the exciting part. That means the road is visible to the medical community and there is no longer a magical 'black box' between the world of organ transplants today and the science fiction medicine of customized organs tomorrow. 

One hurdle is that this kind of procedure is limited to a consortium of elite universities and hospitals.  The success of Teklesenbet's operation took a world-class cell culture facility, world-class materials expertise for the scaffold, world-class surgeons, a world-class post-surgical analysis team and a custom bioreactor made by a company that didn't need to sell it in order to create it for an important surgery. 

But that success even at the world-class level means the proof of concept is there for future regional hospital teams.  The actual organ took only two days to grow and it was essentially handed to the surgical team like one in a more routine transplant operation would have been.  In the future this could be done at any quality hospital, much like transplants are today.

The technological hurdles in the future are substantial but just that; hurdles and not walls.  It took two weeks to create the scaffold, for example, but experience and expertise will shorten that.  A higher set of hurdles are the requirements for complex solid organ transplants, like a kidney or a lung. Creating a new replacement lung this way, for example, not only requires a far more complicated bioreactor and scaffold, but also that no one is able to get the required number of stem cells yet.

Dr. Paolo Macchiarini, professor of regenerative surgery at the Karolinksa Institute and the surgeon behind this transplant and the one in 2008, says successful work has been done on solid organs in rodent-size animals but that research could even lead to a more optimal result than a transplant with no drugs or rejection is; self-repair of the organs.