As a bioreactor bubbles and whirls a pair of living lungs slowly takes shape. Is this a scene from Shelly’s Frankenstein? No. Instead it is an everyday occurrence in a laboratory at the University of Texas Medical Branch (UTMB) Galveston National Laboratory. The star of this “lung show” is a little pig named “Harry.” Little Harry has the distinction of being the first patient to be surgically implanted with a laboratory-built lung, and both the doctor and patient are doing just fine.
Dr. Joan Nichols of UTMB’s Galveston National Laboratory put it this way: “We build lungs here.” Nichols continued: “That’s pretty much what it’s become in the last six months or so, is a little factory to build lungs.”
The lung is a uniquely sculpted organ. Therefore, UTMB medical researchers required a pattern or scaffold upon which they could build lungs. They began with lungs acquired from dead animals and humans and spent more than a year perfecting protocols to isolate the lungs without damaging them and then remove all the cells. After the decellularization process, Nichols and her group were left with nothing but the elastic protein structure that serves as the skeleton of the lung. These lung skeletons were then incubated in a bioreactor that constant bathes the lung tissue in fresh culture medium and oxygen with lung cells extracted from living creatures. The lungs cells adhered to the lung skeleton and grew until they thoroughly covered it to create a new pair of lungs.
Dr. Joaquin Cortiella, the director of UTMB’s Laboratory of Regenerative and Nano Medicine, likened this entire process to engineering a building: “You basically have a scaffold and then you build on top of that to create the building.”
Nichols and her colleagues have used this procedure to create both animal and human lungs. A freshly minted set of pig lungs were transplanted into Harry the pig. Harry’s healthy recovery from lung transplantation surgery indicates that this procedure experiment and potentially opens up the prospect of implanting new laboratory-built lungs into people.
“It’s the first time it’s ever been done, where we’ve taken a lung and it’s inside of the lung cavity of this pig,” Cortiella said.
Bioengineered lungs could vastly expand the number of organs available for those patients who require transplants, and this is especially the case in children, according to Cortiella. Cortiella’s experience in pediatric medicine is his main motivation for taking on this research project; he sometimes had to watch babies die from lung ailments.
“I also have lung disease,” Cortiella said. “I have pulmonary fibrosis. Breathing is a difficult thing for me at times. And so, for me, I appreciate the fact that there are not enough lungs out there to give to everybody who needs them.
“And so, if we develop something that can actually be tailor-made for somebody – or at least, have something available that we can transplant into people that are on the waiting list – the less people will die waiting for them,” he said.
Harry the pig is doing well, but in order to get a fuller picture of how well the bioengineered lung interacted with the rest of the Harry’s body, he will have to be euthanized for more detailed tissue examinations.
Previously, research groups have attempted to use synthetic materials instead of lung skeletons derived from living lungs. Unfortunately, none of the synthetic materials that were tried provided adequate structural support to make a living lung. Nichols thinks that doctors may eventually be able to make replacement organs with 3-D printers.
“Someday?” she said. “Someday, we are going to use these techniques to bio-engineer organs for people that need them.”