Researchers have successfully transplanted a bioengineered lung into a pig, according to a paper published last week in the journal Science Translational Medicine. This newfound success by researchers marks an important step towards paving the way for the same procedure in humans, which, given the scarcity of lungs for transplants, would be a pivotal development. The team says that transplants of lab-grown lungs for human patients could be possible within a decade. Their research was detailed in a BBC News report Friday.
“People wait for a long time on a transplant list before they are able to receive a donated lung,” according to one of the study’s coauthors, Professor Joan Nichols.
The researchers, at the University of Texas Medical Branch (UTMB) in Galveston, began by creating a structure that would allow the lung tissue to grow around it. They then added cells taken from the same pig that was set to receive the transplant, ensuring that its immune system would not reject the lung.
The “scaffolding” was made by using sugar and detergent to eliminate the cells and blood vessels of a lung from a second pig, leaving behind a protein structure around which the new lung could form. Inside a bioreactor, which aids in the growth of biological tissue, the team used stem cells and growth factors to spark the development of blood vessels and different types of cells.
Folowing the procedure, they ensured the lungs were continuing to develop properly after the transplant, using MRI and CT scanning.
By the end of the two-month study, the lung was, crucially, not rejected by the pig’s immune system. Furthermore, a crucial bacteria population developed in the lungs following the procedure.
However, the time period was too short to allow the researchers to properly assess how much oxygen was provided by the lab-grown lung.
“The lungs weren’t really mature enough at two months,” according to Nichols. However, the pig’s blood was still fully saturated with oxygen after the transplant.
Past efforts toward such a procedure have failed in small animals, which suffered from oedema, an accumulation of fluid, as a result of problems with the blood vessels in the transplanted lung.
Discussing the future possibilities in human lung transplants, Nichols explained:
“We could take cells from people and produce an organ tissue matched to them, with no immuno-suppression needed.”
According to another coauthor, Professor Joaquin Cortiella, this progress could eventually improve both the quality and quantity of successful lung transplants.
“We don’t fit donated lungs very well to how big an individual is… bioengineered lungs can be made at any time, so patients don’t have to wait until an organ is available,” he said. “I would say somewhere around 5-10 years you will see someone actually get a bioengineered lung.”