Creating Lungs “From Scratch”

6b grey

Erica Comber, a PhD student in Carnegie Mellon University’s (CMU’s) Department of Biomedical Engineering (BME), and her colleagues in Carnegie Mellon University’s Bioengineered Organs Initiative, are working to help people with lung disease by making them new ones.

Ms. Comber and her adviser Keith Cook, PhD, professor of biomedical engineering at CMU and an affiliated faculty member at the McGowan Institute for Regenerative Medicine, recently outlined several different approaches to creating human lungs from scratch in a first-of-its-kind paper.

“There’s a huge divergence of approaches in this field, and no one approach is necessarily more valid than another,” Ms. Comber said. “It’s about using different techniques to try to accomplish the same goal and then learning from each other.”

By identifying important parameters to consider and describing different approaches, the paper, published in Translational Research, will act as a guide to future researchers looking to create human organs de novo, or “from scratch.”

Approaches span from using existing biological organs as a starting point — by removing cells from existing organs and recellularizing them with the patient’s own cells — to generating completely artificial organs.

Ms. Comber’s work is a hybrid of those two approaches. Using natural materials such as collagen type 1, Ms. Comber makes artificial lungs that can be housed within the chest and designed in geometries that optimize how much oxygen and carbon dioxide can be cycled in and out of the circulatory system.

Existing artificial lungs are largely stopgap measures, and a plethora of complications can arise from their use. The average duration of use is about a week, and a patient’s chance of surviving the therapy shrinks the longer they’ve been supported. Artificial lungs made from polymer also can cause blood to form clots on the surface, which is why they fail and must be frequently replaced. Drugs used to slow blood clots also can cause bleeding, and each time artificial lungs are replaced, the patient can be exposed to a risk of infection.

De novo lung biofabrication could be the key to solving these issues. By designing artificial lungs that can be permanently attached to the circulatory system, and that can be created in geometries that approximate lung geometries but optimize for gas exchange, researchers could remedy the blood clotting and bleeding risk associated with existing artificial lungs.

“We have a long way to go, but we expect to see these de novo organs commercially available in our lifetime,” Ms. Comber said.

Ms. Comber is co-advised by Dr. Cook and Adam Feinberg, PhD, associate professor of biomedical engineering and materials science and engineering at CMU and an affiliated faculty member at the McGowan Institute of Regenerative Medicine.

Illustration: Carnegie Mellon University.