Harvard, Yale researchers make strides in lung regeneration

Researchers have created a device about the size of an eraser that mimics a breathing human lung. The device is made using human lung and blood vessel cells and allows the scientists to see the inner-working of a human lung without having to conduct an invasive procedure, according to scientists from the Wyss Institute for Biologically Inspired Engineering at Harvard University, Harvard Medical School and Children's Hospital Boston.

The lung-on-a-microchip may also help accelerate pharmaceutical development by reducing the reliance on current models, in which testing a single substance can cost more than $2 million. "The ability of the lung-on-a-chip device to predict absorption of airborne nanoparticles and mimic the inflammatory response triggered by microbial pathogens provides proof-of-principle for the concept that organs-on-chips could replace many animal studies in the future," says Donald Ingber, senior author on the study and founding director of Harvard's Wyss Institute, in a statement.

Meanwhile, a Yale University-led team of scientists reports it has achieved an important first step in regenerating fully functional lung tissue that can exchange gas. The team wanted to see if it was possible to successfully implant tissue-engineered lungs that could help exchange oxygen and carbon dioxide. They removed existing cellular components from adult rat lungs, preserving the extracellular matrix and hierarchical branching structures of the airways and vascular system to use later as scaffolds for the growth of new lung cells.

They then cultured a combination of lung-specific cells on the extracellular matrix. Under the fetal-like conditions of the bioreactor, the cells repopulated the decellularized matrix with functional lung cells. When implanted into rats for short intervals of time, the engineered lungs exchanged oxygen and carbon dioxide similarly to natural lungs.

This work is not the first successful effort to build functional tissue, as the Boston Globe notes. But the two new studies are significant milestones in the quest to build a functional organ in the lab. The Wyss paper appears in the June 25 issue of Science, while the Yale report appears in the June 24 issue of Science Express.

- see the Wyss Institute release
- check out the Yale release
- read the Boston Globe's report