At a Glance

Researchers used advanced tissue chip technology to learn how the physical forces of breathing help boost immunity in lung tissue.
The findings give insight into strategies to suppress the life-threatening lung inflammation triggered by viruses like influenza and SARS-CoV-2.

The COVID-19 pandemic highlighted the need for better experimental models of the lung. Such models are needed to understand disease processes, test existing drugs, and develop new therapies. Lung tissue is exposed to mechanical stress during breathing. These motions are known to affect lung development and function. However, most lung models lack the ability to control breathing movement to study its role in lung diseases.

To address this challenge, a research team led by Dr. Donald Ingber from the Wyss Institute at Harvard University developed the lung alveolus chip, named for the alveoli—the tiny sacs deep in the lung that perform gas exchange. About the size of a memory stick, the chip can support the many cell types in human lung tissue. The cells that line the lung surface grow above a thin, porous membrane. Beneath the membrane grow lung blood vessel cells fed by a continuous flow of liquid. The entire chamber can be stretched and relaxed in cycles to mimic the effects of breathing.

In past work, the team showed that a lung airway chip could be used to mimic viral infection in the human upper airway and quickly identify candidate antiviral drugs. In their new study, they used lung alveolus chips to study how breathing motions affect infection deep in the lung by influenza virus. They used the H3N2 strain, a leading cause of lung infections, hospitalizations, and deaths.

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