New Airway-Hugging Immune Cells Discovered in the Lung

Scientists have discovered a previously unknown subset of immune cells residing in the lung that specifically combat viral infections. The respiratory tract is particularly susceptible to invading viral pathogens, such as influenza, or SARS-CoV-2 (the virus that causes COVID-19).

Alveolar macrophages, or AMs, are the first line of cellular defense in the airways. These immune warriors deal with incoming infectious agents by “gobbling” them up through a process known as phagocytosis. They also secrete a cocktail of inflammatory chemicals known as cytokines, to recruit other immune cells to the site of potential infection.

“I think what excites me most about our findings is the fact that we have identified a unique subset of the macrophage population (a critical cell type of the innate immune system) that we know very little about.”

Scientists from Columbia University Medical Center found a distinct subset of AMs: nerve and airway associated macrophages, or NAMs. From their studies in mice, the group observed that this particular group of cells played a central role in dampening inflammatory responses during viral infections, in order to prevent damage to the…