Innate lymphoid cells promote lung-tissue homeostasis after infection with influenza virus.

Abstract

Innate lymphoid cells (ILCs), a recently identified heterogeneous cell population, are critical in orchestrating immunity and inflammation in the intestine but whether ILCs can influence immune responses or tissue homeostasis at other mucosal sites remains poorly characterized. Here we identify a population of lung-resident ILCs in mice and humans that expressed CD90, CD25, CD127 and T1-ST2. Strikingly, mouse ILCs accumulated in the lung following influenza virus infection and depletion of ILCs resulted in loss of airway epithelial integrity, decreased lung function and impaired airway remodeling. These defects could be restored by administration of the lung ILC product amphiregulin. Collectively, these results demonstrate a critical role for lung ILCs in restoring airway epithelial integrity and tissue homeostasis following influenza virus infection.