Role of group 2 innate lymphocytes in aspirin-exacerbated respiratory disease pathogenesis.

Aspirin-exacerbated respiratory disease (AERD) is characterized by chronic eosinophilic nasal polyps, asthma, and airway reactions upon cyclooxygenase (COX) 1 inhibition. AERD is present in up to 7% of adult patients with asthma and the underlying pathogenesis remains largely elusive but prostaglandin D2, cysteinyl leukotrienes, mast cells, and type 2 cytokines are thought to contribute. A wealth of studies have recently implicated group 2 innate lymphoid cells (ILC2), a novel lineage-negative lymphocyte population that produces type 2 cytokines, in human allergic disease pathogenesis. Importantly, our recent work identified that ILC2s are recruited to the nasal mucosa of patients on AERD after COX-1 inhibitor administration. Here, we review the potential impact of ILC2s in the development and propagation of type 2 inflammation in AERD.