Fig. 11.

Alternaria (Alt) alkaline serine protease (AASP) promotes β-arrestin-2-dependent recruitment of eosinophils and lymphocytes to the airways. Two doses of AASP were administered intranasally to wild-type (WT) or β-arrestin-2^−/− mice (n ≥ 3). Negative controls (saline) and positive controls (Alt) were included. Bronchioalveolar lavage fluid (BALF) was collected and differential counts performed. Quantification of cell types in WT mice. A: AASP exposure elicited airway inflammation of all cell types, with the exception of neutrophils. B–E: direct comparison between WT and β-arrestin-2^−/− mice of eosinophil (B), lymphocyte (C), neutrophil (D), and macrophage (E) recruitment following exposure of high and low doses of AASP. Both eosinophil and lymphocyte recruitment require β-arrestin-2 expression. P ≤ 0.05, *significant differences between bracketed experiments; #significant differences from saline control.