FIGURE 1: Schematic representation of the biological processes induced or mediated by PI3Kγ in the cell types that are relevant for respiratory disease. PI3Kγ has been involved in almost all target cells shown in the figure using either isoform-selective PI3K inhibitors or genetic engineering. *Neutrophilic recruitment may be enhanced by either activation or inhibition of PI3Kγ, depending on the context. NO: Nitric Oxide; αSMA: α-smooth muscle actin; VEGF: Vascular endothelial growth factor; IL-13: Interleukin-13.