IL13 and hypersensitivity pneumonitis: Second, alveolitis with inflammatory cell infiltrates, including morphologically activated “foamy” macrophages, neutrophils and eosinophils associated with elevated pro-inflammatory cytokines such as IL-1β, KC and IL-13 in BAL, was substantially more prominent in neonatal congenital Nedd4-2−/− compared to conditional Nedd4-2−/− mice (Figure 3) [9].