Insulin-Like Growth Factor-1 Signaling in Lung Development and Inflammatory Lung Diseases

Figure 3

Cellular responses activated by IGF-1 in asthmatic airway inflammation. IGF-1 reduces AECs (airway epithelial cells) phagocytosis of dust mite and induces its hypersecretion, migration, and epithelial-mesenchymal transition (EMT). IGF-1 activates the proliferation of ASM (airway smooth muscle cell) and induces its contraction and hyperplasia. IGF-1 enhances blood vessel permeability. IGF-1 induces the degranulation of mast cell and basophil and release of histamine and leukotriene, activates the migration of basophils, and inhibits apoptosis. IGF-1 induces FCεRII expression and production of IgE and IgG4 in B cells. IGF-1 activates the proliferation of Treg (regulatory T cells) and activates eosinophils and macrophages. IGF-1 activates fibroblasts and myofibroblasts which generates extracellular matrix (ECM). IGF-1 activates GM-CSF, VEGF, LTD4, IL-4, IL-5, IL-13, IL-25, IL-33, IL-17A, and vice versa. BM: basal membrane.