Lung Inflammation and Fibrosis

The alveolar inflammatory reaction, important for amplifying host defenses in the lungs, is in part under the cellular control of the pulmonary alveolar macrophage, which can initiate and modulate the reaction. A chronic, poorly regulated reaction can cause tissue dysfunction including fibrosis. This historical perspective will review the efferent function of alveolar macrophages that elicits inflammation through secretion of several chemokines, examining how some of these were identified from normal macrophages, and later investigated in lung fibrosis, particularly idiopathic pulmonary fibrosis (IPF). The focus is on two chemokines: interleukin-8 (IL-8) and leukotriene B4 (LTB4).