 In the United States, a variety of farming operations can generate significant amounts of dust. Chronic organic dust exposure to workers in this industry can result in several respiratory health conditions including chronic bronchitis, chronic obstructive pulmonary disease COPD, and exacerbations of asthma. Organic dust is a complex mixture containing particulate matter and microbial-associated components from gram positive and gram negative bacteria. Airway macrophages are key innate immune cells that are rapidly activated by exposure to inhaled toxins and organic dust. 