Fig. 2. Schematic flow of in-vitro model for acute neutrophilic asthma. Primary human bronchial/tracheal epithelial Cell: Asthma (PCS-300-011) (ATCC, Manassas, VA, USA) was cultivated. After 24 hours of culture, Tiotropium bromide was administered to the culture medium (50 pM and 50 μM). After 1 hour, LPS (10 mg/mL) was stimulated for 5 minutes. After 48 hours, the cells were harvested for analyses.

LPS = lipopolysaccharide.