Participants without a bronchodilator withhold will be scheduled to undergo a methacholine test. Those that qualify will undergo a bronchoscopy to obtain bronchoalveolar lavage and airway epithelial cells and nasal epithelial brush sampling for gene expression studies. After the procedure is done and post bronchoscopy safety standards are met, participants will be discharged from the inpatient Clinical Translational Research Center (CTRC) recovery area. The research coordinator will call the participant on the night of the procedure and on the next day to document post-procedure clinical stability.