Woodsmoke Particulate + Prednisone

Inclusion Criteria: * Age 18-45 years, inclusive, of both genders * Negative pregnancy test for females who are not s/p hysterectomy with oophorectomy * No history of episodic wheezing, chest tightness, or shortness of breath consistent with asthma, or physician-diagnosed asthma. * Forced expiratory volume at one second (FEV1) of at least 80% of predicted and FEV1/ forced vital capacity (FVC) ≥0.70. * Oxygen saturation of ≥93% * Ability to provide an induced sputum sample. * Subject must demonstrate a ≥10% increase in sputum %PMNs 6 hours following inhaled WSP exposure, when compared to baseline sputum (to be completed in a separate protocol # 15-1775). * Proof of vaccination to COVID-19. Exclusion Criteria: Clinical contraindications: * Any chronic medical condition considered by the PI as a contraindication to the exposure study including significant cardiovascular disease, diabetes, chronic renal disease, chronic thyroid disease, history of chronic infections/immunodeficiency. * Viral upper respiratory tract infection within 4 weeks of challenge. * Any acute infection requiring antibiotics within 4 weeks of exposure or fever of unknown origin within 4 weeks of challenge. * Abnormal physical findings at the baseline visit, including but not limited to abnormalities on auscultation, temperature of 37.8° C, Systolic BP \> 150mm Hg or \< 85 mm Hg; or Diastolic BP \> 90 mm Hg or \< 50 mm Hg, or pulse oximetry saturation reading less than 93%. * Physician diagnosis of asthma…