Air-Liquid Culture of Airway Basal Cells

Bronchial tissue segments from normal lung donors and explanted lungs from COPD patients were collected at the time of lung transplantation. COPD patients provided written informed consent forms to use their explanted lungs for research (IRB# 4407). Donors of normal lungs had standing consent to use their organs for organ transplant and research after their demise. The collection and use of the tissue samples were approved by University of Michigan (IRB# HUM00050876) and Temple University (IRB# 23903) institutional review boards. All methods were performed in accordance with the relevant guidelines and regulations. Patient characteristics are provided in supplementary table S1. Airway basal cells from bronchial segments were isolated and expanded in the BronchiaLife medium (Lifeline Cell Technology, Frederick, MD, USA). The basal cells at passage 1 were cultured in 12-mm transwells at an air/liquid interface to promote mucociliary differentiation, as described previously [10 (link), 19 (link)]. We seed ∼90 000 live cells·cm⁻² in a transwell, and this seeding strategy did not indicate difference in growth rate between COPD and normal cells.