Background: The study of small airway diseases such as post-transplant bronchiolitis obliterans syndrome (BOS) is hampered by the difficulty in assessing peripheral airway function either physiologically or directly. Our aims were to develop robust methods for sampling small airway epithelial cells (SAEC) and to establish submerged SAEC cultures for downstream experimentation.
Methods: SAEC were obtained at 62 post-transplant bronchoscopies in 26 patients using radiologically guided bronchial brushings. Submerged cell cultures were established and SAEC lineage was confirmed using expression of clara cell secretory protein (CCSP).
Results: The cell yield for SAEC (0.956 +/- 0.063 x 106) was lower than for large airway cells (1.306 +/- 0.077 x 106) but did not significantly impact on the culture establishment rate (79.0 +/- 5.2% vs. 83.8 +/- 4.7% p = 0.49). The presence of BOS significantly compromised culture success (independent of cell yield) for SAEC (odds ratio (95%CI) 0.067 (0.01-0.40)) but not LAEC (0.3 (0.05-1.9)). Established cultures were successfully passaged and expanded.
Conclusion: Primary SAEC can be successfully obtained from human lung transplant recipients and maintained in culture for downstream experimentation. This technique will facilitate the development of primary in vitro models for BOS and other diseases with a small airway component such as asthma, cystic fibrosis and COPD.