@ChaunceyGardner 1/10. Several clinical trials have shown that the mean nasal mucociliary clearance is negatively and significantly affected by cigarette smoking (PMIDs: 24669080, 3787531, 23615315,

2/10. Ciliary beat frequency is also significantly affected by smoking habit. A reduced nasal ciliary beat frequency was observed among smoking individuals in a cohort study performed in a British urban population (PMID: 9669071).

3/10. In vitro, using human 3D epithelial cultures, cigarette smoke affects the cilia beat frequency in nasal and bronchial tissue cultures (PMIDs: 33220401, 30090531). In vivo, smoke exposure also affects cilia beat frequency in mice (PMID: 20042711).

4/10. Given the consistency of these observations, and the dose response (e.g. PMID: 23615315), these mucociliary clearance-related endpoints are translational between human clinical, human in vitro and in vivo animal studies.

5/10. Smoking cessation leads to an improvement of mucociliary clearance (PMIDs: 21545372, 24863424, https://t.co/BmFu2AnabI). Hence, the cilia function recovers over time following smoking cessation (as you wrote in your Tweet).