Effect of vaping on mucociliary activity in nasal epithelial cell cultures of adolescents

E-cigarette use (“vaping”) is increasingly popular amongst adolescents, but we know little about health effects in this group, especially on the mucociliary activity. We thus investigated associations between vaping and ciliary beating frequency (CBF) and mucociliary transport (MCT) in air-liquid interface nasal epithelial cells (NECs) of vaping (≥weekly), vaping&smoking (both ≥ weekly, mixed users) and controls (<monthly vaping/smoking). CBF and MCT was assessed 24h after rhinovirus (RV-16) infection (CBF also at baseline) using an inverted transmission light microscope and the Cilialyzer software. We applied multivariable adjusted models accounting for sex, age, education, exposure to second-hand smoke and air pollution, and atopic disease. 60 adolescents were brushed nasally (mean age of 18a, range of 15-22a, 51% female). NECs of 47 participants grew successfully and more successfully in controls (89%, N=27) compared to vaping (72%, N=25) and mixed users (67%, N=6). At baseline, median CBF did not differ between groups (vaping 12.2Hz [95% CI of 10.8-12.7], mixed use 12.4Hz [9.5-17.3], control 11.3Hz [10.1-12.5]). RV infection increased CBF in vaping (14.4Hz [12.1-16.7]) and mixed users (13.6Hz [9.7-23.5]), but not in controls (11.0Hz [9.7-12.0]). MCT speed in vaping NECs was lower than in controls (median speed of 5.7μm/s [0-15.0] vs 18.6μm/s [9.9-27.3]). Multivariable adjusted log-transformed median MCT speed was similar in vaping and controls (coefficient -0.4, 95% CI -2.3-1.5, p=0.60). We found no effect of RV infection on MCT. In conclusion, vaping could affect MCT and CBF after viral infection. However, these results need to be further investigated for potential confounding factors.