In Vitro Effect of Combined Hypertonic Saline and Salbutamol on Ciliary Beat Frequency of Human Nasal Epithelial Cells

Inhalation of hypertonic saline is standard of care in patients with cystic fibrosis and primary ciliary dyskinesia. However, it is unclear if adding salbutamol has further benefits. We assessed this by measuring the ciliary beat frequency (CBF) in human nasal epithelial cell (NECs) cultures. NECs obtained from six healthy, non-smoking persons were cultured at the air-liquid-interface. We nebulised ciliated NECs with 0.9% isotonic saline (control), 6% hypertonic saline, 0.06% salbutamol and a combination of the latter two. Main outcome was change in CBF over 72h. The nebulisation of hypertonic saline increased CBF within 4h and its effect lasted for 72h (see table). Salbutamol and isotonic saline increased CBF within 30min, but their effect almost completely subsided after 24h. The combination of hypertonic saline and salbutamol resulted in a rapid and long lasting increase of CBF. Isotonic saline, hypertonic saline and salbutamol all increase the CBF of NECs in vitro but differ in the dynamics of onset and duration of action. Adding salbutamol to hypertonic saline leads to a fast and long-lasting CBF increase that differs to hypertonic saline alone. This helps to understand mechanisms behind the beneficial effects of a combined therapy.