Effects of pharmaceutical compounds on ciliary beating in human nasal epithelial cells: a comparative study of cell culture models.

PURPOSE: To test two in vitro human nasal epithelial cell culture systems for their ability to screen the effects of pharmaceutical compounds on ciliary beating.
METHODS: Human nasal epithelial cells were cultured as monolayer and in a sequential monolayer-suspension culture with in vitro ciliogenesis. The influence of reference cilio-stimulatory compounds (glycocholate, isoprenaline), reference cilio-inhibitory compounds (chlorocresol, diphenhydramine) and pH on ciliary beating was investigated using computerized microscope photometry.
RESULTS: Sodium glycocholate (0.5% w/v) maximally and reversibly increased CBF of the cells in both culture systems by 26 +/- 4% (monolayer) and 18 +/- 6% (suspension). Similarly, isoprenaline (10(-3) M) maximally, but irreversibly increased CBF of the cells by 14 +/-3% (monolayer) and 17 +/- 4% (suspension). Chlorocresol (0.005% w/ v) reversibly reduced the CBF of the cells by 50 +/- 6% (monolayer) and 34 +/- 4% (suspension); at a higher concentration (0.1% w/v) it resulted in instantaneous and irreversible ciliostasis. Diphenhydramine (0.1% w/v) reversibly reduced CBF in both culture systems by 45 +/- 13% (monolayer) and 69 +/- 5% (suspension); irreversible cilio-stasis occurred in less than 2 minutes in both culture systems upon cell exposure to diphenhydramine (1.0% w/v). In the monolayer culture system, CBF was stable only within the physiological pH range of 6.5-8.0; ciliary beating in the suspension culture remained stable within a pH range of 4.0-10.0.
CONCLUSIONS: Both cell culture systems are suitable for screening the effects of pharmaceutical compounds on ciliary beating. Especially the sequential monolayer-suspension culture appears to be very promising as ciliary activity can be preserved for as long as 6 months.