Introduction. Determination of epithelial cells ciliary beat frequency (CBF) requires the introduction of variational methods of image analysis e.g. the difference between two consecutive images (DI) or the optical flow approach (OF) by image correlation or summing displacements (1).

Aim of the study. To compare results obtained using DI versus OF.

Methods. Human bronchial epithelial cells from 1 healthy donor (NHBE) and 1 patient suffering of COPD (DHBE) were purchased from a commercial source. Epithelial cells were differentiated for 21 days in Air-Liquid Interface (ALI) cultures, then salmeterol or forskolin at 3 concentrations (0.1 or 0.3 or 1µM) were applied for 30 min basolaterally and cilia beating recorded with an inverted microscope.  Videos were recorded at 100 images/s during 5 s and analysed using Python coupled to a script designed to analyse each image stack. Variational image processing methods were used on digital video-image to extract CBF.

Results. Results are reported in the graph below using distribution of CBF.

Conclusions. CBF control values in NHBE and DHBE were in the range reported in the literature. Using the OF method, salmeterol at 1 µM, significantly increased CBF values in NHBE but not in DHBE. Using DI method, salmeterol at 1 µM has a small effect on both NHBE and DHBE. Using both methods, forskolin showed no effect on both cell types.

1. Kim W. et al. Healthcare informatics research 2011; 17: 111-119.