The influence of the nasal brushing samples storage conditions on ciliary function

Background Primary ciliary dyskinesia (PCD) is an inherited otosinopulmonary ciliopathy in which respiratory cilia are stationary or dyskinetic. Digital high speed videomicroscopy (DHSV) is highly sensitive and specific for PCD diagnosis, but lacks standardization, particularly about the conditions for the storage of ciliated epithelial samples before ciliary functional analysis (CFA). Indeed, storage temperature and duration may impact ciliary function, but this has never been extensively studied. We aimed to evaluate the stability of ciliary function over time when nasal brushing samples are conserved either in the fridge (4 °C)or at room temperature (22 °C). Methodology Ciliated epithelial samples were obtained by brushing nasal from 9 healthy subjects. These samples were divided equally and conserved either at 4 °C or at 22 °C. Beating cilia were recorded using DHSV at 37 °C immediately, 3 hours and then 9 hours after sampling. CFA was assessed by ciliary beat frequency (CBF) and the % of normal ciliary beat pattern (CBP). Results There was no significant difference in CFA over time after sampling, regardless of the sample storage temperature ( Table 1 ). Conclusion This pilot study suggests that stability of CFA may be preserved during 9 hours after sampling, whatever if the sample is conserved at 4 °C or at 22 °C. Larger studies are needed to confirm these preliminary results notably in pathological conditions.