S100A7 Co-localization and Up-regulation of Filaggrin in Human Sinonasal Epithelial Cells

Objective:Filaggrin(FLG)is a protein expressed in the epidermis and involved in the maintenance of the epidermal barrier.However,the expression and localization of FLG in the upper airway remain controversial.The present study aimed to determine the significance of FLG and the effect of S100A7 on FLG expression in the upper respiratory mucosa.Methods:Human nasal epithelial cells(HNECs)were cultured and examined for FLG expression and S100A7 effects by real-time polymerase chain reaction and Western blotting.The localization and distribution of FLG were assessed using sinonasal mucosa.Results:A significant expression of FLG was detected at the mRNA and protein levels in HNECs.A moderate FLG immunoreactivity was observed in the epithelial cells,but no staining was seen in epithelial goblet cells.S100A7 increased the FLG mRNA level in HNECs in a dose-dependent manner and also up-regulated the FLG protein in a dose-dependent manner.Conclusion:This study significantly contributes to a better understanding of the role of FLG in the pathogenesis of airway inflammation from the viewpoint of the epithelial barrier function.FLG-related events in response to S100A7 protein may represent novel therapeutic targets for the treatment of upper airway inflammation.

Sodium channels in the apical membrane of human nasal epithelial cells

Objective To study the electrophysiological properties of sodium channels in the apical membrane of human nasal epithelial cells Method Nasal epithelial cells of human inferior turbinate from patients with obstructive sleep apnea syndrome were cultured in serum free medium on collagen gel coated membranes at an air liquid interface and studied by a patch clamp technique Results In cell attached patches, a typical single channel current with a conductance of 21 09?pS and reversal potential of -50 96 were recorded The permeability ratio P Na /P K was more than 5 80 In the presence of 10 4 mmol/L amiloride in the pipette, the incidence of sodium channels decreased from 26 67% to 5 13% This revealed that a population of channels were inhibited by amiloride at a dose of 10 4 mmol/L Ca 2+ at dose of 10 3 mmol/L did not influence the incidence of sodium channels There was no obvious association between voltage and the open probability of the channels Conclusions Our results indicate that most Na + channels in cell attached patches of human nasal epithelial cells are amiloride sensitive and Na + selective Only a few channels are amiloride insensitive The channels were not activated by extracellular Ca 2+ and the open probability followed a voltage independent manner

Comparison of human nasal epithelial cells grown as explant outgrowth cultures or dissociated tissue cultures in vitro

The purpose of this study was to compare cell growth characteristics,ciliated cell differentiation,and function of human nasal epithelial cells established as explant outgrowth cultures or dissociated tissue cultures.Human nasal mucosa of the uncinate process was obtained by endoscopy and epithelial cell cultures were established by explant outgrowth or dissociated tissue culture methods.Epithelial cell growth characteristics were observed by inverted phase contrast microscopy.Ciliated cell differentiation was detected byβ-tubulin IV and ZO-1 immunocytochemistry.Basal and ATP-stimulated ciliary beat frequency(CBF)was measured using a high-speed digital microscopic imaging system.Both the explant and dissociated tissue cultures established as monolayers with tight junctions and differentiated cell composition,with both types of cultures comprising ciliated and non-ciliated epithelial cells.Fibroblasts were also frequently found in explant cultures but rarely seen in dissociated tissue cultures.In both culture systems,the highest ciliated cell density appeared at 7th–10th culture day and declined with time,with the lifespan of ciliated cells ranging from 14 to 21 days.Overall,10%of the cells in explant cultures and 20%of the cells in the dissociated tissue cultures were ciliated.These two cultures demonstrated similar ciliary beat frequency values at baseline(7.78±1.99 Hz and 7.91±2.52 Hz,respectively)and reacted equivalently following stimulation with 100μM ATP.The results of this study indicate that both the explant outgrowth and dissociated tissue culture techniques are suitable for growing well-differentiated nasal ciliated and non-ciliated cells,which have growth characteristics and ciliary activity similar to those of nasal epithelial cells in vivo.