HDM-induced Atg5 Mediates TSLP Expressing to Disrupt Epithelial Barrier

Abstract Background: Asthma is a complex and heterogeneous disease. Autophagy, process of self-protection in cells, is an intracellular process when cells are being attacked by certain stress. Our team focused upon the disruption of airways epithelial barrier in asthma, and we interested in whether autophagy played a key role in asthma. Methods: 400U HDM was used to treat HBECs and established asthmatic mice model. Western blotting, RT-PCR and immunofluorescence were mainly used to detect autophagy process in vivo and in vitro. One way ANOVA and Mann Whitney test were used for statistic. Results: After treated with HDM, expression of LC3ab increased in vivo and in vitro. Using Rapamycin, 3-MA and Chloroquine to treat HBECs, then we surprisingly found that HDM disrupts epithelial barrier through incomplete autophagy. To find out the connection between asthma and autophagy, we chose known autophagy related genes to determine the association between autophagy and disruption of airway epithelial barrier. Atg5 and atg12 were chosen because these two genes varied upon the time dependent manner. Knocked down the expression of atg5 or atg12 by siRNA, the expression of TSLP, which can induce the disruption of airway epithelial barrier, remarkably reduced. Conclusions: These results demonstrated that HDM induced inflammatory in airway epithelium through autophagy, and then knocked down autophagy related genes alleviated the inflammatory in HBECs.