Bronchial cell pyroptosis promotes Th17 proliferation and activation in vitro

<bold>Background:</bold> Human bronchial cell (BC) could be induced to pyroptosis by toluene diisocyanate (TDI), and then secrets HMGB1. The HMGB1 could promote the number and activation of Th17 cells via TLR4. In this study, we aim to investigate the relation between bronchial cell pyroptosis and Th17 cells. <bold>Methods:</bold> Primary bronchial cells and CD4+T cells were separated from health mice. The bronchial cells were induced pyroptosis by TDI. When withdrawal TDI, bronchial cells were co-cultured with CD4+T in the condition with TGF-β and IL-6. The pyroptosis cytokines (pro-caspase-1, caspase-1 p20, pro-GSDMD, cleaved-GSDMD) and Th17 factors (IL-17A, IL-17F, TLR4 and STAT3) were assessed by western blotting. Th17 number was assessed by flow cytometry. <bold>Results:</bold> The morphology of bronchial cell pyroptosis was confirmed under transmission electron microscope. The caspase-1 p20 and cleaved-GSDMD protein levels were significantly increased in TDI-induced bronchial cells. Th17 number and protein expressions of IL-17A, IL-17F, TLR4 and STAT3 were increased, when CD4+T cells induced into Th17 in the micro-environment of bronchial cell pyroptosis. <fig><object-id>erj;64/suppl_68/PA3516/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig> <bold>Conclusion:</bold> Bronchial cell pyroptosis may promote Th17 proliferation and activation in vitro.