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Background The polymorphisms of human GSDMB gene on chromosome 17 have been found to associate asthma or asthma traits worldwide. GSDMB is expressed exclusively in the epithelium in a highly tissue-specific manner and regulates inflammatory response through pryoptosis. We investigate whether GSDMB regulates epithelial to mesenchymal transition (EMT) in human airway epithelial cells.Methods GSDMB knockout cells were generated by applying CRISPR/Cas9 techniques. GSDMB overexpression plasmids were used to generate overexpression model in HBEC3-KT cells. Cells were stimulated by HMGB-1 (100ng/ml) over 24-hours and α-SMA expression levels were examined by fluorescent staining and western blotting. Cells were also treated with TGF-β1 (5ng/ml) for 1, 3, and 5 days. Transcript levels of α-SMA, e-cadherin, tenascin C, fibronectin, collagen I and vimentin were quantified by qPCR. IL-6 and IL-8 levels in the supernatant were measured using ELISA.Results Upon HMGB-1 stimulation, the expression of α-SMA in HBEC3-KT wild type cells increased, indicating a successful stimulation of HMGB-1 treatment in the cells. GSDMB knockout epithelial cells had minimal expression of α-SMA without treatment and remained unchanged post HMGB-1 treatment. Western blotting confirmed the different expression levels of α-SMA in the wildtype cells and GSDMB knockout cells. In contrast, α-SMA expression levels of GSDMB overexpression cells increased after HMGB-1 treatment. With TGF-β1 treatment, α-SMA levels were significantly decreased at 5 days in GSDMB knockout cells. Collagen I was significantly increased in GSDMB knockout cells. In GSDMB overexpressed cells, tenascin and fibronectin decreased after 5 days. IL-8 levels were significantly increased in GSDMB knockout cells after TGF-β1 stimulation.Conclusions GSDMB regulates EMT in human epithelial cells by regulating collagen I, tenascin, and fibronectin levels. Further research will focus on the mechanism of GSDMB in EMT and the results will bring new insight into the new targets for treatments of fibrotic lung diseases.