OP-B induced pyroptosis of A549/DDP cells by activating Caspase-1/GSDMD pathway. A-B. mRNA (pro-Caspase-1, Caspase-1, IL-1β, GSDMD, GSDMD-N and NLRP3) expression determined by qRT-PCR analysis in A549 and A549/DDP cells treated with different doses of OP-B. C. Protein (Caspase-1, GSDMD, GSDMD-N, NLRP3 and β-actin) expression determined by western blot analysis in A549 and A549/DDP cells treated with different concentrations of OP-B. D. Protein (Caspase-1, GSDMD, GSDMD-N and β-actin) expression determined by western blot analysis in A549 and A549/DDP cells treated with the inhibitor of VX765.E-F. Four kinds of protein expression level in A549 and A549/DDP cells treated with different concentrations of OP-B. G. Three kinds of protein expression level in A549 (a) and A549/DDP (b) cells treated with inhibitor of VX765. H. Representative images showing haematoxylin and eosin staining of lung samples from the different groups. I. GSDMD-N expression in the tissue of lungs of the different groups. The bars and error bars indicate the mean ± SD. *p < 0.05, **p < 0.01, ***p < 0.005, ****p < 0.001