To identify whether AQP4 serves an essential function in the anti-COPD inflammatory immune-related role of ISOF, treatment with TGN20 largely exempted CSE-induced increase in IL1 secretion (Fig. 7A) and elevated expression of SPP1 and PIK3C3 through AQP4 inactivation (Fig. 7B–C). This evidence concerns the gene SPP1 and chronic obstructive pulmonary disease.