Abstract: Objective To explore the effects of SO₂ derivatives on MUC5AC and IL-13 gene expressions in the human bronchial epithelial cells(BEP2D).Methods Using BEP2D cells,the mRNA and protein levels of MUC5AC and IL-13 gene at different concentrations of SO₂ derivatives(0.000 1,0.001,0.1,1 mmol/L)were measured by real-time RT-PCR technology and immunocytochemistry method,respectively.Results Different concentrations of SO₂ derivatives exposure (0.000 1,0.001,0.01,0.1,1 mmol/L)amd different post-exposure time(0.1 mmol/L SO₂ derivatives)at 0,5,1,4 and 24 h increased mRNA expressions of MUC5AC and IL-13 in BEP2D cells compared with the control.Meanwhile,MUC5AC and IL-13 protein levels in BEP2D cells were increased at different concentrations of SO₂ derivatives exposure and different post-exposure time,peaking in 4 h post-exposure and increasing in 24 h post-exposure compared with the control.Conclusion SO₂ derivatives exposure could increase the expressions of MUC5AC and IL-13 genes on the transcription and translation levels in BEP2D cells,suggesting it might be one of the possible reasons that SO₂ pollution aggravates asthma disease.