In the present study, we showed that primary bronchial epithelial cells from COPD and non-COPD patients respond to diesel exhaust (DE) exposure by an increased expression of the oxidative stress response gene HMOX1 and of CXCL/IL-8, and activation of the integrated stress response (ISR), while no effect on barrier function or cell death was found in both groups. This evidence concerns the gene HMOX1 and chronic obstructive pulmonary disease.