Furthermore, sulforaphane can augment the phagocytosis of bacteria (such as PA and NTHI isolated from COPD patients) by alveolar macrophages from COPD patients, but the ability is absent in Nrf2 siRNA-transfected macrophages, and similar results are obtained in wild-type and Nrf2 knockout mice. Here, NFE2L2 is linked to chronic obstructive pulmonary disease.