Discussion
toxicity, airway neutrophilia
Consistent with previous observations, DE induced airway neutrophilia and increased number of lymphocytes and mast cells in the endobronchial mucosal biopsies 6-h post-challenge [study of a skewing towards a Th2 response [Based on the observations in in vitro cell models, DEPs have been shown to elicit a sequenced activation of redox-sensitive signalling cascades, reflecting changes in the intracellular glutathione (GSH)/glutathione disulphide (GSSG) ratio [In a previous study, Jaiswal and coworkers suggested that treatment of cells with xenobiotics and antioxidants leads to dissociation of Nrf2 and keap1. The nuclear translocated Nrf2 may then heterodimerize with c-Jun and bind to the ARE, resulting in the induction of NQO1 expression [A negative association was seen between epithelial nuclear AhR and submucosal CD3The toxicity of PM-associated PAHs is traditionally thought to be mediated by the cytosolic AhR [Schematic presentation of AhR activation and co-localization of leukocyte nuclear AhR with CD3 cells. Panel In the present study, nuclear translocation of AhR in the epithelium was negatively associated with the number of CD3The increased AhR nuclear translocation in the submucosal leukocytes, may be caused by DE-related AhR ligands, escaping the epithelial barrier and activating AhR in the submucosal leukocytes (Fig. 