Effects of ozone on the nasal mucosa (epithelial cells)

Ozone is a significant public health concern worldwide. Despite increasing evidence for the role of the bronchial epithelial cells in the generation of proinflammatory cytokines there is little information on the biological relevance of ozone induced release of cytokines in nasal airway inflammation. We have investigated the effect of ozone on the nasal mucosa using immunohistochemical staining of nasal biopsies taken 6h after exposure to either 400 ppb ozone or filtered. We found that ozone significantly increases the number of neutrophils in the epithelium (p=0.03), and expression of NF-kB (p<0.03), TNF-a (p<0.05), IL-1b (p<0.03), IL-8 (p<0.007), IL-6 (p<0.02), GM-CSF (p<0.02) and ICAM-1 (p <0.01) in the epithelial cells 6h after exposure. Furthermore, we found a significant correlations between IL-8 expression and number of neutrophils (r=0.85, p< 0.002) and NF-kB and TNF-a expression (r=0.77, p<0.009) in the epithelium. These results suggest that ozone-induced inflammation of the nasal mucosa may be a consequence of increased synthesis and release of epithelial cell-derived cytokines and adhesion molecules which influence the activity of inflammatory cells.