Increased expression of pigment epithelium-derived factor in allergic rhinitis

Objectives: To investigate the expression of messenger RNA (mRNA) of the gene for pigment epithelium-derived factor (PEDF) (OMIM *172860) and PEDF protein and to localize the PEDF protein in the nasal mucosa of patients with allergic rhinitis and of control subjects. Design: Investigation of PEDF mRNA and PEDF protein expression in the nasal mucosa using reverse transcription-polymerase chain reaction, Western blotting, and immunohistochemical staining. Participants: We used inferior turbinate mucosal samples from 10 patients with allergic rhinitis and 10 matched healthy control subjects. Interventions: We extracted PEDF mRNA from the inferior turbinate mucosa samples and performed reverse transcription-polymerase chain reaction analysis. We used Western blotting to analyze differences in expression levels of PEDF protein between patients with allergic rhinitis and healthy controls, and the PEDF protein was localized immunohistochemically. Results: The expression levels of PEDF mRNA and PEDF protein in the nasal mucosa were significantly increased in patients with allergic rhinitis compared with those in nonallergic controls. The PEDF protein was expressed in the epithelium and submucosal glands. Conclusions: We found that PEDF protein is expressed in the human nasal mucosa, and its expression is increased in allergic rhinitis. These results suggest a possible contribution of PEDF to the chronic inflammation of the nasal mucosa in allergic rhinitis.