Role of interleukins and transforming growth factor-β in chronic rhinosinusitis and nasal polyposis

Objectives: To determine the role of interleukin (IL)-4, IL-4 receptor (R), IL-6, IL-8, IL-11, and transforming growth factor (TGF)-beta in chronic rhinosinusitis (CRS) and chronic rhinosinusitis with nasal polyposis (CRS/NP). Methods: Sinus tissue from patients undergoing endoscopic sinus surgery for CRS and CRS/NP was collected. Sinus tissue was then analyzed using reverse-transcription polymerase chain reaction (RT-PCR) to detect transcription of IL-4R, IL-6, IL-8, and IL-11. Sinus tissue samples were also cultured in vitro, treated with IL-4 for 24 hours, and real-time PCR was used to quantify the transcription of TGF-beta. Results: Twenty patients were evaluated, 9 with CRS/NP and 11 with CRS alone. The mean age was 43 (20-74) years, with 13 females and 7 males. IL-4R, IL-6, IL-8, and IL-11 were identified by RT-PCR in all 20 patients. The transcription of TGF-beta was found to be 3.2 times greater in patients with CRS/NP than in patients with CRS alone (P = .047). Conclusion: IL-6, IL-8, and IL-11 are nonspecific markers of sinus inflammation being transcribed in patients with CRS and patients with CRS/NP. However, patients with CRS/NP demonstrate increased transcription of TGF-beta in response to IL-4 treatment, suggesting an IL-4 mediated mechanism for stromal proliferation in the formation of nasal polyposis.