Anti-IL-5 immunomodulates the effect of Staphylococcus aureus enterotoxin on T cell response in nasal polyps

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a T helper-2 (Th2) inflammatory disease with considerable impact on the quality of life. Staphylococcus aureus enterotoxins (SAEs) can induce and/or amplify inflammation. In this study, we investigated the immunomodulatory effect of SAEs on cytokine production by T cell obtained from nasal polyps (NPs) and examined whether neutralizing interleukin 5 (IL-5) can reverse the immunological effect mediated by those toxins.

NP tissues were obtained from all patients who underwent endoscopic sinus surgery for CRSwNP. NP cells were isolated and stimulated in vitro with SAEs in the presence or absence of anti-IL-5. Flow cytometry (FACS) analyses were performed to measure specific T lymphocyte cytokine production.

Seventeen patients (mean age 48 years) were enrolled. SAEs significantly increased the IL-4, IL-5 (Th2) and interferon (INF)-γ (Th1) cytokines released from T lymphocytes of NPs. The addition of anti-IL-5 suppressed IL-4 and INF-γ release, which was most evident on NP tissue with high basal levels of IL-5.

Neutralizing IL-5 is a potential therapeutic modality in patients with NPs, the effect of which is dependent on IL-5 levels.