Effects of allergens on the expressions of IL-18, IL-18BPα and IL-18Rα in blood CD4+ Th1 cells of patients with allergic rhinitis.

Objective To investigate the effects of allergens on the expressions of IL-18, IL-18BPa and IL-18Rα protein in peripheral blood CD4⁺ Th1 cells of healthy control subjects (HC) and patients with allergic rhinitis (AR), and on the expressions of IL-18, IL-18BPa and IL-18Rα mRNA in the peripheral blood CD4⁺ T cells. Methods Blood samples were collected from patients with rhinitis for negative skin prick test (AR-), rhinitis for positive skin prick test (AR⁺) and HC. Flow cytometry was used to evaluate the effects of allergens on the expressions of IL-18, IL-18BPa and IL-18Rα protein in CD4⁺ Th1 cells. The expressions of IL-18, IL-18BPa and IL-18Rα mRNA in CD4⁺ T cells were determined by qPCR. Results Compared with HC, increased IL-18 while decreased IL-18BPa expressions in Th1 cells of AR^- and AR⁺ patients were observed, increased IL-18Rα expression in Th1 cells of AR⁺ patients was also found. Additionally, allergens induced elevated expression of IL-18Rα protein in Th1 cells of HC, and induced elevated mRNA expressions of IL-18, IL-18BPa and IL-18Rα in isolated blood CD4⁺ T cells of AR⁺ patients and HC. Conclusion Allergens may be involved in the pathogenesis of AR by inducing the expressions of IL-18 and IL-18Rα in blood CD4⁺ Th1 cells. [ABSTRACT FROM AUTHOR]