Background: Asthma is a heterogeneous airway inflammatory disease. IL-36 cytokines subfamily is known as a member of the IL-1 family, which consists of three agonists (IL-36?, IL-36?, and IL-36?) and two antagonists (IL-36 receptor ? and IL-38). The IL-36 subfamily has been reported to be involved in the pathogenesis of various diseases, such as the upper airway diseases, COPD, and the skin and general autoimmune diseases. However, contribution of the IL-36 subfamily on the pathophysiology of asthma remains to be elucidated.
Objectives: The objective of this study was to determine whether plasma concentrations of the IL-36 subfamily were associated with clinical manifestations of asthma.
Methods: This study was a cross-sectional observational study. We collected blood samples from asthmatic patients (severe n=52, non-severe n=59) and healthy control subjects (HC, n=33). Concentrations of IL-36 cytokines in plasma were measured using the ELISA (R&D Systems).
Results: Concentrations of IL-36? were significantly elevated in the severe asthma patients, compared with the non-severe asthma (p=0.0002) and the HC (p=0.001). IL-38 concentrations were significantly decreased in the non-severe asthma patients, compared with HC (p=0.01). IL-38 and IL-36 receptor ? concentrations were correlated with FEV₁(r=0.25, p=0.002; r=0.22, p=0.009, respectively) and FVC (r=0.25 p=0.006; r=0.22, p=0.008, respectively).
Conclusions: General changes of the IL-36 subfamily are implied on the severity of asthma.