Fig. 2

Specific ligands for TLR3 and RIG-I-like receptors trigger production of IL-33 in BSMCs. BSMCs from healthy subjects were stimulated with different concentrations of dsRNA and dsRNA/LyoVec (dsRNA/LV). IL-33 mRNA expression (a, b) was analysed after 3 and 24 h by RT-qPCR and IL-33 protein was determined by western blot after 24 h (d). Cells were also pretreated with 10 μg/ml of the TLR3 inhibitor chloroquine (Cq) (a, b and d). The effect of 1 μg/ml dexamethasone (Dex) on 10 μg/ml dsRNA-induced IL-33 expression was evaluated in healthy (c, d) and asthmatic BSMCs (c) after 24 h stimulation. Data are presented as mean with SEM and n = 6 independent experiments from three BSMC donors. *p ≤ 0.05, **p ≤ 0.01 and ***p ≤ 0.001 compared to control if not otherwise indicated and ^### p compared to 10 μg/ml dsRNA. A representative western blot image of IL-33 protein is shown