siRNA-mediated silencing of Dectin-1 in human epithelial cells. (A) Dectin-1 mRNA expression in BEAS-2B cells left untreated or stimulated with β-glucan (β-glu) or heat-inactivated A conidia (Asp) after 48 hours of transfection with a Dectin-1-specific siRNA (siDectin-1) or a nonspecific control siRNA (siNS). Transfection efficiencies were determined with a positive fluorescent-labeled transfection control siRNA, and the silencing effects of siRNAs were confirmed by RT-PCR. Results shown were assessed in triplicate. (B) Cytokine production (picograms per milliliter) on culture supernatants of transfected BEAS-2B cells stimulated overnight with either β-glucan or heat-inactivated A conidia. Cytokines were quantified by ELISA, and the results shown were assessed in triplicate. The detection limit of the assays was less than 0.5 pg/mL for each cytokine.