Figure 2.

Effect of TLR2 silencing on IL-8 secretion by A549 cells incubated with P. brasiliensis yeasts or PAM₃CSK₄. A549 cells were transfected with siRNA directed to TLR2 (siRNA TLR2) or negative control siRNA (NC), and then incubated with P. brasiliensis yeasts (MOI = 2.5) (Pb 24 h +) or with 5 μg/mL of the TLR2-specific ligand PAM₃CSK₄. After 24 h, epithelial cells were lysed and aliquots were submitted to SDS–PAGE and Western blot, using anti-TLR2 antibodies (a,c). β-actin was used as loading protein control. Relative TLR2 levels were determined by densitometric analysis of the bands (a,c). (b,d) Cell supernatants were collected, and IL-8 levels of siRNA-transfected A549 cells, during incubation with P. brasiliensis yeasts or with PAM₃CSK₄, were analysed by ELISA. Values represent the mean of triplicate experiments ± standard deviation. *, p < 0.01 when compared to A549 cells transfected with NC in the absence of P. brasiliensis or PAM₃CSK₄. **, p < 0.01 when compared to A549 cells transfected with NC and incubated with P. brasiliensis yeasts or PAM₃CSK₄. Uncropped images are presented in Supplementary Fig. S2.