Fig 2: Expression of inflammatory cytokines and chemokines in the originally established porcine bronchial epithelial (PBE) cell line in response to the activation of the Toll-like receptor 3 (TLR3) signaling pathway. PBE cells were seeded at an initial concentration of 1.0 x 104 cells/cm2. At day 6, PBE cells were stimulated with the TLR3 synthetic agonist poly(I:C) (100 ng/ml) and the expressions of the inflammatory factors TNF-a, IL-6, IL-8, and MCP-1 were evaluated by qPCR at the indicated time points. Results represent data from three independent experiments. Asterisks indicate significant differences between the control and the poly(I:C)-treated PBE cells. * (P < 0.05), ** (P < 0.01).

Fig 3: Expression of interferons (IFNs) and antiviral factors in the originally established porcine bronchial epithelial (PBE) cell line in response to the activation of the Toll-like receptor 3 (TLR3) signaling pathway. PBE cells were seeded at an initial concentration of 1.0 x 104 cells/cm2. At day 6, PBE cells were stimulated with the TLR3 synthetic agonist poly(I:C) (100 ng/ml) and the expressions of IFN-ß, IFN-?1 (IL-29), IFN-?3 (IL-28B) and the antiviral factors Mx1, OAS1, and PKR were evaluated by qPCR at the indicated time points. Results represent data from three independent experiments. Asterisks indicate significant differences between the control and the poly(I:C)-treated PBE cells. * (P < 0.05), ** (P < 0.01).

Fig 4: Expression of antiviral Pattern Recognition Receptors (PRRs) in the originally established porcine bronchial epithelial (PBE) cell line in response to the activation of the Toll-like receptor 3 (TLR3) signaling pathway. PBE cells were seeded at an initial concentration of 1.0 x 104 cells/cm2. At day 6, PBE cells were stimulated with the TLR3 synthetic agonist poly(I:C) (100 ng/ml) and the expressions of the PRRs RIG-1, and MDA5 were evaluated by qPCR at the indicated time points. Results represent data from three independent experiments. Asterisks indicate significant differences between the control and the poly(I:C)-treated PBE cells. * (P < 0.05), ** (P < 0.01).

Fig 5: Expression of negative regulators of the Toll-like receptor (TLR) signaling pathway in the originally established porcine bronchial epithelial (PBE) cell line in response to the activation of TLR3. PBE cells were seeded at an initial concentration of 1.0 x 104 cells/cm2. At day 6, PBE cells were stimulated with the TLR3 synthetic agonist poly(I:C) (100 ng/ml) and the expressions of the TLR negative regulators A20 and Bcl-3 were evaluated by qPCR at the indicated time points. Results represent data from three independent experiments. Asterisks indicate significant differences between the control and the poly(I:C)-treated PBE cells. * (P < 0.05), ** (P < 0.01).