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Figure 1 | BMC Immunology

Figure 1

From: Streptococcus pneumoniae synergizes with nontypeable Haemophilus influenzae to induce inflammation via upregulating TLR2

Figure 1

S. pneumoniae induces TLR2 up-regulation via pneumolysin in the epithelium of lung and middle ear. (A) Time dependence of TLR2 up-regulation in response to S. pneumoniae (S.p.). HeLa cells were treated with S.p. for 1, 3, 5 and 7 hours, and relative quantity of TLR2 mRNA expression was measured by Q-PCR analysis. (B)S.p.-induced TLR2 mRNA expression in lung epithelial cell A549. Cells were treated with S.p., and relative quantity of TLR2 mRNA expression was measured by Q-PCR analysis 5 hours after treatment. (C) S.p.-induced TLR2 promoter activity. HeLa cells were transiently transfected with TLR2 luciferase reporter gene, treated with S.p., and relative luciferase activity was measured 5 hours after treatment. (D) The effects of S.p. WT strain D39 and PLY-deficient strain PLN on S.p.-induced TLR2 expression. Cells were treated either with S.p. D39 or PLN, and mRNA expression of TLR2 was measured by Q-PCR analysis 3 hours after treatment. (E) S.p.- and PLY-induced TLR2 mRNA expression in middle ear cell HMEEC-1. Cells were treated with S.p. or PLY, and TLR2 mRNA expression was measured 5 hours after treatment by Q-PCR analysis. (F & G) S.p.- and PLY-induced TLR2 expressions in the lung and middle ear of the mice. Wild-type mice were intratracheally inoculated with S.p. or PLY for S.p.-induced pneumonia (F) and inoculated into the middle ear through tympanic membrane for S.p.-induced otitis media model (G). Relative quantity of TLR2 mRNA was measured from the lungs of inoculated mice 3 hours after inoculation and from the middle ears of inoculated mice 9 hours after inoculation. (H) The effect of PLY on S.p.-induced TLR2 expression was measured using S.p. WT strain D39 and PLY-deficient strain PLN in mice in vivo. WT mice were intratracheally inoculated with S.p. D39 or PLN, or purified PLY, and TLR2 mRNA expression was measured from the lungs of inoculated mice 9 hours after inoculation by Q-PCR analysis. (I) Protein expression of TLR2 is up-regulated following S.p. infection. TLR2 protein expression was measured from the lungs WT mice inoculated with S.p. by western blotting analysis 6 hours after inoculation (left panel), and band data was analyzed using Kodak Image analysis system and data was presented as Fold induction (right panel). Data are means ± S.D. (n = 3). *, p < 0.05 compared with CON, **, p < 0.01 compared with CON, ***, p < 0.05 compared with S.p. D39, CON, control.

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