Effect of lipopolysaccharide on TLR4 expression in NPDFs.

<p>NPDFs were stimulated with LPS (10 µg/mL) in the presence or absence of each MAPK inhibitor, including U0126 (10 µM), SB203580 (10 µM), and SP600125 (10 µM). mRNA expression level of <i>TLR4</i> was determined using real-time PCR (A). TLR4 protein expression level was examined using immunocytochemical staining (B), western blotting (C) and density analysis (D). Phosphorylation of MAPK pathways involving pERK, pJNK, and p-p38 was measured using western blotting (E) and density analysis (F). Expression of GAPDH was determined as an internal control. Values are the mean ± SEM of independent samples. *Significant difference from control (* P<0.05). †Significant difference from LPS († P<0.05). Images were acquired and visualized using confocal laser scanning microscopy. Scale bar  = 20 µm.</p

Inhibitory effect of TLR4 antagonist on pro-inflammatory cytokines and MMP-1 production in NPDFs.

<p>NPDFs were stimulated with LPS in the presence or absence of LPS-RS, a TLR4 antagonist. mRNA expression levels of <i>TLR4</i>, <i>IL-6</i>, <i>IL-8</i>, and <i>MMP-1</i> were determined using real-time PCR (A, E, and G). Protein expression levels of TLR4 and MMP-1 were examined using western blotting (B and H), density analysis (C and I) and immunocytochemical staining (D). (F) Production of IL-6 and IL-8 was measured using ELISA. (J) MMP-1 secretion was measured using collagen zymography. Values are mean ± SEM of independent samples. *Significant difference from control (* P<0.05 and ** P<0.01). †Significant difference from LPS († P<0.05 and †† P<0.01). Images were acquired and visualized using confocal laser scanning microscopy. Scale bar  = 20 µm.</p

Expression of MMP-1 in inferior turbinate and nasal polyps.

<p>Protein expression level of MMP-1 based on western blot analysis (A) and density analysis (B). (C) The expression pattern and localization of MMP-1 based on immunofluorescence staining. Images were acquired and visualized using confocal z-stack laser scanning microscopy. Values are the mean ± SEM of independent samples. Asterisks (*) indicate statistically significant differences (P<0.05). Scale bar  = 50 µm.</p

Inhibitory effect of TLR4 antagonist on pro-inflammatory cytokines and MMP-1 production in nasal polyp organ cultures.

<p>Nasal polyp tissues were cultured and stimulated with LPS with or without LPS-RS. (A) Production of IL-6 and IL-8 was measured using ELISA. Protein expression level of MMP-1 was examined using western blotting (B) and density analysis (C). (D) MMP-1 secretion was measured using collagen zymography. Secretion of MMP-2 and MMP-9 was measured using gelatin zymography. (E) The expression pattern and localization of MMP-1 by immunohistochemical staining. Values are mean ± SEM of three independent samples. Significant difference from control (* P<0.05 and ** P<0.01; † P<0.05 compared with LPS). Images were acquired and visualized using confocal z-stack laser scanning microscopy. Scale bar  = 20 µm.</p

Schematic diagram for effect of lipopolysaccharide in nasal polyp-derived fibroblast and organ culture.

<p>Schematic diagram for effect of lipopolysaccharide in nasal polyp-derived fibroblast and organ culture.</p

Effect of lipopolysaccharide on MMP expression in NPDFs.

<p>NPDFs were stimulated with LPS in the presence or absence of each MAPK inhibitor. Expression levels of <i>MMP-1</i>, <i>MMP-2</i>, and <i>MMP-9</i> were determined using real-time PCR (A), western blotting (B) and density analysis (C). (D) MMP-1 secretion was measured using collagen zymography. MMP-2 and MMP-9 secretion levels were measured using gelatin zymography. (E) The effect of inhibiting the MAPK pathway on <i>MMP-1</i> mRNA expression was examined using real-time PCR. Values are mean ± SEM of independent samples. * P<0.05 and ** P<0.01 compared with control; † P<0.05 compared with LPS.</p

Genes significantly upregulated in LPS-induced NPDFs.

<p>Genes significantly upregulated in LPS-induced NPDFs.</p

Sequences of RT-PCR oligonucleotide primers.

<p>Sequences of RT-PCR oligonucleotide primers.</p