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.