IFN-α production induced by live RSV in pDC depends on CD14.

<p>The role of the TLR4/CD14/MD2 complex in the IFN-α and IL-6 response by PBMC after RSV infection (strain A2, MOI 5) was investigated (<b>A</b>) with a blocking monoclonal antibody specific for human TLR4 (20µg/ml), (<b>B</b>) the MD2 antagonist lipopolysaccharide from the bacterium <i>Rhodobacter </i><i>sphaeroides</i> (1µg/ml) or (<b>C</b>) via neutralization of CD14 with monoclonal antibody MY4 (10µg/ml). (<b>A</b>-<b>C</b>) Cytokine responses were measured by ELISA. Control stimuli; LPS: 10ng/ml, ODN: 5µg/ml. (<b>D</b>) A549 epithelial cells were co-cultured with PBMC, CD14⁺ cell depleted PBMC, pDC depleted PBMC, or CD14⁺ and BDCA-4⁺ double depleted PBMC, in the presence of RSV at MOI 5, ODN 2216 or no stimulus, for a period of 20 hrs. IL-6 and IFN-α production were measured by ELISA. Experiments were performed in 3 different donors with similar results. Data represent the mean ± SEM of triplicate measurements within 1 donor and were analyzed using one way ANOVA followed by a Bonferroni post-test. ns not significant, *P<0.05, **P<0.01.