Figure 4.

EP suppresses CpG B- and R848-induced DC activation by decreasing cytokine production and surface costimulatory molecules. DCs were pre-treated with 10mM EP for 1 h before stimulation with CpG B 10 μg/ml or R848 1 μg/ml. Cells and supernatants were harvested 24 h and 6 or 24 h post-stimulation, respectively, and analyzed by ELISA for cytokine levels and by flow cytometry for surface costimulatory molecule expression. EP decreases CD40 expression (A) and production of TNF-a (B,F), IL-6 (C,G), IL-10 (E), and IL-12p70 (D,H) upon CpG B (A–D) and R848 (A,E–H) stimulation. Results are the average of biological replicates from 2 to 3 independent experiments (n = 2–3) and are expressed as mean ± SEM. Data was analyzed using the two-tailed unpaired Student's t-test. *P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.0001.