MECs alter their cytokine and chemokine secretion profile upon uptake of apoptotic bodies. (A) Ben-Men-I cells were treated with PMA, LPS, and left untreated or were incubated with unlabeled apoptotic U-937 cells at a ratio of 1:5 for 24 h. Cell culture supernatants were analyzed for 36 different cytokines and chemokines using an antibody array. The array is organized in five rows (A-E) and 10 columns (1-10) with two spots for each analyte (R = positive control, N = negative control). Please note that spots corresponding to IL-1 receptor antagonist (marked with %) were weak but distinguishable to the eye. Differences in cytokine secretion between control and treatment groups are depicted in qualitative heat maps. (B) Ben-Men-I cells were incubated with unlabeled apoptotic U-937 cells at a ratio of 1:1 or 1:5 for 24 h and the concentration of IL-6 in culture supernatant was measured by ELISA. IL-6 was measured in supernatant of apoptotic cells and subtracted as background from MECs treated with apoptotic cells. Shown is the average of three independent experiments with the error bars representing SD. Statistical significance was assessed using Student’s t-test (*P <0.05). Ben-Men-I cells were treated as in (B) and with concentrations of (C) IL-8, (D) Il-16, (E) CXCL1, (F) MIF (# represents P = 0.067), and (G) IL-1 receptor antagonist were measured by ELISA. Shown is the average of three independent experiments with the error bars representing SD. Statistical significance was analyzed by one-way ANOVA. P values were determined using pair-wise Student’s t-test adjusted according to Holm (# P <0.1; * P <0.05; ** P <0.01; *** P <0.001). Marked are the comparisons between the control (1:0) and treatment groups.