Inflammatory chemokines produced in AAA tissues trigger the expression of chemokines by VSMC.

<p>The graphs represent the relative concentrations of IL-1β, IL-17A, IL-22, IL-31, IL-23, IFNγ, TNF-α and CD40L that were assessed by ELISA assays on conditioned medium prepared from the media (M) and adventitia (A) of AAAs (n = 15) and control aortas (n = 15; §, #, †, p<0.05 vs Control A, AAA M and AAA A, respectively). The tables represent the expression of CCL19, CCL20, CCL21, CXCL13, and CXCL16 chemokines by human VSMCs that were stimulated for 15 hours with rIL-1β (5 ng/mL), rIL-17A (50 ng/mL), rIL-22 (10 ng/mL), rIL-31 (50 ng/mL), rIL-23 (25 ng/mL), rIFNγ (10 ng/mL), rTNF-α (1 ng/mL), and rCD40L (100 ng/mL). These cytokine concentrations were 2 log higher than those detected in the conditioned medium, so as to compensate for the <i>in vivo</i> situation where cells are subjected to chronic, additive and combined stimulations. The relative expression was determined by RT-qPCR on extracted RNA, and data were analyzed using the 2^−ΔΔCt Pfaffl formula <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0116295#pone.0116295-Pfaffl1" target="_blank">[30]</a> in which Ct values from stimulated VSMCs were compared to unstimulated cells, and normalized to the Ct values of β-actin. Data are representative of 4 independent experiments.