Fig. 2.

The mRNA and surface expression levels of C3aR are down-regulated in the presence of the H4R agonist ST-1006 during the differentiation process of M2 macrophages. a Primary human monocytes were differentiated into M2 macrophages (M-CSF, 10 ng/mL) for 10 days in the presence of histamine (10 µM) or ST-1006 (10 µM) or left non-stimulated. b C3aR mRNA expression was analysed by quantitative PCR and calculated by the [delta] [delta] Ct method normalized to the non-stimulated samples. c C3aR surface expression was detected by flow cytometry. d Overlay of the histograms of one representative experiment out of the 7 is shown. Significant differences, as determined by the Wilcoxon signed rank test, are indicated as follows: * p < 0.05; medians are shown in the graphs. ns, non-stimulated; Hist, histamine; MFI, mean fluorescence intensity.