Fig. 2

GC-derived exosomes promote M2-like polarization of intrahepatic macrophages. A. Representative fluorescence images of mouse liver, lung, brain, bone, and kidney tissues after injection of PKH26-labelled exosomes from MKN45 and MKN45-HL cells into the tail vein. B. Representative immunofluorescence showing colocalization between exosomes and macrophages (F4/80) in mouse liver after tail vein injection of PKH26-labeled exosomes. Scale bar = 50 μm. C, D. Representative immunofluorescence image showing internalization of PKH26-labeled MKN45/MKN45-HL-derived exosomes (red) by PMA-treated THP-1 cells. Scale bar = 20 μm. E, F. The expression of typical M2 markers (CD163, IL10, TGF-β, and VEGFA) and M1 markers (iNOS and TNFA) in PMA-treated THP-1 cells incubated with MKN45/MKN45-HL-derived exosomes or PBS (control) were examined by qRT-PCR. G. The effect of GC cell-derived exosomes on the expression of CD206 (M2 marker) was detected by flow cytometry. H. Immunostaining of CD206 (M2 marker) and F4/80 (macrophage marker) in livers of mice educated with PBS, MKN45 exosomes or MKN45-HL exosomes. Scale bar = 50 μm. Data are shown as mean ± standard deviation of 3 independent experiments, and statistical significance was determined using one-way ANOVA test (*P < 0.05, **P < 0.01, ***P < 0.001)