Fig. 3

IHvKp-exo induces lung injury by affecting macrophage inflammation and polarization. A Lung tissue identification. The inflammatory response in lung tissues of mice injected with iHvKp-exo or control exosomes or PBS for 24 h was determined by HE staining. B Recruitment of inflammatory cells assessed by MPO activity. C Lung permeability was assessed by measuring BALF total protein concentration using a BCA assay. D Levels of pro-inflammatory cytokines measured by RT-PCR. E Immunofluorescence intensity of macrophage polarization markers in lung tissues, iNOS (green, M1) and Arg1 (red, M2). F MiR-155-5p expression in lung tissues measured by RT-PCR. G Uptake of exosomes in lung tissues. Exosomes labeled with PKH67 (green, green arrow) and macrophages labeled with CD68 (red, red arrow). Data are represented as mean ± SEM, *p < 0.05, **p < 0.01, ***p < 0.001, n = 3