CCR2 Positive Exosome Released by Mesenchymal Stem Cells Suppresses Macrophage Functions and Alleviates Ischemia/Reperfusion-Induced Renal Injury

Figure 1

Identification of CCR2 as a key component highly expressed on MSC-derived exosomes (MSC-exo). (a) Screening of specific expressed proteins in bone marrow MSC-derived exosomes (MSC-exo) and NIH3T3 cells-derived exosomes (NIH3T3-exo) by ELISA with three repeat samples in each group. (b) WB analysis of protein expression levels for exosomes and cells. CD63 or GAPDH was used as an internal reference protein for exosomes and cells, respectively. The gray levels of blots were analyzed and the ratios of interesting gene/reference gene were shown. (c)-(d) Competitive analysis for the binding ability of CCR2 positive exosomes. Recombinant mouse CCL2 protein (100 ng per well) was incubated with exosomes in different concentrations for 1 hour. Then these exosomes were removed by ultracentrifugation. The free CCL2 protein levels in the medium were then determined by ELISA analysis and the ratios of free CCL2/total CCL2 were shown (d). Bars represent standard error of the mean ± S.D from three repeats. All the significance was determined by ANOVA and Student’s -test. .

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