Fig. 6

Downregulation of MRF in MSCs inhibits the recruitment of human monocytes and enhances MSC immunosuppressive function on macrophage polarization in vivo. A Schematic diagram of human monocyte recruitment in vivo. A human monocyte-transferred mouse model was constructed by injection of CFSE-labeled human CD14+ monocytes via the tail vein. After the injection of MSCs or si-MRF MSCs, the mice were sacrificed to collect peritoneal lavage fluid and spleen cells for flow cytometric analysis. B MRF-knockdown MSCs disrupted the recruitment of human monocytes into the peritoneal cavity (n = 9). C CFSE-labeled monocytes in the spleen cell population did not differ obviously among the groups (n = 9). D The proportion of CFSE-labeled monocytes in the peritoneal lavage fluid is shown as a histogram. E The proportion of CFSE-labeled monocytes in the spleen cell population is shown as a histogram. F The proportion of CFSE-labeled cells in peritoneal lavage fluid was calibrated to the percentage of CFSE-labeled monocytes in the spleen. G Schematic diagram of human macrophage polarization in vivo. Human MSCs/si-MRF MSCs and human macrophages labeled with CFSE were simultaneously injected intraperitoneally, and 2 days later, the mice were sacrificed to collect peritoneal lavage fluid for flow cytometric analysis. H The MFI of human HLA-DR (left panel) and CD206 (right panel) was detected in CFSE-labeled cells via flow cytometric analysis (n = 6). I Histogram showing the MFI of HLA-DR among the groups co-injected without MSCs, with MSCs and with MRF-knockdown MSCs. J Histogram showing the MFI of CD206 among the groups co-injected without MSCs, with MSCs and with MRF-knockdown MSCs. The data are presented as the means ± SDs; *P < 0.05, **P < 0.01, ***P < 0.001, ns not significant