Induction of Macrophage M2bc Polarization by Adipose Tissue-Derived Mesenchymal Stem Cells

Abstract EN

Background.

Adipose-derived mesenchymal stem cells (ADMSCs) can promote healing and inhibit inflammation/immune response in local tissues, while the detailed mechanism remains unknown.

Results.

ADMSCs and peritoneal macrophages were collected from C57BL/6 mice.

The culture medium (CM) from ADMSCs (24 hours cultured) was collected.

The CM was added to the Mφ culture system with lipopolysaccharide (LPS) or IL-4/IL-13 or blank.

And those Mφ cultures without adding CM were used as controls.

A series of classification markers and signaling pathways for Mφ polarization were detected by using flow cytometry, RT-PCR, and western blotting.

Furthermore, the cell viability of all the groups was detected by CCK8 assay.

After CM induction in different groups, M1-Mφ markers and M2a-Mφ were decreased; however, M2b/c-Mφ markers increased.

STAT3/SOCS3 and STAT6/IRF4 were suppressed in all 3 CM-treated groups.

Moreover, the cell viability of all 3 groups which were induced by CM significantly increased as compared to that of the control groups without adding CM.

Conclusion.

ADMSCs can induce nonactivated macrophage and M1-Mφ into M2b/c-Mφ.

Downregulation of the STAT3 and STAT6 pathway may involve in this process.

This data shows that the anti-inflammatory role of ADMSC in local tissues may be partly due to their effect on Mφ to M2b/c-Mφ.