Conclusion
hUCMSCs significantly polarize the lipopolysaccharide-stimulated RAW264.7 macrophages from a pro-inflammatory M1 subpopulation to an intermediate subpopulation of anti-inflammatory M2 macrophages, which are associated with a gradual decrease of iNOS and PGE2 levels.
Methods
Lipopolysaccharide-stimulated RAW264.7 macrophages were co-cultured with hUCMSCs in a Transwell system for 4 d, and then labelled with anti-F4/80, anti-CD86, and anti-CD206 antibodies for flow cytometry. The co-cultured supernatants were detected by enzyme-linked immunosorbent assay for prostaglandin E2. The co-cultured RAW264.7 macrophages were also lysed to measure the intracellular level of inducible nitric oxide synthase.
Objective
To investigate the effects of human umbilical cord mesenchymal stem cells (hUCMSCs) on the polarization of lipopolysaccharide-stimulated RAW264.7 macrophages.
Results
There were significantly more F4/80+CD86+CD206+ RAW264.7 macrophages in the hUCMSCs-treated groups than the control group (P<0.001). The secretion of prostaglandin E2 by lipopolysaccharide-stimulated RAW264.7 macrophages was significantly inhibited in a dose-dependent manner with the addition of hUCMSCs (P<0.001). The expression of iNOS, the intracellular marker of M1 cells, was also significantly inhibited by hUCMSCs (P<0.05).