Figure 1.

The central role of Mesenchymal Stem Cells (MSC) in immune responses. The above figure distinguishes the response and interaction of MSCs in pro-inflammatory and anti-inflammatory conditions on immune cells. These effects demonstrate cell-to-cell contact-mediated immunosuppression of B and T cell proliferation, induction and transforming growth factor-β (TGF-β)/hepatocyte growth factor (HGF) mediated regulation of regulatory T cells. Also, it shows the capacity of immunomodulation of MSCs by inhibiting the natural killer (NK) cells, dendritic cells (DCs) at various maturation stages as well as macrophage polarization dependency on the microenvironment.