Extracellular Vesicles in the Mesenchymal Stem Cell/Macrophage Axis: Potential Targets for Inflammatory Treatment.

Mesenchymal stem cells (MSCs) have been widely used for the treatment of autoimmune and inflammatory diseases due to their pluripotent differentiation potential and immunomodulatory function. Macrophage (Mφ) polarization also acts an essential and central role in regulating inflammation, basically the dynamic balance of pro-inflammatory M1-like (M1φ) and anti-inflammatory M2-like macrophages (M2φ), affecting the occurrence and progression of inflammatory diseases. Since a pivotal molecular crosstalk between MSCs and Mφ has been elucidated using in vitro and in vivo preclinical studies, we presume that the mesenchymal stem cell/macrophages axis (MSC/Mφ axis) acts an important role in pathophysiological mechanisms of inflammatory diseases and should be the potential therapeutic target. However, the crucial effects of EVs as intercellular communicators and therapeutic agents in the MSC/Mφ axis remains explorable. Therefore, this review elaborated on the mechanisms of EVs mediating the MSC/Mφ axis regulating inflammation in-depth, hoping to provide more references for related research in the future.