Mesenchymal stem cells regulating macrophage polarization

Mesenchymal stem cells possess not only multilineage differentiation and self-renewal capabilities but also immunomodulatory functions. Macrophages are a critical component of innate immunity and can undergo polarization upon stimulation, with M1 and M2 macrophages exhibiting distinct surface markers, cytokine secretion profiles, and functional properties. Mesenchymal stem cells regulate macrophage polarization through multiple mechanisms, among which paracrine effects play a predominant role. In this review, we discuss the mechanisms underlying mesenchymal stem cells-mediated regulation of macrophage polarization, with a particular focus on paracrine signaling, as well as preconditioning strategies-Especially proinflammatory cytokine pretreatment-That influence the ability of mesenchymal stem cells to modulate macrophage polarization.