M2 Macrophages Promote PDGFRβ+ Pericytes Migration After Spinal Cord Injury in Mice via PDGFB/PDGFRβ Pathway

Spinal cord injury (SCI) can lead to severe sensory and motor dysfunction, and current clinical treatments are not very effective. After SCI, a fibrotic scar forms, which prevents the regeneration of nerve fibers. This study investigates how macrophages, a type of immune cell, and pericytes, cells that contribute to the fibrotic scar, interact after SCI. The study found that M2 macrophages, a specific type of macrophage, promote the migration of PDGFRβ+ pericytes to the injury site. This migration is facilitated by the PDGFB/PDGFRβ pathway, a signaling pathway involving growth factors and their receptors. Blocking this pathway with a specific inhibitor (SU16f) can reduce pericyte migration. These findings suggest that the PDGFB/PDGFRβ pathway could be a potential therapeutic target for treating SCI by reducing fibrotic scar formation and promoting nerve regeneration. The researchers found that M2 macrophages also promote the secretion of extracellular matrix.

• 1
  Macrophages and PDGFRβ+ pericytes exhibit a closely related spatiotemporal distribution in the injury core after SCI.
• 2
  M2 macrophages promote the migration of PDGFRβ+ pericytes in vitro, potentially due to the secretion of certain cytokines.
• 3
  M2 macrophages secrete PDGFB acting on PDGFRβ to promote PDGFRβ+ pericytes migration in vitro, and this effect can be blocked by SU16f.