N2-Polarized Neutrophils Guide Bone Mesenchymal Stem Cell Recruitment and Initiate Bone Regeneration: A Missing Piece of the Bone Regeneration Puzzle.

ABSTRACT: The role of neutrophils in bone regeneration remains elusive. In this study, it is shown that intramuscular implantation of interleukin-8 (IL-8) (commonly recognized as a chemotactic cytokine for neutrophils) at different levels lead to outcomes resembling those of fracture hematoma at various stages. Ectopic endochondral ossification is induced by certain levels of IL-8, during which neutrophils are recruited to the implanted site and are N2-polarized, which then secrete stromal cell-derived factor-1α (SDF-1α) for bone mesenchymal stem cell (BMSC) chemotaxis via the SDF-1/CXCR4 (C-X-C motif chemokine receptor 4) axis and its downstream phosphatidylinositol 3'-kinase (PI3K)/Akt pathway and β-catenin-mediated migration. Neutrophils are pivotal for recruiting and orchestrating innate and ada

SUBMITTER: Cai B 

PROVIDER: S-EPMC8498914 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature