Bone Marrow Mesenchymal Stem Cell-Derived Exosomes Accelerate Functional Recovery After Spinal Cord Injury by Promoting the Phagocytosis of Macrophages to Clean Myelin Debris

• DOI: 10.3389/fcell.2021.772205
• Publication Date: 2021-11-08T05:33:06Z
• Authors: Xiaolong Sheng; Jinyun Zhao; Miao Li; Yan Xu; Yi Zhou; Jiaqi Xu; Rundong He; Hongbin Lu; Tianding Wu; Chunyue Duan; Yong Cao; Jianzhong Hu
• Keywords: 0301 basic medicine; Cell and Developmental Biology; 03 medical and health sciences; QH301-705.5; BMSC derived exosomes; phagocytosis; myelin debris; macrophage; Biology (General); spinal cord injury; 3. Good health

Macrophage phagocytosis contributes predominantly to processing central nervous system (CNS) debris and further facilitates neurological function restoration after CNS injury. The aims of this study were evaluate the effect bone marrow mesenchymal stem cells (BMSC)-derived exosomes (BMSC-Exos) on phagocytic capability macrophages clear myelin investigate underlying molecular mechanism during spinal cord injury (SCI) process. This work reveals that monocyte-derived (MDMs) infiltrating into SCI site could efficiently engulf process material. However, ability tissue is compromised SCI. administration BMSC-Exos as an approach for treatment rescue macrophage normal by improving internalization, which beneficial repair, evidenced better axon regrowth increased hindlimb locomotor functional recovery in a rodent model. Examination with revealed promote capacity phagocytose vitro create regenerative microenvironment regrowth. In addition, we confirmed BMSC-Exo resulted improved engulfed promoting expression receptor collagenous structure (MARCO) macrophages. inhibition MARCO PolyG (a antagonist) impaired clearance at lesion site, leading damage healing conclusion, these data indicated targeting may have therapeutic potential improvement cell-free immune therapy strategy has wide application prospects treatment.