Human bone marrow mesenchymal stem cells-derived exosomes protect against nerve injury via regulating immune microenvironment in neonatal hypoxic-ischemic brain damage model.

Neonatal hypoxic-ischemic (HI) brain injury is a serious injury caused by various perinatal factors, which has become a heavy mental burden to the family. The molecular mechanism underlying neonatal hypoxic-ischemic brain injury remains largely unknown. Human bone marrow mesenchymal stem cells (hBMSCs) have caused wide public concern due to the immunomodulatory properties. Exosomes can polarize human microglia and thus changed it into an anti-inflammatory phenotype to reduce the release of pro-inflammatory factors. However, it is unclear whether hBMSCs-exosomes have effect on neonatal hypoxic-ischemic brain injury. In this study, we aimed at investigating the role of hBMSCs-exosomes in regulating immune response and nerve injury in neonatal hypoxic-ischemic brain damage model. In the research, we identified the exosome secretion of hBMSCs could transferred into human microglia (HMC). Moreover, we determined the importance of hBMSCs-exosomes in regulating HMC polarization and inflammatory response. Our research findings might provide a new insight into slowing the disease progression of neonatal hypoxic-ischemic brain injury.