Background Microglia are the primary immunocompetent cells in brain tissue,and microglia-mediated inflammation is associated with the pathogenesis of various neuronal disorders.Recently,many studies have shown that the BMSCs displayed a remarkable ability to modulate inflammatory and immune responses through the release of a variety of bioactive molecules,protecting the CNS.Previously,we reported that BMSCs have the ability to modulate inflammatory responses in a Traumatic brain injury (TBI) model and that the potential mechanisms may be partially attributed to upregulated TSG-6 expression.However,whether TSG-6 exerts an anti-inflammatory effect by affecting microglia is not fully understood.In this study,we investigated the anti-inflammatory effects of BMSCs and TSG-6 in an in vitro LPS-induced BV2 microglial activation model.