Objective   To investigate the effects of JAK2-STAT3 signaling pathway on lipopolysaccharide(LPS)-induced activation of microglia and the possible mechanisms.    Methods   Immunohistochemistry and flow cytometry were applied to observe the changes in OX-42. Changes in TNF-α expression after stimulation with LPS were detected by ELISA. The phosphorylation levels of JAK2 and STAT3 were detected by Western-blot.     Results   LPS stimulation significantly increased the number of the positive cells of OX-42

enhanced TNF-α expression

and up-regulated the phosphorylation level of JAK2 and STAT3.     Conclusion   LPS may induce the microglia activation through the activation of the JAK2-STAT3 signaling pathway and promote the secretion of TNF-α

suggesting that activation of the JAK2-STAT3 signaling pathway may be associated with the secretion of the inflammatory factors.