Role of Lipocalin-2 in N1/N2 Neutrophil Polarization After Stroke

Background: Neutrophils and Lipocalin-2 (LCN2) play pivotal roles in cerebral ischemiareperfusion (I/R) injury. However, their contribution is not fully clarified. Objective: This study aimed to explore the role of LCN2 and its association with neutrophil polarization in I/R injury. Methods: A mouse model of middle cerebral artery occlusion (MCAO) was used to induce cerebral ischemia. LCN2mAb was administered 1 h and Anti-Ly6G was administered for 3d before MCAO. The role of LCN2 in the polarity transition of neutrophils was explored using an in vitro HL-60 cell model. Results: LCN2mAb pretreatment had neuroprotective effects in mice. The expression of Ly6G was not significantly different, but the expression of N2 neutrophils was increased. In the in vitro study, LCN2mAb-treated N1-HL-60 cells induced N2-HL-60 polarization. Conclusion: LCN2 may affect the prognosis of ischemic stroke by mediating neutrophil polarization.