CD99 mediates neutrophil transmigration through the bEnd.3 monolayer via the induction of oxygen-glucose deprivation

Abstract Aim/background CD99 participate in neutrophil infiltration after inflammatory events; however, despite the important role of inflammation in ischemic stroke, the role of CD99 in ischemic stroke remains unclear. Method In the present study, we detected the protein expression of CD99, ICAM-1, and CD31 (PECAM-1) in oxygen-glucose deprivation (OGD)-induced bEnd.3 cells and neutrophils and explored the influence of HIF-1α and IL-1β on their expression. We also explored the role of CD99 in the OGD-induced transmigration of neutrophils. Results Our results showed that OGD induction upregulated CD99 in bEnd.3 cells and that this effect could be abolished by the preadministration of IL-1β and was not mediated by HIF-1α. However, the activation of ICAM-1 by OGD remained activated with IL-1β treatment. No significant influence of IL-1β on OGD-induced CD31. Finally, we found a significant increase in infiltrated neutrophils after OGD induction compared with the control and OGD + anti-CD99 groups. Conclusion Our results indicated that CD99 mediates neutrophil infiltration and transmigration via OGD induction and thus constitutes a potential therapeutic target for anti-inflammatory treatment after ischemic stroke.