IRF-5 accelerates leukocyte adhesion to endothelial cells in ischemia-reperfusion injury through regulating the transcription of VCAM-1.

Ischemia-reperfusion injury (IRI) has been implicated in many pathological conditions, including cardiovascular diseases. Adhesion of leukocytes to the surface of endothelial cells has been considered as one of the principle steps in the pathological cascade of inflammatory tissue damage during IRI. The role of the transcriptional factor interferon regulatory factor-5 (IRF-5) in endothelial physiology remains unknown. Here, we report that IRF-5 is expressed in human umbilical vein endothelial cells (HUVECs) and is rapidly upregulated in response to IRI, mediated by the JAK2/STAT3 pathway. Importantly, IRF-5 is involved in IRI-induced attachment of THP-1 leukocytes to HUVECs. Mechanistically, it was found that IRF-5 targeted the expression of vascular cell adhesion molecule 1 (VCAM-1) at the transcriptional level by binding to its promoter. In conclusion, we identify IRF-5 as a new regulator and thus a therapeutic target in IRI-driven cardiovascular pathologies.