Shuvaev, Vladimir V.Han, JingyanTliba, SamiraArguiri, EvgueniaChristofidou-Solomidou, MelpoRamirez, Servio H.Dykstra, HollyPersidsky, YuriAtochin, DmitriyHuang, PaulMuzykantov, Vladimir R.2014-03-102013Shuvaev, V. V., J. Han, S. Tliba, E. Arguiri, M. Christofidou-Solomidou, S. H. Ramirez, H. Dykstra, et al. 2013. “Anti-Inflammatory Effect of Targeted Delivery of SOD to Endothelium: Mechanism, Synergism with NO Donors and Protective Effects In Vitro and In Vivo.” PLoS ONE 8 (10): e77002. doi:10.1371/journal.pone.0077002. http://dx.doi.org/10.1371/journal.pone.0077002.1932-6203http://nrs.harvard.edu/urn-3:HUL.InstRepos:11878887Pro-inflammatory activation of vascular endothelium is implicated in pathogenesis of severe conditions including stroke, infarction and sepsis. We have recently reported that superoxide dismutase (SOD) conjugated with antibodies (Ab/SOD) that provide targeted delivery into endothelial endosomes mitigates inflammatory endothelial activation by cytokines and agonists of Toll-like receptors (TLR). The goal of this study was to appraise potential utility and define the mechanism of this effect. Ab/SOD, but not non-targeted SOD injected in mice alleviated endotoxin-induced leukocyte adhesion in the cerebral vasculature and protected brain from ischemia-reperfusion injury. Transfection of endothelial cells with SOD, but not catalase inhibited NFκB signaling and expression of Vascular Cell Adhesion Molecule-1 induced by both cytokines and TLR agonists. These results affirmed that Ab/SOD-quenched superoxide anion produced by endothelial cells in response to proinflammatory agents mediates NFκB activation. Furthermore, Ab/SOD potentiates anti-inflammatory effect of NO donors in endothelial cells in vitro, as well as in the endotoxin-challenged mice. These results demonstrate the central role of intracellular superoxide as a mediator of pro-inflammatory activation of endothelium and support the notion of utility of targeted interception of this signaling pathway for management of acute vascular inflammation.en-USJournal Article2014-03-1010.1371/journal.pone.0077002