Interleukin 2 Activates Brain Microvascular Endothelial Cells Resulting in Destabilization of Adherens Junctions.

Abstract

The pleiotropic cytokine interleukin 2 (IL2) disrupts the blood-brain barrier and alters brain microcirculation, underlying vascular leak syndrome that complicates cancer immunotherapy with IL2. The microvascular effects of IL2 also play a role in the development of multiple sclerosis and other chronic neurological disorders. The mechanism of IL2-induced disruption of brain microcirculation has not been determined previously. We found that both human and murine brain microvascular endothelial cells express constituents of the IL2 receptor complex. Then we established that signaling through this receptor complex leads to activation of the transcription factor, nuclear factor κB, resulting in expression of proinflammatory interleukin 6 and monocyte chemoattractant protein 1. We also discovered that IL2 induces disruption of adherens junctions, concomitant with cytoskeletal reorganization, ultimately leading to increased endothelial cell permeability. IL2-induced phosphorylation of vascular endothelial cadherin (VE-cadherin), a constituent of adherens junctions, leads to dissociation of its stabilizing adaptor partners, p120-catenin and β-catenin. Increased phosphorylation of VE-cadherin was also accompanied by a reduction of Src homology 2 domain-containing protein-tyrosine phosphatase 2, known to maintain vascular barrier function. These results unravel the mechanism of deleterious effects induced by IL2 on brain microvascular endothelial cells and may inform the development of new measures to improve IL2 cancer immunotherapy, as well as treatments for autoimmune diseases affecting the central nervous system.

• Authors: Lukasz S Wylezinski, Jacek Hawiger
• Journal: The Journal of biological chemistry (J Biol Chem) Vol. 291 Issue 44 Pg. 22913-22923 (10 28 2016) ISSN: 1083-351X [Electronic] United States
• PMID: 27601468 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural)
• Copyright: © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Chemical References

• Chemokine CCL2
• Interleukin-2
• NF-kappa B
• beta Catenin

Topics

• Adherens Junctions (metabolism)
• Animals
• Blood-Brain Barrier (metabolism)
• Brain (blood supply, metabolism)
• Capillary Permeability
• Cells, Cultured
• Chemokine CCL2 (genetics, metabolism)
• Endothelial Cells (metabolism)
• Humans
• Interleukin-2 (adverse effects, genetics, metabolism)
• Mice
• Microvessels (metabolism)
• NF-kappa B (genetics, metabolism)
• Signal Transduction
• beta Catenin (genetics, metabolism)