Potential role of MCP-1 in endothelial cell tight junction 'opening': signaling via Rho and Rho kinase

• Published in: Journal of cell science Vol. 116; no. Pt 22; pp. 4615 - 4628
• Main Authors: Stamatovic, Svetlana M, Keep, Richard F, Kunkel, Steven L, Andjelkovic, Anuska V
• Format: Journal Article
• Language: English
• Published: England 15.11.2003
• Subjects: Acute-Phase Proteins - metabolism; Animals; Brain - metabolism; Cells, Cultured; Chemokine CCL2 - metabolism; Claudin-5; Electric Impedance; Endothelial Cells - metabolism; Intracellular Signaling Peptides and Proteins; Inulin - metabolism; Membrane Proteins - metabolism; Mice; Mice, Knockout; Microscopy, Fluorescence; Mutation; Occludin; Octoxynol - metabolism; Oligonucleotide Array Sequence Analysis; Permeability - drug effects; Protein-Serine-Threonine Kinases - metabolism; Receptors, CCR2; Receptors, Chemokine - metabolism; rho-Associated Kinases; Stress Fibers - metabolism; Tight Junctions - metabolism; Zonula Occludens-2 Protein
• ISSN: 0021-9533; 1477-9137
• DOI: 10.1242/jcs.00755

The expression of the monocyte chemoattractant protein-1 (MCP-1) receptor CCR2 by brain endothelial cells suggests that MCP-1 may have other functions than purely driving leukocyte migration into brain parenchyma during inflammation. This study examines one of these potential novel roles of MCP-1 regulation of endothelial permeability using primary cultures of mouse brain endothelial cells. MCP-1 induces reorganization of actin cytoskeleton (stress fiber formation) and redistribution of tight junction proteins, ZO-1, ZO-2 occludin and claudin-5, from the Triton X-100-soluble to the Triton X-100-insoluble fractions. These morphological changes are associated with a decrease in transendothelial electrical membrane resistance and an increase in [14C]inulin permeability. MCP-1 did not induce these events in brain endothelial cells prepared from mice genotype CCR2-/-. The Rho kinase inhibitor Y27632 and inhibition of Rho (C3 exoenzyme, and dominant negative mutant of Rho, RhoT19N) prevented MCP-1-induced stress fiber assembly, reorganization of tight junction proteins and alterations in endothelial permeability. In all, this suggests that a small GTPase Rho and Rho kinase have a pivotal role in MCP-1-induced junction disarrangement. These data are the first to strongly suggest that MCP-1, via CCR2 present on brain endothelial cells, contributes to increased brain endothelial permeability.