First Author | Yao Y | Year | 2011 |
Journal | J Cell Sci | Volume | 124 |
Issue | Pt 9 | Pages | 1486-95 |
PubMed ID | 21486949 | Mgi Jnum | J:182952 |
Mgi Id | MGI:5317232 | Doi | 10.1242/jcs.082834 |
Citation | Yao Y, et al. (2011) Truncation of monocyte chemoattractant protein 1 by plasmin promotes blood-brain barrier disruption. J Cell Sci 124(Pt 9):1486-95 |
abstractText | Previous studies have shown that plasmin cleaves monocyte chemoattractant protein 1 (MCP1; officially known as C-C motif chemokine 2, CCL2) at K104, and this cleavage enhances its chemotactic potency significantly. Accumulating evidence reveals that MCP1 also disrupts the integrity of the blood-brain barrier (BBB). Here, we show that K104Stop-MCP1, truncated at the K104 where plasmin would normally cleave, is more efficient than the full-length protein (FL-MCP1) in compromising the integrity of the BBB in in vitro and in vivo models. K104Stop-MCP1 increases the permeability of BBB in both wild-type mice and mice deficient for tissue plasminogen activator (tPA), which converts plasminogen into active plasmin, suggesting that plasmin-mediated truncation of MCP1 plays an important role in BBB compromise. Furthermore, we show that the mechanisms underlying MCP1-induced BBB disruption involve redistribution of tight junction proteins (occludin and ZO-1) and reorganization of the actin cytoskeleton. Finally, we show that the redistribution of ZO-1 is mediated by phosphorylation of ezrin-radixin-moesin (ERM) proteins. These findings identify plasmin as a key signaling molecule in the regulation of BBB integrity and suggest that plasmin inhibitors might be used to modulate diseases accompanied by BBB compromise. |