Abstract
Angiopoietin-2: Modulator of Vascular Permeability in Acute Lung Injury?
Highlights
Permeability in Acute Lung Injury?Tie (tyrosine kinase with immunoglobulin-like loop and epidermal growth factor homology domains) represents a novel class of receptor tyrosine kinases that are mostly expressed by vascular endothelial cells
The functional consequences of Ang/Tie2 signaling have been well established through genetic lossof-function and gain-of-function experiments in animals and cultured human endothelial cells
Ang1 signaling via Tie2 promotes vessel maturation and quiescence, whereas Ang2 blocks Ang1/Tie2 signaling, and this leads to either angiogenesis or vessel regression and apoptosis, depending on the presence of vascular endothelial growth factor (VEGF) or other angiogenic factors
Summary
Tie (tyrosine kinase with immunoglobulin-like loop and epidermal growth factor homology domains) represents a novel class of receptor tyrosine kinases that are mostly expressed by vascular endothelial cells. Endothelial cells express both Tie and Tie receptors. Tie is expressed in quiescent endothelial cells in adult tissues. The functional consequences of Ang/Tie signaling have been well established through genetic lossof-function and gain-of-function experiments in animals and cultured human endothelial cells. According to these functional studies, Ang is an agonist ligand that activates Tie, controlling endothelial cell survival and vessel maturation associated with the quiescent nonproliferating endothelial cell phenotype. Ang binds to the Tie receptor, but acts as a nonsignal-transducing Tie antagonist ligand that blocks Ang1/Tie signaling and acts as a blood vessel–destabilizing cytokine. High concentrations of Ang or prolonged exposure of endothelial cells to Ang have been shown to activate Tie signaling, the mechanisms of this paradoxical agonist activity of Ang are not well understood [1]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
