First Author | van den Berg YW | Year | 2009 |
Journal | Proc Natl Acad Sci U S A | Volume | 106 |
Issue | 46 | Pages | 19497-502 |
PubMed ID | 19875693 | Mgi Jnum | J:154772 |
Mgi Id | MGI:4398792 | Doi | 10.1073/pnas.0905325106 |
Citation | van den Berg YW, et al. (2009) Alternatively spliced tissue factor induces angiogenesis through integrin ligation. Proc Natl Acad Sci U S A 106(46):19497-502 |
abstractText | The initiator of coagulation, full-length tissue factor (flTF), in complex with factor VIIa, influences angiogenesis through PAR-2. Recently, an alternatively spliced variant of TF (asTF) was discovered, in which part of the TF extracellular domain, the transmembrane, and cytoplasmic domains are replaced by a unique C terminus. Subcutaneous tumors produced by asTF-secreting cells revealed increased angiogenesis, but it remained unclear if and how angiogenesis is regulated by asTF. Here, we show that asTF enhances angiogenesis in matrigel plugs in mice, whereas a soluble form of flTF only modestly enhances angiogenesis. asTF dose-dependently upregulates angiogenesis ex vivo independent of either PAR-2 or VIIa. Rather, asTF was found to ligate integrins, resulting in downstream signaling. asTF-alphaVbeta3 integrin interaction induces endothelial cell migration, whereas asTF-dependent formation of capillaries in vitro is dependent on alpha6beta1 integrin. Finally, asTF-dependent aortic sprouting is sensitive to beta1 and beta3 integrin blockade and a TF-antibody that disrupts asTF-integrin interaction. We conclude that asTF, unlike flTF, does not affect angiogenesis via PAR-dependent pathways but relies on integrin ligation. These findings indicate that asTF may serve as a target to prevent pathological angiogenesis. |