First Author | Kesler CT | Year | 2015 |
Journal | FASEB J | Volume | 29 |
Issue | 9 | Pages | 3668-77 |
PubMed ID | 25977256 | Mgi Jnum | J:225538 |
Mgi Id | MGI:5693481 | Doi | 10.1096/fj.14-268920 |
Citation | Kesler CT, et al. (2015) Angiopoietin-4 increases permeability of blood vessels and promotes lymphatic dilation. FASEB J 29(9):3668-77 |
abstractText | The angiopoietin (Ang) ligands are potential therapeutic targets for lymphatic related diseases, which include lymphedema and cancer. Ang-1 and Ang-2 functions are established, but those of Ang-4 are poorly understood. We used intravital fluorescence microscopy to characterize Ang-4 actions on T241 murine fibrosarcoma-associated vessels in mice. The diameters of lymphatic vessels draining Ang-4- or VEGF-C (positive control)-expressing tumors increased to 123 and 135 mum, respectively, and parental, mock-transduced (negative controls) and tumors expressing Ang-1 or Ang-2 remained at baseline ( approximately 60 mum). Ang-4 decreased human dermal lymphatic endothelial cell (LEC) monolayer permeability by 27% while increasing human dermal blood endothelial cell (BEC) monolayer permeability by 200%. In vivo, Ang-4 stimulated a 4.5-fold increase in tumor-associated blood vessel permeability compared with control when measured using intravital quantitative multiphoton microscopy. Ang-4 activated receptor signaling in both LECs and BECs, evidenced by tyrosine kinase with Ig and endothelial growth factor homology domains-2 (TIE2) receptor, protein kinase B, and Erk1,2 phosphorylation detectable by immunoblotting. These data suggest that Ang-4 actions are mediated through cell-type-specific networks and that lymphatic vessel dilation occurs secondarily to increased vascular leakage. Ang-4 also promoted survival of LECs. Thus, blocking Ang-4 may prune the draining lymphatic vasculature and decrease interstitial fluid pressure (IFP) by reducing vascular permeability.-Kesler, C. T., Pereira, E. R., Cui, C. H., Nelson, G. M., Masuck, D. J., Baish, J. W., Padera, T. P. Angiopoietin-4 increases permeability of blood vessels and promotes lymphatic dilation. |