September 2016
Volume 57, Issue 12
Open Access
ARVO Annual Meeting Abstract  |   September 2016
Barrier function studies of VEGF and ANG-2 in human endothelial cells
Author Affiliations & Notes
  • Guido Hartmann
    Roche Innovation Center Basel, Hoffman La Roche , Basel, Switzerland
  • Footnotes
    Commercial Relationships   Guido Hartmann, Hoffman La Roche (E)
  • Footnotes
    Support  None
Investigative Ophthalmology & Visual Science September 2016, Vol.57, 3217. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to Subscribers Only
      Sign In or Create an Account ×
    • Get Citation

      Guido Hartmann; Barrier function studies of VEGF and ANG-2 in human endothelial cells. Invest. Ophthalmol. Vis. Sci. 2016;57(12):3217.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose : Breakdown of the endothelial blood retinal barrier is key to pathophysiological changes in age-related macular degeneration and diabetic macular edema. VEGF-A (Vascular Endothelial Growth Factor-A) is involved in mediating breakdown of the endothelial barrier resulting in enhanced vascular leakage and subsequent edema in retinal tissue. Angiopoietins (ANG-1 and ANG-2) also modulate endothelial barrier function. We investigated a cellular model of endothelial barrier breakdown in vitro. VEGF-A, ANG-1 and ANG-2 and their respective neutralizing reagents were tested for the modulation of vascular barrier function.

Methods : Microvascular endothelial cells were cultured on transwell filters and stimulated with VEGF-A and/or ANG-1/ANG-2 in the presence and absence of neutralizing antibodies to VEGF-A and ANG-2. Measurement of transendothelial resistance (TEER) was followed by immunostainings for key molecules of adherens junctions and tight junctions. Immunocytochemistry was used to determine the expression of endothelial cell junctional proteins (VE-cadherin, a key component of endothelial cell-to-cell adherens junctions, ZO-1 adapter molecule, a component of tight junctions and the adhesion molecule PECAM-1).

Results : VEGF-A induced a dose dependent break down of barrier function in human microvascular cells. This effect was inhibited with an anti-VEGF antibody given preventative or interventative. ANG-1 increased barrier function as demonstrated by increased TEER values. Simultaneous incubation of VEGF-A and ANG-1 resulted in reduced barrier breakdown by VEGF-A. Endothelial cells in culture constitutively secrete high levels of ANG-2. Stimulation with VEGF-A enhanced this secretion further. Addition of neutralizing anti-ANG2 antibody reduced VEGF-A induced barrier breakdown while combined addition of ANG-1 and anti-ANG-2 was most efficacious. Distortion of the typical cell-cell boundary of VE-cadherin, ZO-1 and PECAM-1 was demonstrated when cells were treated with VEGF-A and prevented by coincubation with ANG1 and ANG1/anti-VEGF-A.

Conclusions : VEGF-A is a well-known inducer of barrier breakdown of endothelial cells. We describe in vitro experiments of endothelial barrier breakdown induced by VEGF-A and modulation by ANG-1 and anti-ANG-2. Combined inhibition of VEGF-A and ANG-2 might be an promising approach to enhance the efficacy of anti-VEGF-A treatments.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×