Bevacizumab Revisited: Its Use in Different Mouse Models of Ocular Pathologies

ABSTRACT

Purpose: Previous reports have yielded conflicting data on the activity of bevacizumab (Avastin), a recombinant humanized monoclonal antibody against VEGF-A, in the mouse. The current study was designed to further explore the use of this VEGF inhibitor in various murine models of ocular diseases and compare it to the widely used murine anti-VEGF-R2 neutralizing antibody (DC101).

Methods: Murine models of laser-induced choroidal neovascularization (CNV), oxygen-induced retinopathy (OIR) and glaucoma filtration surgery (GFS) were used to investigate the effect of bevacizumab. Mice either received an intravitreal (CNV–OIR) or subconjunctival (GFS) injection. In all models, they were divided in two groups (n = 10 per group). In the first group, one eye was injected with bevacizumab (1 µl; 25 µg) and the other eye was used as a negative control and received an injection of NaCl (1 µl; 0.9%). In the second group, one eye was injected with DC101 (1 µl; 6.2 µg), whereas an isotype-matched control antibody (1C8; 4.8 µg) was administered in the contralateral eye. Treatment outcome was studied by clinical investigation (GFS) and immunohistological analysis of angiogenesis (CD31/FITC-dextran/H&E) and fibrosis (Sirius Red).

Results: Analysis of blood vessel density (CNV) and blood vessel growth (OIR) showed a comparable decrease after intravitreal administration of bevacizumab or DC101. Furthermore, in the mouse model of GFS, clinical investigation of the bleb and a CD31 staining on sections demonstrated that subconjunctival injection of both antibodies similarly improved the surgical outcome (bleb area and survival) by reducing angiogenesis. Moreover, morphometric analysis after Sirius Red staining showed a comparable reduction in collagen deposition after administration of the inhibitors.

Conclusion: Our findings consistently demonstrate that bevacizumab is as effective as the murine anti-VEGF-R2 antibody (DC101) in mouse models of CNV, OIR and GFS, thus confirming its suitability for translational ophthalmological research.

• Antivascular endothelial growth factor receptor 2
• bevacizumab
• choroidal neovascularization
• glaucoma filtration surgery
• oxygen-induced retinopathy

ACKNOWLEDGMENTS

The authors wish to thank Sofie Beckers, Ann Verbeek and Martine Leijssen for their technical support and Prof. Dr. Jaan Toelen for the use of the neonatal incubator. The authors are thankful to Amakem and ThromboGenics for the financial support. DC101 and 1C8 were kindly provided by ThromboGenics NV. Karolien Hollanders: financially supported by Amakem NV; Tine Van Bergen: financially supported by ThromboGenics NV via IWT Innovation fellowship; Sarah Van de Velde: financially supported by Amakem via IWT Baekeland fellowship; Davine Sijnave: financially supported by Amakem; Evelien Vandewalle: none; Lieve Moons: none; Ingeborg Stalmans: none.

DECLARATION OF INTEREST

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.