Effects of Ranibizumab, Bevacizumab, Aflibercept and Ziv-aflibercept on Cultured Human Retinal Müller Cells

Abstract

 

Purpose

 

Anti-VEGF (vascular endothelial growth factor) therapy is the mainstay of treatment for neovascular age-related macular degeneration (AMD). However, it has been suggested that the chronic use of anti-VEGF may lead to geographic atrophy (GA). The development of GA may potentially be a manifestation of a subtle toxic effect of anti-VEGF on retinal cells, despite the overall net benefit of treatment. The MIO-M1 cell line is an immortalized culture of human Müller cells which give structural and metabolic support to retinal neurons and blood vessels. They are involved with retinal wound healing, neovascularization and retinal proliferative disorders; also association with AMD pathophysiology has been reported. The purpose of this study is to assess whether there is a measurable impact on cell viability in cultured MIO-M1 cells treated with one of four concentrations of ranibizumab, bevacizumab, aflibercept or ziv-aflibercept; and whether there are differences between the drugs in their effect on retinal cell viability.

 

Methods

 

MIO-M1 cells were cultured in DMEM 4.5g/L glucose with GlutaGRO and 10% fetal bovine serum. Cells were treated with either ranibizumab, bevacizumab, aflibercept or ziv-aflibercept at 1/2x, 1x, 2x or 10x the clinical concentration. After 24 hours, cell viability was assessed with the Vi-CELL trypan blue dye exclusion cell viability analyzer.

 

Results

 

For ranibizumab (Fig. 1a) and aflibercept (Fig. 1c) there were not any statistically significant reductions in cell viability for any concentration compared to untreated controls. Significant differences were found for bevacizumab (Fig. 1b) at the 10x concentration (91.58%, p<0.01), and ziv-aflibercept (Fig. 1d) at the 2x (94.6%, p<0.001) and 10x (89.8%, p<0.001) concentrations compared to untreated samples.

 

Conclusions

 

Ranibizumab and aflibercept were found not to decrease cell viability in cultured Müller cells at all the concentrations studied. The clinical dose (1x) and twice the clinical dose (2x) of bevacizumab similarly showed no significant decrease in cell viability on MIO-M1 cells in vitro. Ziv-aflibercept was not detrimental to cell viability at low dose (1/2x) and clinical-equivalent dose (1x) for MIO-M1 cells in vitro. However twice the clinical dose of ziv-aflibercept did reduce Müller cell viability, whereas this reduction at 2x clinical dose was not observed for ranibizumab, aflibercept, or bevacizumab.

 

 

 

Keywords: 748 vascular endothelial growth factor • 603 Muller cells • 412 age-related macular degeneration