Abstract
Purpose::
To investigate the corneal biocompatibility of bevacizumab on various cultured human corneal cells.
Methods::
Cell cultures of corneal keratinocytes (CK), corneal fibroblasts (CF) and corneal endothelial cells (CEC) were harvested from human donor eyes and exposed to various concentrations of bevacizumab (0.08-2.5 mg/ml). Cell viability was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay at day 1 and 4 after exposure. For cytotoxicity testing confluent cells were cultured in serum depleted medium and the MTT test was performed after 24 hours of incubation. Expression of vascular endothelial growth factor (VEGF), VEGF-receptors (VEGFR1 and VEGFR2), keratan sulphate (KS) and cytokeratin-3 (AE5) was investigated by immunohistochemistry. Live/DeadTM Viability/Cytotoxicity assay was performed and analysed by fluorescence microscopy after 24 hours of incubation. Cell morphology was assessed with a phase contrast microscope after seven days of exposure with different concentrations of bevacizumab (0.008-2.5 mg/ml) and signs of cellular damage were assessed.
Results::
No cytotoxic effect of bevacizumab on CK, CF and CEC cells could be observed when used at a concentration of 2.5 mg/ml or lower. Bevacizumab-treated cells disclosed no signs of cellular damage when compared to the control. CK, CF and CEC cells stained positively for VEGF, VEGFR1 and VEGFR2. CK and CEC stained positively for AE5, whereas CF were immunpositive for KS.
Conclusions::
Bevacizumab is not toxic to corneal cells of human origin in vitro at doses ten fold higher than that used for intravitreal application in routine clinical practice.
Keywords: cornea: basic science • apoptosis/cell death • cornea: endothelium