Resumen:
Purpose: Age-related macular degeneration (AMD) is the leading cause of blindness in developed countries. Controversy exists regarding the safety of agents that inhibit vascular endothelial growth factor (VEGF). In this study we performed different assays to compare in vitro cytotoxicity of bevacizumab (B), ranibizumab (R), and aflibercept (A) at clinical doses on retinal pigment epithelia (RPE) cell line (ARPE19).
Methods: Cellular toxicity was assessed through MTT cell viability and BrdU proliferation assays after single or repeated doses of the anti-VEGF drugs. Immunofluorescence (IF) for zonula ocludens (ZO-1) was performed. Intracellular accumulation was determined by IF (antihuman Cy3) one and five days after treatment with B, R and A. IF was also used to determine the activity of caspase-3 after single or repeated doses of B, R and A. The effect of anti-VEGF agents on cell phagocytosis of fluorescent latex beads was also assessed. Finally, RPE permeability 24, 48 and 72 hours after anti-VEGF treatments was studied using a FITC permeability assay on transwell inserts. Statistical analysis was performed (SPSS 20).
Results: There were no statistically significant differences in cell viability or cell proliferation after single or repeated doses of B, R and A. The tight junction labeled with ZO-1 was not altered with treatments. On the contrary, intracellular accumulation of R was significantly lower compared to the other anti-VEGF agents up to 5 days after initial treatment. Phagocytosis was significantly lower in cells treated with R and A (34% and 28.8%, p<0.001) compared to the control group, but not statistically significant in cells treated with B (75%, p=0.104). We found no significant differences in caspase-3 activity between the 3 drugs neither 24 hours nor one week after treatment. The anti-VEGF agents did not affect FITC permeability when compared to the control group at any time points.
Conclusions: Our results suggest that ranibizumab is the anti-VEGF agent that accumulates intracellularly to a lesser extent. However this finding does not affect in vitro cell viability and proliferation in the short time. Furthermore, we did not find a significant effect in cell death, cellular permeability or phagocytosis after single or repeated doses of the treatments. These results imply that anti-VEGF agents at clinical doses are safe in ARPE19 cells.
