Intracellular bevacizumab reduces phagocytotic uptake in RPE cells

Abstract

Background: We have previously shown that bevacizumab, but not ranibizumab, is taken up by porcine RPE cells. In this study, the effects of bevacizumab and ranibizumab on proliferation, wound healing and phagocytosis of the RPE were investigated.

Methods: Primary porcine RPE cell culture were prepared from fresh eyes, cultivated and treated with clinically relevant concentrations of bevacizumab or ranibizumab respectively. Proliferation was investigated in a proliferation assay, wound healing in a wound scratch assay and phagocytosis was investigated by feeding RPE cells photoreceptor outer segment-opsonized FITC-labeled latex beads.

Results: Bevacizumab, and to a lesser extend ranibizumab, impair the proliferation of RPE cells but do not affect wound healing. Bevacizumab, but not ranibizumab, reduces the phagocytotic function of RPE cells.

Conclusions: The uptake of bevacizumab reduces phagocytosis in RPE cells, which indicates possible long-term effects of repeated bevacizumab treatment.