Inhibition of Pathologic Neovascularization Using Anti-Vegf Diabody

Background and aim: vascular endothelial growth factor (vegf) plays a crucial role in angiogenesis within solid cancers. nanobodies derived from camelidae are a novel class of nanometer-sized antibodies possessing unique properties. however, nanobodies have a very short half-life in vivo due to their small size. development of a bivalent nanobody is one way to overcome the half-life problem of nanobodies. the primary bioinformatics analysis and molecular docking were performed on recombinant diabody sequences.methods: two identical anti-vegf nanobodies were connected together using a hinge region of igg2c. the recombinant plasmid (phen6c-bivalent nanobodies) transferred into an e.coli wk6 cells and expression induced by 1 mm isopropyl β-d-1-thiogalactopyranoside (iptg). recombinant bivalent nanobodies purified using nickel affinity chromatography and their function was assessed using mtt, tube formation, and cell migration assay. the pharmacokinetic study was performed by intravenous (i.v.) injection of recombinant diabody to six-week-old c57bl/6 mice.results: recombinant diabody significantly inhibited proliferation, tube formation, and migration of human endothelial cells higher than nanobody. pharmacokinetic results showed a two-fold higher half-life of bivalent nanobodies in comparison with the monovalent nanobody.conclusion: results indicate the potential of recombinant anti-vegf bivalent nanobodies as a promising tool for development of a novel therapeutic with an extended half-life for the vegf-related disease.