Abstract 3836: Discovery of a highly potent fully human VEGF nanobody from RenNano transgenic mice that exhibits a superior blocking activity on VEGF function

Abstract Background: VEGFA (or VEGF hereafter) is the prototypic member of a family that also includes placental growth factor (PLGF, also known as PGF),VEGFB,VEGFC,VEGFD . VEGFR2 is the major mediator of the physiological and pathological effects of VEGF. VEGFR2 mediates EC proliferation, migration and arterial fate specification [1]. VEGFA monoclonal antibodies have significant therapeutic effects in the treatment of tumors and macular degeneration [2]. In this study, we evaluated a fully human anti-VEGFA mAb generated from our fully human antibody RenNanoTM mice. Methods: Blocking activity of the anti-VEGFA mAb against VEGF/VEGFR2 interaction was assessed using ELISA. The affinity to human VEGFA165 was measured by surface plasmon resonance (SPR). At the same time, we conducted relevant physicochemical property tests on the obtained nanobodies, including purity, Tm value, Tagg, and hydrophobicity assessment. To evaluate the in vitro inhibitory effect of anti-VEGFA on endothelial cell proliferation, we used human umbilical vein endothelial cells (HUVEC) for the experiment. Results: We identified an anti-VEGFA nano-antibody with high affinity to human VEGFA165,and it was able to block the interaction of VEGFA and VEGFR2 in vitro. Our antibody molecule exhibits desirable physicochemical properties, as we found that the purity is above 95% after one step of affinity chromatography. Furthermore, our anti-VEGFA nano-antibody exhibited a strong inhibitory activity on the proliferation of HUVEC cells compared to Bevacizumab analog. Citation Format: Yi Yang, Weiqiu Lan, Baihong Liu, Yang Chen. Discovery of a highly potent fully human VEGF nanobody from RenNano transgenic mice that exhibits a superior blocking activity on VEGF function [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 3836.