Construction of Novel Bispecific Single-Domain Antibodies (BiSdAbs) with Potent Antiangiogenic Activities

Tianyuan Sun,Jianwei Zhu,Qiuhan Ge,Xianglei Liu

doi:10.1055/s-0040-1708527

Tianyuan Sun, Jianwei Zhu + Show 2 more

Open Access

https://doi.org/10.1055/s-0040-1708527

Copy DOI

Journal: Pharmaceutical Fronts	Publication Date: Mar 1, 2020
Citations: 3	License type: CC BY 4.0

Affiliation: Shanghai Jiao Tong University

Abstract

AbstractThe development of bispecific antibodies (BsAbs) has had a profound impact on cancer immunotherapy. Single-domain antibodies (SdAbs) could offer advantages over other antibody formats for the generation of a BsAbs, such as small size (∼12–15 kDa), with high affinity and specificity, superior accessibility, and high yield expression in bacteria. In this study, VEGFR2 and CD16 were chosen as the targets to construct BsAbs. As the rationale, VEGFR2 is critical for tumor-associated angiogenesis, and CD16 expressed on natural killer cells is an important target on immune cells. Humanized anti-VEGFR2 SdAb 3VGR19 and anti-CD16 SdAb C21 were combined to construct several bispecific SdAbs (BiSdAbs). The biochemical properties of the BiSdAbs were characterized. They retained the high affinity for both targets, binding selectivity, and antiangiogenic activity such as inhibition of cell proliferation, migration, endothelial tube formation, angiogenesis, and cytotoxicity to cancer cells in vitro, indicating that BiSdAbs could be a potential alternative for cancer therapy.

Highlights

Monoclonal antibody has been an ideal tool for targeted therapy.[1]
human umbilical vein endothelial cells (HUVECs) were grown in an endothelial cell medium (ECM, ScienCell) supplemented with 10% (v/v) FBS, 1% (v/v) endothelial cell growth supplement (ECGS), and 1% (v/v) P/S provided by the manufacturers
Vincke and collaborators described an universal humanized single-domain antibodies (SdAbs) scaffold in 2009, which allows grafts of antigenbinding loops from other SdAbs with transfer of the antigen specificity and affinity.[40]. This universal scaffold was used as the first humanization method, the complementarity-determining regions (CDRs) of the parental SdAbs 3VGR19, NTV1, and C21 were genetically grafted to h-NbBcII10(FGLA), and the candidates were named 3VGR19–1, NTV1–1, and C21–1, respectively

Summary

Introduction

Monoclonal antibody (mAb) has been an ideal tool for targeted therapy.[1] long-term efficacy of mAbs was limited by resistance mechanisms, such as tumors evaded immune control.[2] Bispecific antibodies (BsAbs), such as bispecific T-cell engager (BiTE),[3] dual affinity re-targeting (DART), knob-inhole, and bispecific antibody by protein trans-splicing (BAPTS),[4] can redirect the cytotoxic potential of immune cells to eliminate tumor cells with one arm directly engaging T cells and the other recognizing cancer cells. The wave of next-generation “bispecific or multispecific antibodies” has arrived.[10,11,12]

Methods

Results

Discussion

Conclusion