Format of bispecific antibodies (BsAbs)-VH-1-TCR C¦Á x VL-1-TCR C¦Â; VH-2-CH-2-Fc x VL-2-CL-2


WuXiBody, replace one parental mAb’s CH1/CL region by the T cell receptor (TCR) constant domain. WuXiBody’s design ensures cognate HC-LC pairing, the same goal as that being aimed by the CrossMab technology. BsAbs based on WuXiBody can adopt either asymmetric or symmetric format (Fig. 1). For asymmetric WuXiBody-based bsAbs, heterodimerization is promoted by the KiH technology. The TCR constant domain has a relatively low isoelectric point (pI) and consequently the target bsAb containing it also has a pI much lower than that of regular mAbs. In the case of asymmetric bsAbs, this feature promotes the use of ion exchange (IEX) chromatography to separate the target bsAb from potential non-TCR-containing byproducts (e.g., one type of half antibody and homodimer). Thus, introduction of TCR constant domain into WuXiBody construction not only promotes desired chain pairing but also facilitates removal of product-related impurities. Four WuXiBody-based bsAbs with different formats (two asymmetric and two symmetric ones) are show in Fig. 1.

Fig. 1. Schematic representation of four selected WuXiBody-based bsAbs (Adopted from: Guo, G., Han, J., Wang, Y., Li, Y. (2020) A potential downstream platform approach for WuXiBody-based IgG-like bispecific antibodies. Protein Expression and Purification. 173: 105647).

Formats of bispecific antibodies (BsAbs)

Many formats have been developed for BsAb generation as listed in the following table.

FormatSchematic structureDescriptionExample BsAbTrademark Company
tandem VHHTandem VHH fragment-based BsAbN/A
tandem scFvPicture loading failed.Tandem ScFv fragment-based BsAbAMG330BiTETMAmgen
Dual-affinity re-targeting antibodyPicture loading failed.Tandem domain-exchanged Fv (can also be used to fuse with Fc domain to create whole Abs)FlotetuzumabDARTTMMacrogenics
DiabodyPicture loading failed.dimer of single-chain Fv (scFv) fragmentvixtimotamabReSTORETMAmphivena Therapeutics
(scFv)2-FabPicture loading failed.a Fab domain and two scFv domains bindA-337ITabTMGeneron/EVIVE Biotech
Rat–mouse hybrid IgGPicture loading failed.Full-size IgG-like half antibodies from two different speciesCatumaxomabTriomabTMTrion Pharma
Hetero heavy chain, Common light chainPicture loading failed.Hetero heavy chain, Common light chainEmicizumabART-IgTMGenentech/ Chugai/Roche
Controlled Fab arm exchangePicture loading failed.Recombin the parental half antibodies JNJ-64007957DuobodyTMGenmab/ Janssen
Hetero H, forced HL IgG1Picture loading failed.KIH technology for heterodimerization of 2 distinct H chains, replacing the native disulfide bond in one of the CH1-CL interfaces with an engineered disulfide bond to enhance the cognate of H and L paringMEDI5752DuetMabTMMedImmune/ AstraZeneca
cH IgG1Picture loading failed.Identical heavy chains; 2 different light chains: one kappa (κ) and one lambda (λ)NI-1701κλ bodyTMNovimmune SA
Hetero H, CrossMabPicture loading failed.KIH technology; domain crossover of immunoglobulin domains in the Fab regionVanucizumabCrossMabTMRoche
scFv-Fab IgGPicture loading failed.Fab-Fc; ScFv-FcVibecotamab;
XmabTM (the engineered Fc to enhance the generation of heterodimeric Fc);
Xencor/Amgen; YZYBio
VH1-VH2-CH1-Fc1(G1) x VL2-VL1-CL-Fc2(G1)Picture loading failed.2 binding motif in one half antibodySAR440234CODV-IgTMSanofi
VL1-CL1-VH2-CH2-Fc x VH1-CH1 x VL2-CL2Picture loading failed.2 binding motif in one half antibodyEMB-01FIT-IgTMEPIMAB BIOTHERAPEUTICS
VH-1-TCR Cα x VL-1-TCR Cβ; VH-2-CH-2-Fc x VL-2-CL-2Picture loading failed.KIH technology; TCR Cα/Cβ is used to substitute the CH1 and CL domain in one armWuXibodyTMWuXi Biologics
C-terminal linker of FcPicture loading failed.Link the other molecules at the C-terminal of FcAPVO442ADAPTIR-FLEXTMAptevo Therapeutics
Fc antigen binding sitePicture loading failed.2 natural binding sites; 2 additional binding sites in the Fc loopFS118mAb2F-star Therapeutics