Category Archives: Biologics

Format of bispecific antibodies (BsAbs)-Rat-mouse hybrid IgG

Rat-mouse hybrid IgG is a monoclonal antibody with binding sites for two different antigens, typically CD3 and a tumor antigen, making it a type of bispecific monoclonal antibody. In addition, its intact Fc-part can bind to an fc receptor on accessory cells like conventional monospecific antibodies. The net effect is that this type of drug […]

Format of bispecific antibodies (BsAbs)-(scFv)2-Fab

Tribodies are multifunctional recombinant antibody derivatives. The Fab fragment serves as a specific heterodimerization signal, and the two scFv fragments are each fused to a different Fab chain. In this way we obtain a molecule of intermediate molecular weight (100 kDa) which allows incorporating three different antibody fragments (Fig. 1). This manifold, tribody, can be […]

Format of bispecific antibodies (BsAbs)-Diabody

Diabody is a noncovalent dimer of single-chain Fv (scFv) fragment that consists of the heavy chain variable (VH) and light chain variable (VL) regions connected by a small peptide linker. Another form of diabody is single-chain (Fv)2 in which two scFv fragments are covalently linked to each other. bispecific bivalent dimers are produced by using two […]

Format of bispecific antibodies (BsAbs)-Dual-affinity re-targeting antibody

Dual-affinity re-targeting proteins (DARTs) encompasses of two Fv fragments, containing two single antigen-binding sites formed when two Fv fragments heterodimerize. The Fv1 contains of a VH from antibody A and a VL from antibody B, whereas Fv2 contains VH from antibody B and VL from antibody A in the order of VL (1)-VH (2) and […]

Format of bispecific antibodies (BsAbs)-Tandem scFv

A tandem scFv links two or more scFvs with the helical peptide linkers in the orientation NH2–VL1–VH1–(linker–VL2–VH2)n–COOH, resulting in a single chain bivalent and bi-specific molecule encoded by a single gene (Figure 2). Tandem scFv can be used to target two different antigens on two different cells, two different antigens on the same cell, or […]

Format of bispecific antibodies (BsAbs)-Tandem VHH

Since 1975, monoclonal antibodies have been successfully used for the diagnosis and therapeutics. In 1993, heavy-chain-only antibodies which bind to antigens was discovered in camelids. The variable domain of heavy chain antibody (VHH) was called as nanobodies and it was anticipated as the better therapeutic antibodies in future due to its high stability, refoldability, and manipulable characteristics. […]

Format of bispecific antibodies (BsAbs)-Hetero H, CrossMab

CrossMab technology enforces correct light chain association based on the domain crossover of immunoglobulin domains in the Fab region of the bispecific antibody. CrossMab technology allow the generation of various bispecific antibody formats, including bi- (1+1), tri- (2+1) and tetra-(2+2) valent bispecific antibodies, as well as non-Fc tandem antigen-binding fragment (Fab)-based antibodies. These formats may […]

Format of bispecific antibodies (BsAbs)-cH IgG1

cH IgG1 / κλ body involves the formation of in vitro display libraries with common heavy chains against two different antigens. κλ body share the same heavy chain but carry either κ or λ light chains. Three different chains (one heavy and two light) are then co-expressed in a single cell to generate a mixture containing two […]

Format of bispecific antibodies (BsAbs)-Hetero H, forced HL IgG1

Hetero H, forced HL IgG1/ DuetMab replaces the native disulfide bond in the CH1-CL interface with an engineered disulfide bond (fig. 1). This enhances cognate light chain pairing. Three different positions in the CH1-CL interface are possible candidates for favoring the formation of a novel disulfide bond. An amino acid on the HC and one […]

Tandem VHH/Nanobody (single domain antibody) – Introduction

Since 1975, monoclonal antibodies have been successfully used for the diagnosis and therapeutics. In 1993, heavy-chain-only antibodies which bind to antigens was discovered in camelids. The variable domain of heavy chain antibody (VHH) was called as nanobodies and it was anticipated as the better therapeutic antibodies in future due to its high stability, refoldability, and manipulable characteristics. […]