cH IgG1 / κλ body

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 mAb species (one κ and one λ) and a BiAb containing a κ and λ light chain (Fig. 1.). A BiAb assembled in this manner can then be efficiently purified from the mAb species and other contaminants using highly selective affinity resins binding to either human κ or λ constant domains.  A κλ-body includes a common heavy chain and two light chains (one kappa and one lambda) with distinct specificities. Meanwhile, it is noteworthy that all of these fragments are integrated without any artificial mutations or linkers. Therefore, κλ-bodies with full human IgG backbone and intact Fc have got attractive characteristics including potent functions, extended half-life, long term storage, increased stability and ease of large-scale manufacturing. Thus, κλ-bodies are considered to be a leading one among our diverse products. Antibodies in this format are ideally suited for therapeutic application in both benign and malignant diseases.

Fig. 1. Schematic representation of the production of κλ body. Fig a illustrates the parallel discovery of two bispecific arms from a fixed VH library. Fig b illustrates the sequential discovery of a second arm compatible with an existing antibody.

Formats of bispecific antibodies (BsAbs)

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