Mouse Bispecific Antibody Reagents Introduced

Absolute Antibody Ltd have announced the launch of the first commercially available mouse knob-into-hole (KIH) bispecific antibody reagents. Bispecific antibodies, which permit simultaneous engagement of two different protein targets, are an exciting new class of therapeutics, but many of the formats developed for human antibodies do not readily transfer to murine antibodies. These new murine bispecific reagents enable researchers and drug developers to more easily evaluate potential bispecific combinations in mouse models.

Absolute Antibody’s new bispecific antibodies are fully murine, meaning they can be used in vivo without rapidly inducing neutralising, anti-drug antibodies. In addition, the antibodies can be engineered with a silenced Fc domain when desirable for the biological activity of the bispecific, while still retaining FcRn-mediated recycling capabilities. All antibodies are produced recombinantly for ensured batch-to-batch reproducibility, and offer high purity and low endotoxin levels ideal for in vivo applications.

“Absolute Antibody is committed to creating a unique reagents catalogue through recombinant protein engineering approaches,” said Dr Michael Fiebig, Director of Products and Innovations at Absolute Antibody. “Our new knob-into-hole bispecific antibodies illustrate how we can take antibody engineering concepts developed for human therapeutics and apply them back to research reagents, thereby bringing the technology back into the lab and opening up exciting new research possibilities for the scientific community.”

Absolute Antibody has created mouse bispecific antibodies to target key proteins involved in different immunological pathways, including PD-L1, CD3ε and CD47. Researchers can also build their own custom bispecific reagent, selecting two targets to combine into one antibody reagent. Customers can then explore in mouse models how their selected targets might work in combination as a surrogate for a therapeutic bispecific antibody.

Absolute Antibody has grown rapidly since its founding in 2012, offering antibody sequencing, engineering and expression as custom services, as well as a catalogue of more than 3,800 engineered recombinant antibodies. In 2018, the company launched its first-generation murine bispecific antibodies in the IgG:dAb format, in a world-first for the reagents market. Now, its bispecific antibodies are available in the knob-into-hole format, using single-domain binders on one arm to overcome the light-chain pairing problem. This format can be expanded further in the future, allowing re-creation of the most commonly used formats in drug development and providing an important tool for the advancement of basic research and drug development alike.