Based on the comprehensive antibody engineering platform established through years of experience, scientist from Creative Biolabs had successfully produced an important type Fab-scFv fusion protein (tribody) using well established methods. Tribodies are multifunctional recombinant antibody derivatives, which utilize the natural in vivo hetero dimerization of the heavy chain and light chain of a Fab fragment, and thus form a scaffold incorporated with scFv binding domains. The tribody enables the generation of various multi-specific antibody products.
In the design of a tribody, each chain can be extended preferably at the C-terminus with an additional scFv binder. The chains are co-produced in mammalian cells such as HEK293 and CHO, where the host-cell BiP chaperone drives the formation of the heavy chain-light chain heterodimers. These heterodimers are very stable (usually more stable than BiTEs and diabodies) with each of the binders retaining their specific affinities, higher affinity bivalent tribody and higher activatation of T cell proliferation and cytotoxicity in vivo.
Compared with other bispecific antibodies, tribodies have several advantages especially in therapeutic applications, their intermediate size (~100 kDa) between bispecific antibody fragments and IgG molecules translates into an ideal balance between tumor penetration and half-life; tribody molecules can be constructed using 3 distinct binders (tri-specific), 2 distinct binders with one in double copy (bivalent, bispecific), or three copies of the same binder (trivalent); tribodies have similar bio-distribution patterns to IgG formats and even exhibit higher tumor accumulation rates than IgG formats.
Our Fab-scFv (Tribody) Construction Services Including:
• Design of Fab-scFv Tribody
• Expression and Purification
• ELISA/ FACS/ Apoptosis Assay
• Scale Up Production