Production and characterization of a novel site-specific-modifiable anti-OX40-receptor single-chain variable fragment for targeted drug delivery

• Published in: Biochemical and biophysical research communications Vol. 496; no. 2; pp. 614 - 620
• Main Authors: Tanabe, Aki, Nakano, Kazumi, Nakakido, Makoto, Nagatoishi, Satoru, Tanaka, Yuetsu, Tsumoto, Kouhei, Uchimaru, Kaoru, Watanabe, Toshiki
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 05.02.2018
• Subjects: Antibody drug conjugate; Drug delivery; Internalization; OX40; Single chain antibody(scFv); Thermal stability of antibody; OX40; scFvC; CD; TNFα; NFκB; OX40L; IgG; Drug delivery; Antibody drug conjugate; IκB; Single chain antibody(scFv); SDS-PAGE; SPR; PI3K; scFv; DSC; Internalization; Thermal stability of antibody
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2018.01.051

OX40 receptor (tumor necrosis factor receptor superfamily, member 4; CD134) is a T-cell co-stimulatory molecule that plays an important role in T-cell activation and survival. OX40 receptor is activated by its ligand, OX40L; and modulation of the OX40–OX40L interaction is a promising target for the treatment of autoimmune diseases and cancers. Here, we generated a high-affinity anti-OX40 single-chain variable fragment carrying a C-terminal cysteine residue (scFvC). Physicochemical and functional analyses revealed that the scFvC bound to OX40-expressing cells and was internalized via OX40-mediated endocytosis without inducing phosphorylation of IκBα (nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha), an important complex in the classical NFκB (nuclear factor kappa-light-chain-enhancer of activated B cells) signaling pathway. In addition, mutation of the 36th cysteine residue in variable region of light chain enabled site-specific chemical modification to carboxy terminal cysteine and improved the thermal stability of the scFvC. These results suggest that this novel high-affinity anti-OX40 scFvC may be useful as a transporter for targeted delivery of small compounds, proteins, peptides, liposomes, and nanoparticles, into OX40-expressing cells for the treatment of autoimmune diseases and cancers. •A novel high-affinity anti-OX40 scFv with a C-terminal cysteine (scFvC) was generated.•The scFvC retained high binding affinity regardless of fluorescence modifications.•A cysteine mutation (LC36) enabled scFvC to improve the thermal stability.•scFvC and LC36 mutants internalized into the target cells without activation of classical NFκB pathway.•Anti-OX40 scFvC and LC36 mutants may be useful as a carrier for drug delivery.