NKp46‐specific single domain antibodies enable facile engineering of various potent NK cell engager formats. (24th February 2023)

• Record Type: Journal Article
• Authors: Lipinski, Britta; Arras, Paul; Pekar, Lukas; Klewinghaus, Daniel; Boje, Ammelie Svea; Krah, Simon; Zimmermann, Jasmin; Klausz, Katja; Peipp, Matthias; Siegmund, Vanessa; Evers, Andreas; Zielonka, Stefan
• Is Part Of: Protein science. Volume 32:Number 3(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2023-02-24
• Subjects: ADCC -- antibody engineering -- bispecific antibody -- multifunctional antibody -- NK cell engager -- NK cell redirection -- NKp46 -- single domain antibody -- valencies -- VHH; Proteins -- Periodicals; 572.6
• DOI: 10.1002/pro.4593
• Languages: English
• ISSNs: 0961-8368

Abstract

Abstract: Herein, we describe the generation of potent NK cell engagers (NKCEs) based on single domain antibodies (sdAbs) specific for NKp46 harboring the humanized Fab version of Cetuximab for tumor targeting. After immunization of camelids, a plethora of different VHH domains were retrieved by yeast surface display. Upon reformatting into Fc effector‐silenced NKCEs targeting NKp46 and EGFR in a strictly monovalent fashion, the resulting bispecific antibodies elicited potent NK cell‐mediated killing of EGFR‐overexpressing tumor cells with potencies (EC50 killing) in the picomolar range. This was further augmented via co‐engagement of Fcγ receptor IIIa (FcγRIIIa). Importantly, NKp46‐specific sdAbs enabled the construction of various NKCE formats with different geometries and valencies which displayed favorable biophysical and biochemical properties without further optimization. By this means, killing capacities were further improved significantly. Hence, NKp46‐specific sdAbs are versatile building blocks for the construction of different NKCE formats.