Festival of Biologics – Basel 2024
Conference dates: October 15-17, 2024
Booth: 910
Location: Hall 1, Messe Basel, Basel, Switzerland
Poster session
Poster: HT-SPR Evaluation of Fc Gamma Receptor Binding using Carterra LSAXT
Poster number: 18
Poster Session: Day 2, 18:10
Presenter: Judicaël Parisot, PhD, Applications Science Team Lead – Europe , Carterra
Abstract: Fc gamma receptors (FcγRs) are a family of proteins expressed on the surface of immune cells that can elicit activating or inhibitory responses when bound by the Fc domain of IgG antibodies. IgG Fc-containing biologics are a substantial and growing class of drugs with over 175+ antibody therapeutics already approved or undergoing regulatory review (The Antibody Society, 2023). These biologics include IgG-based mAbs, multispecific antibodies, and Fc-fusion proteins. The Fc domain can be mutated to improve, diminish, or abrogate FcγR binding. It can also be mutated to heterodimerize Fc chains for multispecific antibody construction or to extend FcRn mediated half-life, to name a few common mutational strategies. In each application, assessing the mutational impact on each FcγR interaction relative to the wild-type Fc is critical as they are all bound by a common site in the hinge region of the Fc domain and can impart different FcγR-mediated immune responses as a function of their affinity. It is also critical to assess the binding of wild-type and engineered Fc domains to relevant species FcγRs if the therapeutic is intended to be administered to the respective species for proper drug characterization and data interpretation across species. FcγR affinities are commonly measured using lower throughput, high sensitivity biosensing instruments to accurately characterize these interactions and require significant lab time, instrument usage, and protein. Pairing Carterra’s LSAXT with ACROBiosystems’ proteins enables the development of a high-throughput assessment of FcγRs to simplify the characterization of IgG-Fc containing biologics. Herein, we detail a workflow utilizing High-Throughput SPR (HT-SPR) on the LSAXT to characterize trastuzumab (IgG1 mAb) against 11 FcγRs with high sensitivity and reproducibility in a fraction of the time and resources.