Affinity Capillary Electrophoresis–Mass Spectrometry as a Tool to Unravel Proteoform-Specific Antibody–Receptor Interactions
Christoph Gstöttner, Michaela Hook, Tony Christopeit, Alexander Knaupp, Tilman Schlothauer, Dietmar Reusch, Markus Haberger, Manfred Wuhrer, Elena Domínguez‐Vega
Abstract
values in solution resulting in values of 422 and 139 nM for double-oxidized and non-oxidized variants. Hyphenation with native MS provides unique capabilities for simultaneous heterogeneity assessment for mAbs, FcRn, and complexes formed. The latter provides information on binding stoichiometry revealing 1:1 and 1:2 for antibody/FcRn complexes. The use of differently engineered Fc-only constructs allowed distinguishing between symmetric and asymmetric binding. The approach opens up unique possibilities for proteoform-resolved antibody binding studies to FcRn and can be extended to other FcRs and protein interactions.