Surface plasmon resonance (SPR) and bio-layer interferometry (BLI) are label-free techniques which are used to investigate biomolecular interactions. They are especially suitable for characterizing antibody-antigen interactions and Fc-related antibody-effector interactions. In these techniques, the ligand is captured on the biosensor surface and binding of the analyte is investigated and information on the association and dissociation kinetics is obtained.
We provide SPR and BLI analyses to characterize protein-protein (e.g. antibody-antigen), antibody - FcRn and antibody - FcγR interactions. While measurements for ranking of antibody candidates can be done using single concentrations, determination of the kinetic parameters typically requires analysis using multiple concentrations. When investigating antibody - FcRn receptor interactions, the binding is studied at two different pH conditions, which are relevant for antibody recycling. For investigating FcRn interactions, receptors of various preclinical species and human are available. For FcγR-related interactions, we provide analysis of mAb binding affinity on human FcγRI, FcγRIIA (H/R131), FcγRIIB, FcγRIIIA (V/F158) and FcγRIIIB.