FcRn Binding Assays

A key factor in the efficacy of therapeutic antibodies is the serum half-life and this is largely determined by the interaction between the antibody and the neonatal Fc receptor (FcRn); evaluation and understanding of your antibody product’s ability to bind FcRn can play a pivotal role in developing a safe and efficacious molecule.

The neonatal Fc Receptor (FcRn) is an MHC class-I-like molecule associated with beta-2-microglobulin and prevents the degradation of IgG, prolonging the half life in vivo. FcRn functions include the mediation of bidirectional transcytosis of IgG across cell membranes as well enhancement of IgG mediated phagocytosis and antigen presentation. The binding affinity of FcRn for IgG is negligible at physiological pH and the binding interaction can only occur following pincytosis within the early endosome; the IgG/FcRn complex can then be returned to the cell surface.

BioOutsource provides off-the-shelf FcRn binding assays by surface plasmon resonance (SPR) using the Biacore T200, which is a versatile, label-free system with exceptional sensitivity and as the most sensitive SPR instrument available from GE Healthcare, it provides the optimal platform for evaluation of IgG/FcRn binding interactions. We have extensive experience analyzing a range of biosimilar monoclonal antibodies with a variety of different IgG subtypes and can perform assays using relevant positive controls. Our FcRn binding assay services can be used to determine the Binding Affinity Constant (KD)

Our experience in the development and qualification of methods makes BioOutsource the perfect partner to support you as you progress through the clinical phases. We can support clone ranking and candidate selection studies, characterization and similarity studies.