With Matt Iadanza, and colleagues from the Radford Lab here in Leeds, and MedImmune (Cambridge).
Uncontrolled self-association is a major challenge in the exploitation of proteins as therapeutics. Here we describe the development of a structural proteomics approach to identify the amino acids responsible for aberrant self-association of monoclonal antibodies and the design of a variant with reduced aggregation and increased serum persistence in vivo. We show that the human monoclonal antibody, MEDI1912, selected against nerve growth factor binds with picomolar a nity, but undergoes reversible self-association and has a poor pharmacokinetic pro le in both rat and cynomolgus monkeys. Using hydrogen/ deuterium exchange and cross-linking-mass spectrometry we map the residues responsible for self-association of MEDI1912 and show that disruption of the self-interaction interface by three mutations enhances its biophysical properties and serum persistence, whilst maintaining high a nity and potency. Immunohistochemistry suggests that this is achieved via reduction of non-speci c tissue binding. The strategy developed represents a powerful and generic approach to improve the properties of therapeutic proteins.