title: Monoclonal antibody aggregation intermediates visualized by atomic force microscopy.
abstract: Ubiquitous but highly variable processes of therapeutic protein aggregation remain poorly characterized, especially in the context of common infusion reactions and clinical immunogenicity. Among the numerous challenges is the characterization of intermediate steps that lead to the appearance of precipitates. Although the biophysical methods for elucidation of secondary and tertiary structures as well as overall size distribution are typically well established in the development laboratories, the use of molecular scale imaging techniques is still relatively rare due to low throughput and technical complexity. In this work, we present the use of atomic force microscopy to examine morphology of monoclonal antibody aggregates. Despite varying in primary structure as a result of different complementarity defining regions, most antibodies studied exhibited a similar aggregation intermediate consisting of several monomers. However, the manner of subsequent condensation of these oligomers appeared to differ between the antibodies, suggesting stability-dependent mechanisms.
authors.affiliation: Merck Research Laboratories, West Point, Pennsylvania 19486, USA.
authors.forename: Hanjoo
authors.initials: H
authors.lastname: Lee
authors.forename: Marc
authors.initials: M
authors.lastname: Kirchmeier
authors.forename: Henryk
authors.initials: H
authors.lastname: Mach
mesh_terms: D006801:Humans; D007074:Immunoglobulin G / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D011487:Protein Conformation; D017510:Protein Folding
chemical_list: D007074:Immunoglobulin G