title: Kinetics of Monoclonal Antibody Aggregation from Dilute toward Concentrated Conditions.
abstract: Gaining understanding on the aggregation behavior of proteins under concentrated conditions is of both fundamental and industrial relevance. Here, we study the aggregation kinetics of a model monoclonal antibody (mAb) under thermal stress over a wide range of protein concentrations in various buffer solutions. We follow experimentally the monomer depletion and the aggregate growth by size exclusion chromatography with inline light scattering. We describe the experimental results in the frame of a kinetic model based on population balance equations, which allows one to discriminate the contributions of the conformational and of the colloidal stabilities to the global aggregation rate. Finally, we propose an expression for the aggregation rate constant, which accounts for solution viscosity, protein-protein interactions, as well as aggregate compactness. All these effects can be quantified by light scattering techniques. It is found that the model describes well the experimental data under dilute conditions. Under concentrated conditions, good model predictions are obtained when the solution pH is far below the isoelectric point (pI) of the mAb. However, peculiar effects arise when the solution pH is increased toward the mAb pI, and possible explanations are discussed.
authors.affiliation: Department of Chemistry and Applied Biosciences, ETH Zurich , CH-8093 Zurich, Switzerland.
authors.forename: Lucrèce
authors.initials: L
authors.lastname: Nicoud
authors.affiliation: Department of Chemistry and Applied Biosciences, ETH Zurich , CH-8093 Zurich, Switzerland.
authors.forename: Jakub
authors.initials: J
authors.lastname: Jagielski
authors.affiliation: Department of Chemistry and Applied Biosciences, ETH Zurich , CH-8093 Zurich, Switzerland.
authors.forename: David
authors.initials: D
authors.lastname: Pfister
authors.affiliation: Department of Chemical Engineering, MIT , Cambridge, Massachusetts 02139, United States.
authors.forename: Stefano
authors.initials: S
authors.lastname: Lazzari
authors.affiliation: UCB Pharma, Braine l'Alleud, 1070 Anderlecht, Belgium.
authors.forename: Jan
authors.initials: J
authors.lastname: Massant
authors.affiliation: Adolphe Merkle Institute, University of Fribourg , 1700 Fribourg, Switzerland.
authors.forename: Marco
authors.initials: M
authors.lastname: Lattuada
authors.affiliation: Department of Chemistry and Applied Biosciences, ETH Zurich , CH-8093 Zurich, Switzerland.
authors.forename: Massimo
authors.initials: M
authors.lastname: Morbidelli
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry*; D002850:Chromatography, Gel; D000067493:Dynamic Light Scattering; D007074:Immunoglobulin G / Q000737:chemistry*; D007700:Kinetics; D066329:Protein Aggregates; D013696:Temperature; D014783:Viscosity
chemical_list: D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D066329:Protein Aggregates