Glycosylation influences on the aggregation propensity of therapeutic monoclonal antibodies

Abstract

Monoclonal antibodies are the fastest growing class of biologics in the pharmaceutical industry. The correlation between mAb glycosylation and aggregation has not been elucidated in detail, yet understanding the structure-stability relationship involving glycosylation is critical for developing successful drug formulations. We conducted studies of temperature-induced aggregation and compared the stability of both glycosylated and aglycosylated forms of a human IgG1. In parallel, we also performed molecular dynamics simulations of the glycosylated full antibody to gain an understanding of the polysaccharide surroundings at the molecular level. Aglycosylated mAbs are somewhat less stable and therefore aggregate more easily than the glycosylated form at the temperatures studied. Glycosylation seems to enhance solubility and stability of these therapeutics and thus might be important for long-term storage.

Correlations between changes in conformational dynamics and physical stability in a mutant IgG1 mAb engineered for extended serum half-life

“…30 It is possible that the increased flexibility of the peptide backbone disrupts the packing interactions between the peptide backbone and the glycan chains, leading to unfolding of this hydrophobic segment. This unfolded apolar segment, in turn, may act as a hotspot for subsequent structural alterations that could lead to irreversible aggregation in IgG1 mAbs, [55][56][57] for example, as observed by SEC analysis in this study. Limiting the flexibility of this particular segment may therefore serve as a good indicator for designing mAbs (and mAbrelated products such as IgG-Fc, fusion proteins, or antibody drug conjugates) with higher thermostability and resistance to aggregation.…”

The impact of glycosylation on monoclonal antibody conformation and stability

“…The percentage of aggregates, fragments and monomers from SEC chromatograms are plotted separately in Figure 7A-C. Figure 7A shows that all three antibodies exhibit higher aggregation rates after deglycosylation. 30 also mentioned that many hydrophobic residues masked by carbohydrate were exposed after deglycosylation. Both reports used molecular dynamics simulations during their analysis and suggested that the hydrophobicity change in the CH 2 domain played an important role during aggregate formation.…”

Editorial: Breaking down the walls to achieve interdisciplinary science and engineering

“…After successful purification and formulation, the questions remains whether the protein has been brought into its most stable form: to address this issue, the group of Bernhard Trout reports a predictive tool to determine proteins stability [17], which follows on from their previous report of an algorithm that demonstrates to what extent glycosylation of antibodies influences their stability [18].…”