Pharmaceutical Research

, Volume 26, Issue 4, pp 903–913

Effect of Ions on Agitation- and Temperature-Induced Aggregation Reactions of Antibodies

Authors

  • R. Matthew Fesinmeyer
    • Department of Process and Product Development
  • Sabine Hogan
    • Department of Process and Product Development
  • Atul Saluja
    • Department of Process and Product Development
  • Stephen R. Brych
    • Department of Process and Product Development
  • Eva Kras
    • Department of Process and Product Development
  • Linda O. Narhi
    • Department of Process and Product Development
  • David N. Brems
    • Department of Process and Product Development
    • Department of Process and Product Development
Research Paper

DOI: 10.1007/s11095-008-9792-z

Cite this article as:
Fesinmeyer, R.M., Hogan, S., Saluja, A. et al. Pharm Res (2009) 26: 903. doi:10.1007/s11095-008-9792-z

Abstract

Purpose

The impact of ions on protein aggregation remains poorly understood. We explored the role of ionic strength and ion identity on the temperature- and agitation-induced aggregation of antibodies.

Methods

Stability studies were used to determine the influence of monovalent Hofmeister anions and cations on aggregation propensity of three IgG2 mAbs. The CH2 domain melting temperature (Tm1) and reduced valence (z*) of the mAbs were measured.

Results

Agitation led to increased solution turbidity, consistent with the formation of insoluble aggregates, while soluble aggregates were formed during high temperature storage. The degree of aggregation increased with anion size (F < Cl < Br < I < SCN ~ ClO4) and correlated with a decrease in Tm1 and z*. The aggregation propensity induced by the anions increased with the chaotropic nature of anion. The cation identity (Li+, Na+, K+, Rb+, or Cs+) had no effect on Tm1, z* or aggregation upon agitation.

Conclusions

The results indicate that anion binding mediates aggregation by lowering mAb conformational stability and reduced valence. Our observations support an agitation-induced particulation model in which anions enhance the partitioning and unfolding of mAbs at the air/water interface. Aggregation predominantly occurs at this interface; refreshing of the surface during agitation releases the insoluble aggregates into bulk solution.

KEY WORDS

aggregationHofmeister effectionsmonoclonal antibodyreduced valence

Copyright information

© Springer Science+Business Media, LLC 2008