Autor: |
Mozziconacci O; Merck & Co., Inc., Rahway, New Jersey 07065, United States., Subelzu N; Department of Pharmaceutical Chemistry, The University of Kansas, Lawrence, Kansas 66047, United States., Schöneich C; Department of Pharmaceutical Chemistry, The University of Kansas, Lawrence, Kansas 66047, United States., Liu Y; Merck & Co., Inc., Rahway, New Jersey 07065, United States., Abend A; Merck & Co., Inc., Rahway, New Jersey 07065, United States., Wuelfing WP; Merck & Co., Inc., Rahway, New Jersey 07065, United States. |
Abstrakt: |
This work demonstrates the use of a fluorescent probe to screen protein conformational changes in mixtures of monoclonal antibodies and determine the region of where such changes may originate through a footprinting mass spectrometry approach. The oxidative stress of mixtures of two different immunoglobulins (IgG1, IgG2, or IgG4) performed in the presence of 2,2'-azobis(2-amidinopropane dihydrochloride) results in sequence-specific tyrosine oxidation reactions depending on the time of incubation of the IgG molecules and the nature of the excipients present in the formulation. The combination of a fluorescence assay, based on the detection of 3,4-dihydroxyphenylalanine (DOPA) and mass spectrometry analyses, permits the identification of protein conformation changes. In a mixture of IgG2 and IgG4, a destabilization of IgG4 in the presence of IgG2 is observed. The destabilized region involves the Fab region of IgG4 between Tyr63 and Tyr81 and potentially multiple regions of IgG2. |