Identification and Quantification of Signal Peptide Variants in an IgG1 Monoclonal Antibody Produced in Mammalian Cell Lines

Publication date: Available online 12 October 2017 Source:Journal of Chromatography B Author(s): Yunping Huang, Jinmei Fu, Richard Ludwig, Li Tao, Jacob Bongers, Li Ma, Ming Yao, Mingshe Zhu, Tapan Das, Reb Russell …

Publication date: Available online 12 October 2017
Source:Journal of Chromatography B

Author(s): Yunping Huang, Jinmei Fu, Richard Ludwig, Li Tao, Jacob Bongers, Li Ma, Ming Yao, Mingshe Zhu, Tapan Das, Reb Russell

Sequence variants of a monoclonal antibody resulting from incomplete processing of signal peptide were identified and characterized using multiple mass spectrometry platforms and reverse phase chromatography. Detection and quantification of these variants by three LC/MS platforms were assessed. Quantification was also performed by mass spectrometric analysis of the subunits of the antibody generated by reduction and IdeS proteolysis. Peptide mapping with LC/MS/MS detection was used to quantify and confirm the identities of signal peptide sequence variants. Although quantification of the signal peptide variants thru mass spectrometry approaches is system dependent, our data revealed the results are close to the values determined by chromatographic separation with UV detection. Each of the methods have proven effective in demonstrating the consistency of signal peptide variants levels across the manufacture history of the antibody.