Analysis of recombinant monoclonal antibody isoforms by electrospray ionization mass spectrometry as a strategy for streamlining characterization of recombinant monoclonal antibody charge heterogeneity.
A therapeutic recombinant monoclonal antibody analyzed by cation-exchange chromatography exhibited a heterogeneous profile composed of approximately 10 isoforms. The peaks were isolated and characterized by electrospray quadrupole time-of-flight mass spectrometry (ESI-q-TOF-MS), N-terminal Edman sequencing, peptide mapping, and other techniques. Acidic (lower pI) peaks were found to represent deamidated and sialyated species. Higher pI peaks were found to contain N- and C-terminal heavy-chain variants. Biological activities of the more abundant isoforms were found to be comparable. An approach streamlining the characterization of antibody charge heterogeneity is proposed.
Lyubarskaya
Yelena
Y
Biogen Idec, Analytical Development, Cambridge, MA 02142, USA. yelena.lyubarskaya@biogenidec.com
Houde
Damian
D
Woodard
James
J
Murphy
David
D
Mhatre
Rohin
R
D000911:Antibodies, Monoclonal / Q000032:analysis*; D006801:Humans; D011134:Polysaccharides / Q000032:analysis; D020033:Protein Isoforms / Q000032:analysis; D011994:Recombinant Proteins / Q000032:analysis; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D000911:Antibodies, Monoclonal; D011134:Polysaccharides; D020033:Protein Isoforms; D011994:Recombinant Proteins