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PubMed · 9921157

Variant antibody identification by peptide mapping.

M Wan·F Y Shiau·W Gordon·G Y Wang
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Abstract

During development of CGP56901, a monoclonal antibody (MAb) specific for a unique epitope on human IgE, the protein A-purified IgG from one of the candidate production cell lines, showed an additional minor heavy chain (H-chain) band with a molecular weight slightly lower than that of the principal H-chain band on SDS-PAGE. The N-terminal amino acid sequence of this minor H-chain species indicated that at least the first 30 amino acids were identical to those of the antibody light-chain (L-chain) variable domain. More detailed studies using peptide mapping and amino acid sequencing analysis confirmed a crossover event between the V genes of the antibody. The position is between Arg108 of the L chain and Ala124 of the H chain. This crossover resulted in a variant H chain, which had 16 fewer amino acid residues than the normal CGP56901 H chain. These results show that peptide mapping is a useful "first-line" analytical tool in the characterization of the quality of the monoclonal antibody.

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Amino Acid SequenceAntibodies, MonoclonalBase SequenceBiotechnologyCrossing Over, GeneticDNA, ComplementaryGenetic VariationHumansImmunoglobulin Heavy ChainsImmunoglobulin Variable RegionModels, GeneticPeptide MappingJournal Article

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M Wan, F Y Shiau, W Gordon, G Y Wang. 1999-02-20. Variant antibody identification by peptide mapping.. https://doi.org/10.1002/(sici)1097-0290(19990220)62%3A4%3C485%3A%3Aaid-bit12%3E3.0.co%3B2-e

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