Identifying Qualitative and Quantitative Differences in Recombinants and Antibody Enrichments for IGF1 as Provided by Different Vendors and Different Preparations Using High-Resolution Mass Spectrometry
on 08-01-201308:36 AM - edited on 10-15-202111:38 AM by AnalyteGuru
Prakash A, Krastins B, Peterman S, Sarracino D, Garces A, Athanas M, Sutton J, Oran P, Nelson R, Lopez M. HUPO 2012 Poster Purpose: To understand the differences in purity, sequence, length, structure and post-translational modifications (PTMs) of various recombinant forms of insulin-like growth factor 1 (IGF1) and the differences in specificity of antibodies against IGF1.
Methods: Recombinant IGF1 samples from 6 vendors were analyzed. In addition, 6 different antibodies were used to enrich for the recombinant protein spiked in human serum in the endogenous forms. In total, this created 12 different samples containing the protein. These were analyzed by liquid chromatography and high-resolution mass spectrometry.
Results: While all recombinants and antibodies performed as commercially described, we identified subtle differences in their sequences and structures. Similarly, the various antibodies have different epitopes that they bind to and as a result have varying specificity.