Scientific Director, Material Science Bristol-Myers Squibb/Translational Sciences Princeton, New Jersey
Recombinant protein calibrator total protein concentration may not provide an ideal correlation to its LBA-specific activity, thus leading to lot-to-lot variability that directly impacts assay performance. Calibration-free concentration analysis (CFCA) will be introduced and expanded upon to develop a method to quantify the concentration of calibrator which contains functional epitopes that can be recognized by the LBA binding partners. Defining the concentration of a protein calibrator exclusively by the LBA-active molecular species appears to decrease lot-to-lot variability in the ligand binding assay, as compared to conventional total concentration assays. Using Biomarker X as a case study, this novel method led to a decrease in LBA %CV from greater than 40% using total protein concentration to less than 10% using the LBA active concentration. Along with unifying calibrator lots, this method may also prove useful in reagent stability testing, and quantifying the concentrations of each component of a multiplexed calibrator panel.
Learning Objectives:
Define and describe an alternate measure of recombinant protein concentration for use in LBAs.
Additionally, they will understand how this orthogonal measurement can improve assay precision accuracy, and sensitivity.
Describe the SPR techniques for epitope specific concentration analysis