title: Development and validation of an alpha fetoprotein immunoassay using Gyros technology.
abstract: Circulating alpha fetoprotein (AFP) is a diagnostic and prognostic biomarker for hepatocellular carcinoma (HCC) with potential utility as a pharmacodynamic endpoint in rodent tumor models. This application is limited, however, by low sample volumes, highlighting the need for sensitive, sample-sparing biomarker assay methods. In order to improve the utility of AFP as an oncology biomarker, we developed a method for AFP using the Gyrolab™, an automated microimmunoassay platform. Commercially available antibodies were screened to identify optimal combinations that were then used in a multi-factorial design of experiments (DOE) to optimize reaction conditions. Analytical validation included assessments of accuracy and precision (A&P), and dilutional linearity/hook effect, as well as reagent and sample stability. The method is reliable, with total error, a measure of accuracy and precision, less than 30% for all concentrations tested. AFP concentrations were measurable in diseased mice and undetectable in normal mice. Therefore, this novel, low volume AFP immunoassay is suitable for pre-clinical drug development, where its miniaturized format facilitates serial sampling in rodent models of cancer.
authors.affiliation: Pfizer Worldwide Research & Development, Pharmacodynamics, Metabolics and Dynamics, La Jolla, CA 92121, United States.
authors.forename: Allison M
authors.initials: AM
authors.lastname: Given
authors.forename: Pamela M
authors.initials: PM
authors.lastname: Whalen
authors.forename: Peter J
authors.initials: PJ
authors.lastname: O'Brien
authors.forename: Chad A
authors.initials: CA
authors.lastname: Ray
mesh_terms: D000818:Animals; D000906:Antibodies / Q000737:chemistry; D057205:Automation, Laboratory / Q000379:methods*; D001774:Blood Chemical Analysis / Q000379:methods; D007118:Immunoassay / Q000379:methods*; D051379:Mice; D008813:Mice, Inbred ICR; D016513:Mice, SCID; D015203:Reproducibility of Results; D000509:alpha-Fetoproteins / Q000032:analysis*
chemical_list: D000906:Antibodies; D000509:alpha-Fetoproteins