A2_8 Detection of Antibodies

Conventional immunoassays utilize antibodies to “fish” for complementary antigens: the target analytes. The same principles apply when antibodies are the targets, and antigens are used as the “bait”, but in practice antibody assays have unique challenges. In a conventional immunoassay the developer can select the antibodies to engineer the desired assay performance characteristics. But in an antibody assay, the antibody populations may be highly variable between samples.

This chapter examines immunoassay tests for antibodies relevant to infectious diseases. Assay formats and selection of capture and detection reagents, are reviewed, and the use of blocking reagents is explained. The unique issues concerned with estimating antibodies in samples are described. Key performance targets are highlighted for antibody tests. There follows a review of the different applications of antibody tests, including blood bank testing, confirmation of acute disease status, pathogens that can affect pregnancy, vaccination efficacy, transplantation and immunosuppression monitoring, epidemiology, animal testing and biowarfare. An example algorithm for HIV testing and a profile of different antibody isotypes with time for Epstein-Barr virus infection are presented.

Steven Binder is the Senior Director of Technical Development for the Clinical Diagnostic Group at Bio-Rad Laboratories. He joined Bio-Rad in 1983, where he initially developed and introduced clinical chromatography methods used for catecholamine measurement and hemoglobinopathy screening. He served Bio-Rad as R&D manager for clinical chromatography from 1988 to 1998 and was closely involved in the development of new methods for diabetes monitoring and clinical toxicology. From 1998-2005, he led the development of a fully automated platform for multiplex immunoassay, with an emphasis on autoimmune and infectious diseases. His current work involves the evaluation of novel multiplex and digital technologies, as well as validation and commercial development of new biomarkers.
Steve received a B.A. in History and Science, magna cum laude, from Harvard University. He has authored over 25 papers in peer-reviewed journals and has received 11 US patents.

Jennifer Isler is currently Director of Competitive Intelligence at Pfizer. She was previously a Senior Principal Scientist in Biotherapeutic Bioanalysis at Boehringer Ingelheim in Ridgefield, CT where she managed a group responsible for immunoassay development, validation and implementation for non-clinical and clinical biologic drug development. She is also the Associate Editor for the Journal of Immunoassay and Immunochemistry. After obtaining her Ph.D. in cellular and molecular biology from the University of Pennsylvania, Jennifer did post-doctoral work investigating cellular stress responses to microbial infection. Prior to the Senior Principal Scientist position, Jennifer held positions of increasing responsibility at both Wyeth and Boehringer Ingelheim in the areas of biomarkers and pharmacogenetics.

Antibodies, infectious diseases, Epstein-Barr virus, ELISA, specificity, capture, detection, second antibody, chromogenic, chemiluminescence, fluorescence, blockers, antibody heterogeneity, isotype, relative error, precision, specificity, selectivity, stability, linearity of dilution, limit of dilution, blood bank testing, disease status, pregnancy infections, vaccination efficacy, transplantation monitoring, immunosuppression monitoring, HIV, HIV testing algorithm, epidemiology, animal testing, biowarfare.