Multiplexed detection of antibodies using programmable bead arrays.

The detection of antibodies in sera has broad applications for detection and monitoring of infectious diseases, autoimmunity, and cancer. Proteomic methods of antigen detection, such as protein microarrays, are excellent clinical discovery tools, but due to both cost and specialization of manufacture, these are limited to screening small numbers of sera. Downstream assays for biomarker validation studies require rapid, reproducible, multiplexed assays for the simultaneous screening of fewer (<100) antigens with hundreds or thousands of sera. Traditional clinical ELISA assays use recombinant proteins, but these are limited by the ability to purify proteins free of cross-reacting contaminants and are limited to one antigen at a time. Here, we describe the application of coupled in vitro protein production with anti-tag capture onto bead arrays, for the rapid multiplexed detection of antibodies in sera. These assays can be readily adapted for detection of any protein-specific infectious, autoimmune, or cancer-specific antibodies.