Proximity Extension Assay (PEA) is a 96-plex immunoassay for high throughput detection of protein biomarkers in liquid samples. For each biomarker, a matched pair of antibodies linked to unique oligonucleotides (proximity probes) binds to the respective protein target. As a result, the probes come in close proximity and hybridize to each other. The addition of a DNA polymerase leads to an extension of the hybridizing oligo, bound to one of the probes, creating a DNA amplicon that can subsequently be detected and quantified by quantitative real-time PCR. For detailed information, please read the publication: Assarsson et al (2014) PLOS one.