EpCAM-Independent Enrichment and Detection of Viable Circulating Tumor Cells Using the EPISPOT Assay.

ABSTRACT

Identification and characterization of circulating tumor cells (CTCs) in peripheral blood can provide information on the direction and the efficacy of treatments. Current techniques such as CellSearch® are limited in differentiating between apoptotic and viable CTCs. In contrast, the fluorescent EPISPOT assay allows for the identification of viable cells by detecting proteins secreted/released/shed by functional single epithelial cancer cells. In addition, as CTCs are rare events, it is required to combine the EPISPOT assay with an enrichment step. In this article, the EPISPOT assay, as well as two technologies for enrichment of viable CTCs, RosetteSep™ and Parsortix™ techniques, will be presented and discussed in detail.