How specific is CAM for viable tumor cells in blood?
CAM is able to enrich up to 1 million-fold rare cells derived from tissues (tumor, endothelium and bone marrow stem cells) in blood. For detection of CTCs, one can use CAM-enriched cells as primary sorting and identify CTCs by their positivity with epithelial lineage markers such as cytokeratins and epithelial cell adhesion molecules or by their negativity with CD45 (optional, as this has never occurred). For a sample containing 100 CTCs, there are approximately 1,000 CD45+ cells in a CAM-enriched portion that are negative for epithelial markers.
