Detection of Circulating Tumor Cells using the SPECTRA Light Engine®
Application SpotLIGHT August 2021
Detection of circulating tumor cells (CTC) is in widespread development as a noninvasive “liquid biopsy” for early-stage cancer diagnosis. CTCs are cells that circulate in the blood and the lymphatic system after becoming detached from a primary tumor (Figure 1). The main challenge in detection of CTCs is their extremely low abundance. The critical level for diagnosis is about 1 CTC per milliliter of blood against a background of millions of white cells and billions of red cells. Detection of CTCs is accomplished by cellular enrichment, using one of several strategies  followed by immunofl uorescence discrimination of CTCs from normal blood cells. Lumencor light engines provide illumination for immunofl uorescence imaging in many commercial CTC detection systems currently undergoing development and validation. One such system, recently described by Jou and co-workers , uses a microfl uidic device with embedded streptavidin-coated nanopillar arrays to capture target cells preincubated with biotinylated anti-EpCAM and anti-N-cadherin
antibodies. Using illumination from a SPECTRA Light Engine, CTCs are identifi ed as FITC–EpCAM positive/TRITC–CD45 negative/DAPI positive. Increased specifi city can be achieved by expanding the multiplex immunostaining panel with the cancer stem cell specifi c marker CD13 (Figure 2). The entire process of CTC enrichment, immunostaining, slide scanning, image analysis and cell classification is automated, resulting in improved reproducibility and increased throughput compared to protocols involving manual processing.
- Aug 09, 2021