Polymeric microfluidic devices exhibiting sufficient capture of cancer cell line for isolation of circulating tumor cells

Abstract

Here, we developed polymeric microfluidic devices for the isolation of circulating tumor cells. The devices, with more than 30,000 microposts in the channel, were produced successfully by a UV light-curing process lasting 3 min. The device surface was coated with anti-epithelial cell adhesion molecule antibody by just contacting the antibody solution, and a flow system including the device was established to send a cell suspension through it. We carried out flow tests for evaluation of the device's ability to capture tumor cells using an esophageal cancer cell line, KYSE220, dispersed in phosphate-buffered saline or mononuclear cell separation from whole blood. After the suspension flowed through the chip, many cells were seen to be captured on the microposts coated with the antibody, whereas there were few cells in the device without the antibody. Owing to the transparency of the device, we could observe the intact and the stained cells captured on the microposts by transmitted light microscopy and phase contrast microscopy, in addition to fluorescent microscopy, which required fluorescence labeling. Cell capture efficiencies (i.e., recovery rates of the flowing cancer cells by capture with the microfluidic device) were measured. The resulting values were 0.88 and 0.95 for cell suspension in phosphate-buffered saline, and 0.85 for the suspension in the mononuclear cell separation, suggesting the sufficiency of this device for the isolation of circulating tumor cells. Therefore, our device may be useful for research and treatments that rely on investigation of circulating tumor cells in the blood of cancer patients.

Enrichment of circulating tumor cells in tumor-bearing mouse blood by a deterministic lateral displacement microfluidic device

“…To separate CTCs from benign cells in blood, two major approaches can be used: biochemical approaches and biophysical approaches. In biochemical approaches, affinity capture of cell surface antigens (Gao et al 2013;Nagrath et al 2007;Ariyasu et al 2012;Ohnaga et al 2013;Liu et al 2013a;Sheng et al 2013) and fluorescent labeling are generally used to identify CTCs. These examples include the Veridex Cellsearch® system (Raritan, NJ, USA), which has been approved by the U.S. FDA (Food and Drug Administration) for clinical enumeration of CTCs.…”

Capture of mesothelioma cells with ‘universal’ CTC-chip

“…In the previous study, we showed that the 'podoplanin-chip' effectively captured mesothelioma cells of another cell line, ACC-MESO-4 (15), indicating that the novel CTC-chip is a promising modality to detect some kinds of tumor cells including EpCAM-negative cells due to non-epithelial origin (e.g., mesothelioma cells) or undergoing epithelial-mesenchymal transition (EMT). Among a variety of systems for capture EpCAM-negative CTCs such as size-based or density-based separation systems (20), we employed a microfluidic system to capture CTCs called CTC-chip (14,15). The CTC-chip had been originally developed in USA (21), but the original CTC-chip can capture only EpCAM-positive CTCs because an anti-EpCAM antibody to capture CTCs is conjugated and another antibody is not available in the system.…”

“…The cell capture efficiency was represented as N-captured/N-total (14,15). The average and standard error (SE) of capture efficiency were calculated from results obtained in triplicated experiments.…”

“…The CTC-test provided a significant prognostic value in discrimination between MM patients and non-MM patients such as asbestos pleurisy (P=0.036), but the sensitivity was only modest (32.7%) mainly due to negative or low expression of EpCAM on MM cells, which may not be effectively captured with an anti-EpCAM antibody (13). These results clearly indicate the need for a sensitive system for capture EpCAM-negative CTCs, and we have developed a high efficient system to capture CTCs using a microfluidic device 'CTC-chip' (14,15). In the system, CTCs are captured to numerous micro-posts coated with an antibody against an antigen expressed on target tumor cells, and the most important advantage is capability of conjugating any antibody to capture CTCs.…”

Micro- and nanodevices integrated with biomolecular probes

“…8e&f). Antibody functionalized micropillars in microfluidic channels were utilized to increase overall surface area and to enhance target cell–surface interactions, thus improving the capture efficiency of rare CTCs from blood (Hansmann et al, 2011; Nagrath et al, 2007; Ohnaga et al, 2013). Moreover, other studies improved the cell–probe functionalized surface interactions by utilizing microposts from ultra-high porosity CNT forests (Chen et al, 2012).…”