A method of collecting and delivering single or precise numbers of cells to assess the feasibility of capturing very rare circulating tumor cells for human breast cancer diagnosis and monitoring was developed. A PMMA device was assembled with minimal assembly variation using passive alignment. Thermoplastic fusion bonding was optimized to yield minimal deformation of the microfluidic channel. UV modification and an anti-epithelial cell adhesion molecule (anti-EpCAM) functionalization process were used to generate capture surfaces and maximized by control experiment. Single or precise numbers of target cells were collected using a cell collecting capillary tube and a hemacytometer and delivered into the microchannel without any loss. Cells from one of the human breast cancer cell lines, the MCF-7 cell line (ATCC, Manassas, VA) which strongly overexpresses EpCAM, were successfully captured on the anti-EpCAM coated microchannel surfaces. Successful capture of early stage breast cancer cells in whole blood may be feasible with further optimization of the microchannel geometry and flow velocity through the microfluidic device.
Detection and quantification of circulating tumor cells in mouse models of human breast cancer using immunomagnetic enrichment and multiparameter flow cytometry
