Whole slide imaging of circulating tumor cells captured on a capillary microchannel device

Abstract

Liquid biopsy with circulating tumor cells (CTCs) can aid in cancer detection at early stages and determine whether a certain treatment is effective or not. However, existing CTC techniques focus on one or two aspects of CTC management including sampling, enrichment, enumeration, and treatment selection. This paper reports an integrated capillary microchannel device that allows efficient capturing of CTCs with a wide microchannel, rapid enumeration of captured CTCs with whole slide cell imaging, and in situ drug testing with captured CTCs. Blood is drawn into the microchannel whose height is appropriate to the diameter of cancer cells, while its width is a thousand times larger than the diameter of cancer cells. The inner bottom surface of the microchannel is modified with long chain polymers that have cell adhesive ends to efficiently capture CTCs from blood. With this design, cells including CTCs are forced to move through the polymer coated microchannel, and the chance of cell adhesive ends interacting with specific antigens overexpressed on surfaces of cancer cells is significantly enhanced without a channel blockage issue. Captured CTCs are enumerated with a whole slide imaging platform via dual LED autofocusing technology then exposed to anti-cancer drugs, followed by live/dead assay and fluorescence imaging. Given its straightforward, easy and powerless operation, this device with whole slide imaging will be useful for cancer diagnosis, prognosis and point-of-care treatments.