Système microfluidique pour le tri et l'analyse de cellules dans le diagnostic du cancer

This project is aimed at developing a new integrated microfluidic system for high throughput cell sorting and analysis. This micro-device will be able to sort rare population of cells, like circulating tumor cells (CTC) in whole blood, and analyze them by bright field and fluorescence microscopy at high magnification. Evaluating the concentration of CTC in blood will have a strong diagnosis and prognosis value, for evaluating risks of metastases and tumor cells dissemination. Cell sample flows through an array of magnetic columns that are coated with antibodies. These antibodies are specific of membrane protein that are expressed by the target cells and allow their capture in chip. Once they are trapped on columns, their shape and the expression of other proteins are observed by microscopy. As a proof of concept, Raji cells (B lymphocytes, CD19+) mixed with Jurkat cells (T lymphocytes, CD19-) with an initial concentration of 1/1000 are sorted in an array of magnetic beads functionalized with anti-CD19 antibodies. 500μL of sample are analyzed within 1 hour with a global capture yield of 55 +/- 10 %. The captured cells are then stained with immunofluorescent probes which provide membrane (anti- CD19-AlexaFluor 488) and nucleus (Hoechst) imaging. Imagining can be performed at high resolution microscopy, including 100X oil immersion objectives.