Monitoring Breast Cancer Cell Apoptosis

An inverted Leica DMi8 equipped with a Retiga R6 camera and Lumencor SOLA SE 365 light engine, using a 5X objective, has been used to acquire Time-lapse images. The filter cubes used were TXRed (excitation filter 560/40 nm, emission filter 630/75 nm, dichroic mirror 585 nm) and GFP (excitation filter 470/40 nm, emission filter 525/50 nm, dichroic mirror 495 nm). A live fluorescent dye (CellTrace, red) was used to selectively pre-stain the cancer cells before cultures on-chip. To monitor apoptotic death, a live fluorescent reporter for caspase activity (CellEvent Caspase-3/7, green) was added to the on-chip culture medium. The red channel was then used to locate cells^{10 (link)} while the transposition on the green channel of the cancer cell position allowed to monitor green emission signal and, therefore, death events. Breast cancer cells (BT474 cell line, representative of HER2 + breast cancer subtype) were co-cultured in 3D biomimetic collagen gels, within microfluidic devices, with immune cells (PBMCs, peripheral blood mononuclear cells from healthy donors), with or without the addition of targeted immunotherapy, the trastuzumab (brand name Herceptin). With the aim to demonstrate the advantage of using DM tool in common practice, we extracted handcrafted features related to green emission and compared the case of standard practice with the use of DM tool.