Fig. 5
From: Multiscale cytometry and regulation of 3D cell cultures on a chip
Co-culture of endothelial cells (BAECs) and 3D hepatoma (H4-II-EC3) in the 3D spheroids a–e and in mixed 3D–2D conditions f–i. a Schematic diagram of the loading protocol for having different conditions on a single droplet array. 7 cell solutions with an increasing ratio of BAECs were successively loaded. b Fluorescent images of one representative spheroid for each BAECs ratio. The BAECs are stained with CellTracker Red and all cells with NucBlue Live reagent. The red and yellow lines represent respectively the edges of the detected spheroids and BAECs cores. On these representative images the contrast is individually set on each frame. Scale bar is 100 μm. c Variation, as a function of the BAECs cell ratio, of c TRITC signal d the number of detected BAECs cores, and e the distance of the core centers to the spheroid center (1 chip, Nspheroids = 355, Ncores = 292). f Schematic diagram of the mixed 3D–2D protocol: the region for 2D culture is coated with fibronectin, the region for spheroid culture is coated with Novec. After differential surface treatment, cells are seeded in the anchors within droplets for spheroid formation, or directly on PDMS treated with fibronectin for 2D culture. g The chip design enables the spatial control over the deposition of different coating solutions, while preventing their mixing. h LIVE/DEAD stained hepatoma spheroids and BAECs monolayer demonstrate controlled spatial distribution. Scale bar is 1 mm. i Higher magnification of the spheroids and BAECs in 2D, stained for LIVE/DEAD. Scale bars are 100 μm. **p < 0.01, ***p < 0.001. Kruskal–Wallis ANOVA followed by Mann–Whitney U-tests with Sidak’s correction for multiple comparisons
