Fig. 8

Comparison of microfluidic cultivation of human bone-cell-derived spheroids during a total of 4 days of cultivation. Spheroids cultivated in the open microwells (A) exhibited significantly higher size compared to closed platforms (B, C, D). L Graphical analysis of spheroid mass. The closed microwells (B) produced significantly higher spheroids than static closed microwell-pillar platforms (C). There was no significant difference between the dynamic microwell-pillar platform (D) and the closed microwells (B). E-H Propidium iodide staining showed the positive effect of dynamic cultivation on spheroids viability (M). I, J, K Photos of the used platforms. J Relative mRNA expression levels of osteogenic markers of pooled spheroids using the 3D cell culture platform after 3 days of cultivation under dynamic conditions in comparison to static on-chip cultivation regimes. L n = 120, **** p < 0.0001. M n = 70, **** p < 0.0001. J Data are expressed as mean ± SD relative to beta-actin housekeeping gene for n ≥ 2 (Two-way ANOVA with Tukey’s post-hoc test *** p = 0.0002, **** p < 0.0001). Platforms for spheroid mass measurement were captured under 100x magnification. PI staining was analysed for 60x and 100x magnification objectives