Fig. 3

Removal of the blood vessel reduced the initiation time of MSC-EMs. The time between consecutive MSC-EMs (induction time) was observed for approximately 2 months for the different preparation methods. A culture was rated as induced when the cell number reached approximately 10⁵ cells in a well. Depicted are the means and the standard deviations. As the first initiation of an MSC-EM usually takes longer than all consecutive MSC-EMs, we excluded the first time point from the statistical analysis. A Kruskal-Wallis test revealed significant differences among the preparation methods (p = 3.2e−07). A subsequent pairwise Wilcoxon-Rank-Sum test with Bonferroni-Holm correction showed significant differences for BLRV vs BLOP (p = 1.4e−05), BLRV vs Std (p = 8.5e−05), and no significant differences between Std vs BLOP (p = 0.88). n = 5–22 (at least 4 donors for each preparation method). Std = standard preparation, BLOP = blood vessel cut open, BLRV = blood vessel completely removed