Fig. 4

For BM-MSC-conditioned medium, the images in a time series (T0, T15, T18, T20, T22, T24) were analyzed for gap area over time (a–f). For AT-MSC-conditioned medium, the images in the same time series were analyzed (g–l). Photomicrographs from the control group in a defined time series (m–r). Graphical comparison of the mean ingrowth and standard deviation (SD) of control, BM-MSC, and AT-MSC groups. P values ≤ 0.05 were considered statistically significant (s); ×10 magnification, scale bar 200 μm