Figure 7
Differential gene expression modulation under hypoxia during a kinetic chondrogenic differentiation of UCM-MSCs and UCB-MSCs. UCM-MSCs and UCB-MSCs were cultured in type I/III collagen scaffolds at 21% or 3–5% O2 during 7, 14, 21 and 28 days in ICM supplemented with BMP-2 (50 ng/ml) and TGF-ß1 (10 ng/ml). Relative mRNA expression was determined by RTqPCR. All results for each MSCs source were normalized versus untreated MSCs incubated during 1 h in type I/III collagen scaffolds at 37 °C and presented as the relative expression of each gene. (A) Effect of hypoxia on chondrogenic differentiation after 28 days of culture in the presence of growth factors. (B) Summary of the relative effects of hypoxia on different genes expression: differential time-dependent profile between MSCs sources and upon growth factors treatment. Manual classification of mRNA expression variation by hypoxia was realized by taking into account only the significant results between hypoxia versus normoxia at the same time of measurement or between hypoxia versus normoxia at 7 days. (C) Col2a1/Col1a1 ratio (Q-Ratio) was presented for UCB-MSCs cultured in ICM. Box-plots represent five independent experiments for each MSCs source. Statistically significant differences between normoxia and hypoxia conditions were determined using the Mann Whitney test. *: Hypoxia versus normoxia at the same time (*p < 0.05, **p < 0.01).
