Fig. 4

NMB expression during chondrogenesis. A Detection of NMB (13 KDa) and β-actin (45 KDa) proteins in BM-MSCs at d0 and micropellets at d3 by Western blotting (left panel) and their respective quantification (right panel). B Relative expression of NMB and NMBR in BM-MSCs from healthy and OA donors quantified by RT-qPCR. Results are expressed as mean ± sem (n = 3 biological replicates). C Chondrogenic differentiation of BM-MSCs characterized by increased gene expression of SOX9, collagen type IIB (COL2A1varB), aggrecan (ACAN) and collagen type X (COL10A1) at d21 compared to d0 (left panel) (n = 6 biological replicates). Kinetics of NMB expression during chondrogenesis of BM-MSCs isolated from healthy (middle panel) or OA (right panel) donors and cultured with or without TGFβ3 (n = 3 biological replicates by group of donors). D Correlation between NMB expression in BM-MSCs at d0 and chondrogenic markers (SOX9, COL2A1varB, ACAN, COL10A1) at d21 of chondrogenic differentiation (n = 17). *: p ≤ 0.05, **: p ≤ 0.01