Fig. 3

Effect of BMP pathway inhibition or PTHrP pulse treatment on cartilage matrix deposition and expression of differentiation markers

MSCs were subjected to chondrogenic induction for 28 days in the presence of CompA, LDN21 or received PTHrP pulse treatment. Paraffin sections were stained with (A) toluidine blue and (B) safranin O/fast green to visualize proteoglycan deposition or for (C) type II collagen by immunohistochemistry. Shown is one representative experiment of n = 6 MSC donors. Scale bars represent 500 μm for toluidine blue overviews and 200 μm for magnified pictures. (D) Quantification of GAG and DNA content (n = 5 MSC donors). (E) Expression levels of indicated genes with HNRPH1 and CPSF6 as reference (n = 6 donors). In D-E, respective control cultures were set to 1 (dashed lines). Boxes represent the interquartile range (IQR, 25th to 75th percentiles), lines inside the boxes represent the median, whiskers extend to minimum and maximum values. Outliers are depicted as ○ and extreme values as ◊. * p ≤ 0.05 Mann-Whitney U test compared to respective controls