Fig. 3

Chondrogenic differentiation of BS cells and BMSCs. Cells cultivated in chondrogenic medium showed strong staining for proteoglycans determined by positive alcian blue staining (Alc Blue) and were also positive for collagen type II (COL II) in BS cells as well as in BMSC compared to cells cultivated in control medium (a). Left scale bar = 200 μm; right scale bar = 100 μm. b Expression of chondrogenic marker genes was evaluated using RT-PCR. Cultivation in the presence of chondrogenic medium (Ch) resulted in an increased expression of aggrecan (AGN), decorin (DEC), SRY (sex determining region Y)-box 9 (SOX9), indian hedgehog (IHH), and collagen type II (COL II) as compared to untreated cells (Co) for both cell types. Expression levels of the housekeeping gene elongation factor 1α (EF1α) are shown in the last row. Representative images from three different donors are shown. BMSCs bone-marrow derived mesenchymal stem cells BS bursa subacromialiss