Analyses for cell viability and apoptosis within mesenchymal stem cell pellets after chondrogenic induction. Following genetic modification with (b) Ad.IHH (IHH), (c) Ad.IHH + Ad.TGF-β1 (IHH + TGF-β1), (d) Ad.IHH + Ad.BMP-2 (IHH + BMP-2) and (a) Ad.GFP (negative control) at 5 × 102 virus particles/cells, cultures were double-stained with 6-carboxyfluorescein diacetate (CFDA) (left panels) and Annexin 5 (right panels) at days 10 and 21 of culture. Representative fluorescence microscopy images are shown. Note that living cells are stained green with CFDA, late apoptotic cells red with Annexin 5-Cy3, while early apoptotic cells stained for both CFDA and Annexin 5. Panels are reproduced at low (50× bar = 200 μm) or high (200×; bar = 50 μm) magnification as indicated. Ad., adenoviral vector; BMP, bone morphogenetic protein; IHH, Indian hedgehog; TGF-β, transforming growth factor beta.
Steinert et al. Arthritis Research & Therapy 2012 14:R168 doi:10.1186/ar3921