Fig. 3

Response of CSPCs to NGF. a Change in morphology of CD271⁺ cells upon NGF treatment (10 ng/ml, 24 hours): CD271 (green), nuclei (blue). Bar = 50 μm. b Cells isolated from late OA articular cartilage are chemotactic for NGF (10 ng/ml). p <0.05, *versus control group, #versus NGF + ab group (n = 3, mean ± SD). c Schematic chart of isolation NGF chemotactic cells with Transwell. d Characteristics of NGF chemotactic cells: clonogenicity and differentiation multipotency. bar = 2 cm; osteogenesis, alkaline phosphatase (ALP), bar = 2 mm; adipogenesis, lipid droplet, Oil-red O; bar = 50 μm; chondrogenesis of pellet culture, GAG staining with Safranin O, bar = 500 μm. ab NGF neutralizing antibody, CFU crystal violet, NGF nerve growth factor, OA osteoarthritis