Successful Low-Cost Scaffold-Free Cartilage Tissue Engineering Using Human Cartilage Progenitor Cell Spheroids Formed by Micromolded Nonadhesive Hydrogel

Figure 3

The CPC spheroids formed in the micromolded nonadhesive hydrogel with 800 μm diameter in each circular recesses showed a high percentage of viability after spontaneous chondrogenesis. (a, b) Dot-plot graphs showing CPC positive for only CD44 in blue and double positive for CD44 and 7AAD in pink, after digestion of spheroids cultivated for 2 (a) and 21 (b) days. The viable cells were identified by 7AAD exclusion, outside the region R1. (c) The graph represents the percentage of viable cells in three different samples (). (d, e) Dot-plot graphs of annexin V and PI evaluation showing CPC positive for annexin V in Q2 and Q4, after digestion of spheroids cultivated for 2 (d) and 21 (e) days. (f) The graph represents the percentage of apoptotic cells (annexin V positive cells) in three different samples (). 7AAD: 7-actinomycin D; CD: cell cluster of differentiation; PI: propidium iodide.

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