FIGURE 4.

Gene expression of chondrogenic markers expressed by human articular chondrocytes (hAC) (Donor 3) encapsulated in gelatin methacryloyl (gelMA) and cultivated under different conditions for 21 days. Cells encapsulated in P3 or P5 in either soft (7.5%) or stiff (10%) gelMA and cultivated in 0, 1 or 10 ng/mL TGF‐ß3. As a control, hAC were cultured in pellet culture. Differentiation indices calculated from COL2/COL1 and aggrecan (ACAN)/versican (VCAN) are shown. Culture in 10 ng/mL TGF‐ß3 showed upregulation of all genes. Cells cultured within gelMA with 10 ng/mL TGF‐ß3 showed similar differentiation indices when compared to control (pellet culture). Culture within lower concentrations yielded in lower gene expression of gelMA in comparison to pellet culture. In P5 a similar potential to re‐differentiate chondrocytes was found as in P3