Figure 3.

Hematoxylin and eosin staining of in vitro engineered cartilage. The sample in the HP group shows relatively homogeneous cartilaginous features with abundant lacuna structures, strong extracellular matrix staining, and the thickest cartilage formation. Samples in the shear and centri groups also form cartilaginous tissue with a certain thickness, but obvious heterogeneous structures are observed in the central regions. Cartilage formation in the static group is observed only in the outer region of the sample. Red frames indicate the outer cartilaginous regions and yellow frames indicate the central regions. Red arrows indicate polyglycolic acid residuals. Abbreviations: centri, centrifugal force control group; HP, hydrostatic pressure.