Fig. 1.

Three-dimensional bioprinting as a tool to produce microscopic anisotropic scaffolds. Biomaterial and bioink were prepared by mixing neutralized Col 1 (5 mg/ml) isolated from rat tails using THA (25 mg/ml). Neutralized Col 1 was mixed with THA for enzymatic cross-linking with either cell-free or hMSC-containing micropellets. The Col 1 microstructure was investigated after 3D printing and compared with casted, isotropic samples with different microscopic techniques (second-harmonic generation [SHG] imaging and confocal microscopy). Cell-instructive properties were analyzed after in vitro culture on cell migration and attachment. THA = tyramine derivative of hyaluronan; Col 1 = collagen type I hydrogel; hMSC = human bone marrow–derived mesenchymal stromal cell; HRP = horseradish peroxidase; SHG = second-harmonic generation.