Fig. 3.

Biological functional evaluation of cell-laden VDGH microgels in vitro. A) Cell seeding efficiencies on VDGH microgels of different particle sizes. B) The cell loading efficiency decreased significantly when the cell concentration increased to 80 mil/mL. C) The cell number (per microgel) proliferated on VDGH microgels of different particle sizes on days 1, 7, and 14. D) Live/Dead staining showed the live cells (green) increase over time with few dead cells (red). F-actin (green) and DAPI (blue) staining showed the cellular morphology and a gradual increasing trend during in vitro culture at days 1, 4, 7, and 14. E) Cell viability on different microgels (GH, DGH, and VDGH) during in vitro culture at days 1, 4, 7, and 14. F) SEM images show that the cells and extracellular matrix on the surface of the VDGH microgels increased after 14 days of in vitro culture. GH: GelMA/HAMA microgels; DGH: DBM-loaded GelMA/HAMA. Statistical significance: **p < 0.01. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)