In vivo assessment of cell-laden scaffolds. In (A), a PEG-RGD hydrogel with no cells (labeled as PEG) or with embedded MSCs at varying stages of osteogenic differentiation (i.e., MSCs or differentiated for 4, 10, or 21 days prior to encapsulation and implantation). Top row shows the host response after 28 days by Masson’s Trichrome and plots indicate quantitative assessment of the thickness of inflammatory cells at the surface of the hydrogel implant and the thickness of the resulting fibrous capsule. Reproduced with permission from [35]. In (B), a polysaccharide coating was applied to a MSC-laden gelatin crosslinked hydrogel. Far left image of scaffold (green) with coating (blue). Histological assessment of the fibrous capsule by Masson’ts trichrome staining and corresponding fibrous capsule thickness quantified. Reproduced with permission from [52].