Schematic of biomaterial-centered, cell-based therapies. A) Scaffolds (macroscale) with porous structure seeded with cells prior to implantation; B) Hydrogels (macroscale) with crosslinked structure (chemical, ionic, physical) that gels in vitro or in situ containing encapsulated cells ; C) Microcapsules consisting of hydrogel-core/shells, liquid-core/shells, cell-core/shells that contain cells surrounded by a semi-permeable membrane that can be injected into specific tissue sites; D) Microcarriers (similar to scaffolds) with a porous structure seeded will cells prior to injection.