Fig. 23.

Concept of the use of decellularized tissue (organ) as a tissue engineering biomaterial (schematic is not to scale). Decellularized tissue (organ) can be obtained by the decellularization of living tissue (organ). The resulting cell-free ECM can be modified (e.g., by heparin crosslinking and growth factor binding) before implantation. To this end, the ECM scaffold can be reseeded with ex vivo-cultured cells that “prime” the biomaterial (e.g., to enhance its ability in vascularization or remodeling) and/or “get primed” toward a specific cell fate decision (e.g., to proliferate or differentiate). Such a cell–matrix construct could induce tissue regeneration by the combined action of seeded and recruited cells in a functionalized native matrix. Alternatively, modified ECM can be directly transplanted into a patient without cell seeding. In this case, tissue regeneration entirely relies on the capacity of the ECM material to instruct resident cells toward target recruitment, specific differentiation and subsequent tissue formation (endogenous tissue regeneration).