Potential Synergistic Effects of Stem Cells and Extracellular Matrix Scaffolds

In recent years, extracellular matrix (ECM)-derived biomaterials have been used as scaffolds to help regenerate diseased or damaged tissues. These biomaterials are prepared by decellularization of a tissue of interest by chemical or physical removal of the cellular components. The goal of the decellularization process is to remove cells without disturbing tissue-specific composition, growth factor content, and, in some cases, the mechanical properties. As decellularization can be achieved without significantly affecting the native architecture of the tissue or organ of interest, it provides a scaffold material with native-like composition and structure. ECM scaffolds promote constructive remodeling through several mechanisms that include chemotactic properties, growth factor release, and modulation of the immune response. Constructive remodeling by ECM scaffolds relies, in part, on the recruitment of neighboring or circulating cells to the wound site. However, this is a relatively lengthy process, and the cells recruited may not be sufficient for complete tissue repair, suggesting that there might be applications that would benefit from the combination of a cellular component with an ECM biomaterial. Stem cells represent a potential therapeutic cell source with clinical evidence of potential beneficial effects. This review will describe how ECM scaffolds can help localize stem cells to the site of injury while directing stem cell differentiation and modulating the response toward tissue regeneration. As the field of tissue engineering takes its next steps, recellularized ECM scaffolds could become the next dass of promising bioengineered constructs. This review covers the advantages of acellular ECM scaffolds and the potential beneficial effect that seeding stem cells in the scaffold has on tissue regeneration.