Recent Advances and Challenges in Adipose Tissue Engineering: Adipose Derived Stem Cell-based Approaches

Adipose tissue is now well recognized as a ubiquitously available and reliable source of multipotent adult stem cells. In the context of increasing clinical demand for adequate implants to repair soft tissue defects resulting from postoperative, congenital or posttraumatic loss of the subcutaneous fat layer, adipose tissue engineering (ATE) represents an exciting therapeutic strategy in plastic and reconstructive surgery. The ATE approach includes two different strategies: in situ adipogenesis for small volume loss, and in vitro development of three-dimensional (3D) tissue-engineered constructs (TECs) for large adipose tissue defects. These strategies can involve the use of living cells and/or biocompatible scaffolds and/or biomolecules. The focus of this review is on the use of adipose-derived stem cells (ASCs) as the cellular component of TECs for regenerative purposes. These cells have emerged as a promising type of stem cells with clear advantages over previously used mesenchymal stem cells, such as those derived from bone marrow (BM-MSCs) because of the easy and repeatable access to subcutaneous tissue, the simple isolation procedures, increased proliferation in culture and the potential to differentiate into cells of mesodermal origin as well as cells of non-mesodermal lineage. The culture strategies, immunophenotype, proliferation and differentiation potentials of ASCs, together with current clinical data with respect to their use in soft tissue regeneration and augmentation will be summarized. The article will also review the key advances in the development of biomaterial scaffolds and biomolecules aiming to control the cell response, as well as the possible challenges in this scientific field.