Application of Adipose-Derived Stem Cells in Treatment of Bone Tissue Defects

Despite excellent self-regeneration capacity of bone tissue, there are some large bone defects that cannot be healed spontaneously. Numerous literature data in the field of cell-based bone tissue engineering showed that adipose-derived stem cells (ADSCs) after isolation could be subsequently applied in a one-step approach for treatment of bone defect, without previous in vitro expansion and osteoinduction. However, standard approaches usually involve in vitro expansion and osteoinduction of ADSCs as an additional preparation step before its final application. Bioreactors are also used for the preparation of ADSC-based graft prior application. The commonly used approaches are reviewed, and their outcomes, advantages, disadvantages, as well as their potential for successful application in the treatment of bone defects are discussed. Difficulty in spontaneous healing of bone defects is very often due to poor vascularization. To overcome this problem, numerous methods in bone tissue engineering (BTE) were developed. We focused on freshly isolated stromal vascular fraction (SVF) cells and ADSCs in vitro induced into endothelial cells (ECs) as cells with vasculogenic capacity for the further application in bone defect treatment. We have reviewed orthotopic and ectopic models in BTE that include the application of SVFs or ADSCs in vitro induced into ECs, with special reference to co-cultivation.