Variation in Osteogenic Differentiation Capacities of Adipose-derived Stromal Cells by Anatomic Depot

Although bone marrow has long been studied as the primary source of mesenchymal stem cells (MSC), adipose tissue has been increasingly studied as a rich source of tissue resident MSC. Since the first description of adipose-derived MSC, or adipose-derived stromal cells (ASC), it has been clear that ASC have significant advantages for clinical translation, including increased cell frequency, high growth potential, and residence in a dispensable and accessible location (subcutaneous fat). Nevertheless, it is increasingly clear that ASC differ by anatomic location, although the exact differences between anatomic depot are not entirely agreed upon. Striking differences exist between subcutaneous and visceral fat depots, but even more interesting between various anatomic regions within subcutaneous fat. Understanding the specific manners in which ASC differ by location is especially important in the context of tissue engineering. In summary, the current literature regarding ASC clearly shows that not all fat is created equally. Clear cut, and for the most part reproducible, differences exist in the osteogenic potential, adipogenic potential and proliferation of ASC depending on their site of origin. How this information should be used is still a matter of uncertainty.