A popular type of stem cell in the research and clinical communities is what is known as the adipose tissue-derived mesenchymal stem cell, which are stem cells that come from fat tissue. A review published last year in Stem Cells International has provided a comprehensive picture of what makes these stem cells beneficial for treating disease and injury.
One characteristic of adipose tissue-derived mesenchymal stem cells that originally made them popular is the ease with which they are accessed. Gaining access to fat tissue is relatively simple compared to accessing other types, such as those from the bone marrow. Other attractive features have been their abundance and the ability to use them with no ethical concerns.
While all adipose tissue-derived mesenchymal stem cells have these advantageous features, there are a number of types of adipose tissue-derived mesenchymal stem cells, and researchers are still working to determine the relative advantages of each of these types. For instance, there are types that come from white adipose tissue and types that come from brown adipose tissue. Much brown adipose tissue exists in fetuses and newborns and transforms to white adipose tissue with aging. Understanding how these different types of adipose tissue work therapeutically will be important for determining when and how to use these cell types. Overall, though, it seems that adipose tissue-derived mesenchymal stem cells from younger patients proliferate at higher rates than those from older patients.
Adipose tissue-derived mesenchymal stem cells also differ in their properties depending on how they were harvested and the environment in which they are put. The two procedures for harvesting these cells are called resection and lipoaspiration. One study found that when cells were extracted with lipoaspiration, a higher abundance of cells could be obtained, whereas the proliferation of the cells was similar with both harvesting procedures. Environmental factors, including which trophic factors are present, the hydrostatic pressure, and the fluid sheer stress, also impact the ability of the cells to proliferate and differentiate. Other factors, such as the specific growth factors produced and the surface markers that are present, also impact the utility of adipose tissue-derived mesenchymal stem cells.