(160d) Three-Dimensional Culture of Human Adipose-Derived Stem Cells By Surface Modification Using Elastin-Based Copolymers

During their differentiation and maturation into adipocytes in vitro, human adipose derived stem cells (hASCs) begin to accumulate lipids during maturation and begin to become more buoyant over time. Such fat-laden cells eventually lift off of the culture surface and are lost during the next media change. Because of the loss of physiologically relevant spheroids, elastin-like polypeptide-polyelectrolyte coated surfaces were used to form spheroids for long term culture, in order to provide a proven, long term culture method for mature adipocytes in vitro. While there are several methods of forming spheroids, there is not a general consensus on which methods are the most useful for stem cell proliferation, differentiation, and maturation ability. This is also true for most cell types, including adipocytes. Overall, our research provides a proven cell culture model for future studies involving long-term culture of mature adipocytes derived from hASCs. In addition to using elastin-like polypeptide-polyelectrolyte coated surfaces, alternative methods such as hanging drop, ultra-low attachment plate culture, and suspension cultures were compared for their ability to form and retain productive hASC spheroids. It was found that there are differences in spheroid formation and maturation within different molecular weights of the same polyelectrolyte, polyethyleneimine, as well as different compositions of the same molecular weight. Though the selected alternative spheroid forming methods were comparable to the elastin-like polypeptide-polyelectrolyte coated surfaces in terms of adipogenic maturation, the coated surfaces had greater amounts of spheroid retention, which allows for more physiologically relevant spheroids to be acquired.