Chondrogenic differentiation of human adipose derived stem cells: The roles of mechanical loading, elevated calcium, and the extracellular calcium sensing receptor.

摘要

Cartilage defects caused by injury or disease affect millions each year. Human adipose derived stem cells, hASC, have emerged as an opportune cell source for cartilage tissue engineering. This research first aims to observe the optimal conditions to direct chondrogenic differentiation, focusing on the role of mechanical loading, through a review of the literature. Because of Ca2+ affects in both chemical and mechanical signaling, hASC were pellet cultured in chondrogenic differentiation media with elevated Ca2+. These pellets demonstrated diminished chondrogenesis, and a layer of calcified, hypertrophic cartilage. To better understand the mechanism by which Ca2+ hASC were cultured with either transient knockdown of Polycystin, PC2, or allosteric binding of the extracellular calcium sensing receptor (CaR) in elevated Ca2+. Modulating the CaR affects the impact of elevated Ca2+ in hASC differentiation. The use of Ca2+ and its various mechanisms for cell signaling will prove to be a valuable tool in developing novel techniques for tissue engineering.