Characterization of Human Embryonic Stem Cells

Human embryonic stem cells (hESCs) hold great therapeutic promise since they are capable of generating specialized cells that may be utilized to replace damaged tissues in patients suffering from various types of diseases. However, this application is dependent on a comprehensive understanding of the signalling mechanisms involved in ESC lineage restriction, an area in which further scientific proficiency is needed. Moreover, the development of clinical applications using hESCs rests on the formulation of appropriate culture conditions that would allow for the isolation and maintenance of homogeneous, genetically and epigenetically stable cell populations. The stability of these cells is critical to diminish potentially adverse effects following transplantation, such as host rejection, low survival of the grafted cells and maybe even tumor formation. In this chapter I will describe the current techniques for isolating, characterizing and maintaining hESCs in culture. I will address some of the challenges underlying these methods and, when possible, offer alternatives that may help overcome these challenges. Finally, I will discuss the current limitations that have made hESC-based therapy a discipline still in its infancy and we will provide my view of where the field of personalized stem cellbased medicine is likely to go in the future.

Keywords: hESC derivation, hESC characterization, stem cell niche, pluripotency.