Chapter 21 - Derivation of Embryonic Stem Cells from Human Blastocysts

Abstract

Human embryonic stem cells (hESCs) are pluripotent cells derived from the inner cell mass (ICM) of blastocyst-stage embryos. The ICM is a mass of about 50 cells which gives rise to both embryonic and extraembryonic tissues. More than 200 hESC lines have been reported worldwide, and while the earliest hESC lines were derived in medium containing fetal bovine serum (FBS) and/or on mouse feeder layers, more defined conditions are in development. These include derivation on human rather than animal feeder layers, and use of cocktails of purified growth factors instead of serum. There is still a great deal of room for improvement in derivation methods and recently there have been some important advances. In 2006, hESC lines were derived under GMP (Good Manufacturing Practice) conditions specifically for use in cell therapy. Also in 2006, hESC lines were derived under completely defined conditions without feeder layers, and new methods were reported for derivation of hESC lines from single isolated blastomeres. This chapter summarizes the published reports on embryo-derived cell lines and conditions of their culture and method by which several hESC lines from human blastocysts are derived.