Primate embryonic stem cells

Primate embryonic stem (ES) cells are derived from preimplantation embryos, have a normal karyotype, and are capable of indefinite, undifferentiated proliferation. Even after culture for more than a year, primate ES cells maintain the potential to differentiate to trophoblast and derivatives of embryonic endoderm, mesoderm, and ectoderm. In this review, we compare the characteristics of ES cell lines from two primate species, the rhesus monkey (Macaca mulatta) and the common marmoset (Callithrix jacchus), with the characteristics of mouse ES cells and human embryonal carcinoma cells. We also discuss the implications of using primate ES cells to understand early human development and discuss the practical and ethical implications for the understanding and treatment of human disease.