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Semin Reprod Med 2006; 24(5): 304-313
DOI: 10.1055/s-2006-952152
Copyright © 2006 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA.

Embryonic Germ Cells: When Germ Cells Become Stem Cells

Candace L. Kerr1 , John D. Gearhart1 , Aaron M. Elliott2 , Peter J. Donovan3
  • 1Institute for Cell Engineering, Department of Obstetrics and Gynecology, Johns Hopkins University, Baltimore, Maryland
  • 2Department of Microbiology and Immunology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania
  • 3Stem Cell Research Department of Developmental and Cell Biology/Biological Chemistry, University of California Irvine, Irvine, California
Further Information

Publication History

Publication Date:
22 November 2006 (online)

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ABSTRACT

Embryonic germ cells (EGCs) are pluripotent stem cells derived from primordial germ cells (PGCs). PGCs are progenitors of adult gametes, which diverge from the somatic lineage between late embryonic to early fetal development. First derived in the mouse, EGCs have also been derived from human, chicken, and pig. As pluripotent stem cells, EGCs demonstrate long-term self-renewal via clonal expansion in an undifferentiated state, and differentiate in vitro to form embryoid bodies containing cells that represent all three germ layers as well as mixed cell populations of less differentiated progenitors and precursors. This is also demonstrated in vivo by their formation into experimentally induced teratocarcinomas following transplantation. Furthermore, mice, pig, and chicken EGCs have also been shown to contribute to experimentally produced chimeric animals, including germline transmission. Importantly, EGCs demonstrate normal and stable karyotypes as well as normal patterns of genomic imprinting, including X-inactivation. Transplantation studies have begun in a variety of models in hopes of defining their potential use to treat a wide variety of human conditions, including diabetes and urological and neurological disorders.

KEYWORDS

Embryonic germ cells - primordial germ cells - pluripotency - stem cells

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Peter J 

Donovan, Department of Developmental and Cell Biology/Biological Chemistry, University of California Irvine

2054 Hewitt Hall, Irvine, CA 92687

Email: pdonovan@uci.edu

John D Gearhart

Institute for Cell Engineering, Department of Obstetrics and Gynecology, Johns Hopkins University

733 N. Broadway, Broadway Research Building Suite 771, Baltimore, MD 21205

Email: jgearhart@jhmi.edu