12:00 – 12:30 HRS


Hans Schöler
New Bolton Centre

Co-Authors: 1)Karin Hübner, 2)Guy Fuhrmann, 3)Lane K. Christenson, 1)James Kehler, 1)Rolland Reinbold, 4) Rabindranath De La Fuente, 3)Jennifer Wood, 3)Jerome Strauss III and

1)Michele Boiani
Institutions: 1) Germline Development Group, Center for Animal Transgenesis and Germ Cell Research, The School of Veterinary Medicine, University of Pennsylvania, New Bolton Center, 2)Centre de Neurochimie, 3)Center for Research on Reproduction and Women's Health and 4)Female Germ Cell Biology Group

In the early mammalian embryo, the germline and soma are indistinguishable from each other. In the mouse, germ cell competence is induced at embryonic day 6.5 in proximal epiblast cells by signals emanating from the extra-embryonic ectoderm. Even during the specification period, precursor cells give rise to primordial germ cells and certain somatic cells, such as extra-embryonic mesoderm and allantois. The potential of embryonic stem (ES) cells to generate all lineages of the embryo in vivo has been widely reported in the literature, in striking contrast to the lack of data describing the derivation of germ cells from ES cells in vitro. We attributed the inability to demonstrate the derivation of germ cells from ES cells in culture to the lack of a suitable reporter system allowing for the non-invasive visualization of germ cell formation.

We show that mouse embryonic stem cells in culture can develop into oogonia that enter meiosis and recruit adjacent cells to form follicle-like structures and later develop into blastocysts. Oogenesis in culture should contribute to various areas including nuclear transfer, manipulation of the germline, and advance studies on fertility treatment and germ and somatic cell interaction and differentiation.