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From embryonic stem cells to blastema and MRL mice

Reproductive BioMedicine Online, 3, 16, pages 425 - 461

Abstract

New scientific knowledge offers fresh opportunities for regenerative medicine and tissue repair. Among various clinical options, multipotent embryonic stem cells (ESC) prepared from inner cell masses of rabbit blastocysts have been tested over many years. More recently, stem cells have been isolated from individual tissues and from umbilical cord blood. These methods seemingly offer similar rates of repair and avoid ethical complexities arising from the need for human embryos to prepare ESC. Different methods of regenerating tissues have now emerged, based on the well-known forms of organ regeneration in urodeles such as salamanders. These methods depend on the formation of a blastema, and recent studies on MRL mice have revealed that they possess similar methods of repair as in salamanders. There is also some evidence showing that this form of repair is also active in human fetuses but not in adults. Detailed knowledge of these various forms of tissue repair is now urgently needed in order to assess the benefits of each form of treatment. These matters are discussed at the end of this review where various investigations clarify the benefits and drawbacks of these varied approaches to tissue repair.

Keywords: blastema, embryonic stem cells, MRL mice, salamanders, tissue stem cells, urodeles.

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Professor Bob Edwards succeeded with colleagues in fertilizing the human egg in vitro in 1969. Then he applied IVF clinically with Patrick Steptoe working from Cambridge University, later establishing Bourn Hall Clinic. He has been awarded numerous honorary DSc degrees and published many scientific papers and books, including Conception in the Human Female, and A Matter of Life with Patrick Steptoe in 1980. Recent awards include the Lasker Clinical Medical Research Award (2001), Grand Hamdan Award for Clinical Science (2002), and the Pioneer in Stem Cells Award from Pittsburgh Development Center, USA (2004). In 2005 he won the highest award of the RCOG, the Eardley Holland Gold Medal. In 2006 he received the 30th Joseph Bolivar DeLee Humanitarian Award from Chicago Lying-in Hospital, as well as an Honorary Doctorate of Medicine from the Karolinska Institutet, Sweden. In 2007 he was honoured twice in France, becoming a Chevalier dans l'Ordre National de la Legion d'Honneur, and winning the Jacques Salat-Baroux Prize. He was also appointed Honorary Fellow of the Institute of Biology in the UK.

Footnotes

Chief Editor, Reproductive BioMedicine Online, Park Lane, Dry Drayton, Cambridge CB3 8DB, UK

* Correspondence