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Vertebrate reproductive science and technology
RESEARCH ARTICLE

From fibroblasts and stem cells: implications for cell therapies and somatic cloning

Wilfried A. Kues A B , Joseph W. Carnwath A and Heiner Niemann A
+ Author Affiliations
- Author Affiliations

A Department of Biotechnology, Institut für Tierzucht, Mariensee, D-31535 Neustadt, Germany.

B Corresponding author. Email: kues@tzv.fal.de

Reproduction, Fertility and Development 17(2) 125-134 https://doi.org/10.1071/RD04118
Submitted: 1 August 2004  Accepted: 1 October 2004   Published: 1 January 2005

Abstract

Pluripotent embryonic stem cells (ESCs) from the inner cell mass of early murine and human embryos exhibit extensive self-renewal in culture and maintain their ability to differentiate into all cell lineages. These features make ESCs a suitable candidate for cell-replacement therapy. However, the use of early embryos has provoked considerable public debate based on ethical considerations. From this standpoint, stem cells derived from adult tissues are a more easily accepted alternative. Recent results suggest that adult stem cells have a broader range of potency than imagined initially. Although some claims have been called into question by the discovery that fusion between the stem cells and differentiated cells can occur spontaneously, in other cases somatic stem cells have been induced to commit to various lineages by the extra- or intracellular environment. Recent data from our laboratory suggest that changes in culture conditions can expand a subpopulation of cells with a pluripotent phenotype from primary fibroblast cultures. The present paper critically reviews recent data on the potency of somatic stem cells, methods to modify the potency of somatic cells and implications for cell-based therapies.

Extra keywords: cell fusion, fate change, lineage commitment, reprogramming.


Acknowledgment

The authors acknowledge funding by the Deutsche Forschungsgemeinschaft (DFG).


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