Trials on mice have revealed that the production of stem cells can be stimulated through drug therapy. Furthermore, it was observed that by varying the regime of administered drugs, the type of stem cells produced could be controlled.
This approach to stimulating stem cell production has been used in clinical trials on humans. Specifically, it has been used to promote the release of blood stem cells (haematopoietic stem cells) in sufferers of lymphoma. These latest trials suggest that it may be possible to stimulate the human body to generate other types of stem cells.
Researchers at Imperial College London treated mice with a natural growth factor before administering the drug Mobozil. Mobozil allows stem cells to be released from the bone marrow into the bloodstream. When the administration of Mobozil was preceded by treatment with granulocyte colony stimulating factor (GCSF), the levels of haematopoietic stem cells within the mice increased. However, the treatment of mice with vascular endothelial growth factor (VEGF) stimulated the production of mesenchymal stem cells (MSCs) and epithelial progenitor cells (EPCs). While MSCs aid the regeneration of tissue and bone, EPCs stimulate the growth and repair of blood vessels.
An interesting observation from the trials was that the two treatments were mutually exclusive. The GCSF treatment did not stimulate the production of MSCs and EPCs; the VEGF treatment did not stimulate the production of haematopoietic stem cells.
Drug therapies such as this could allow the medical profession to utilise the healing potential of stem cells without the ethical dilemma of sourcing stem cells from embryos.
Robert Lanza from Advanced Cell Technology in the USA said, “The ability to selectively stimulate a patient’s own stem cells could be a powerful tool for treating disease, and to speed up the repair of damaged and worn out tissues.” However, he also raised the point that the trials were carried out on mice, meaning there is no guarantee that the techniques will be viable in humans.
References
Coghlan, A. (2009). Drugs unlock the body's own stem cell cabinet. http://www.newscientist.com/article/dn16383-drugs-unlock-the-bodys-own-stem-cell-cabinet.html (Accessed 15 March 2009).
