Posted on 03/24/2006 8:32:43 PM PST by hocndoc
Mice testicles yield 'ethical' stem cells
* 16:22 24 March 2006 * NewScientist.com news service * Andy Coghlan
Mens testicles may provide an ethical source of embryonic stem cells (ESCs), suggest new experiments in mice.
A team in Germany has successfully grown mouse ESC-like cells from spermatagonial stem cells which normally turn into sperm. The ESC-like cells can be grown into all tissues of the mouse body, suggesting that if the same could be done in men, it would provide patients with a source of tissue-matched cells for repairing any damaged organs or tissue.
So far, all existing colonies of human ESCs have been derived from surplus human embryos, leftover from infertility treatments. Because a human embryo is sacrificed in the process, many religious groups oppose such research, especially in the US where President George W Bush has placed heavy restrictions on federal stem cell researchers.
The discovery that cells which behave like ESCs can now be obtained from adult mice may now open up the possibility of a similar ethical source from grown men.
Were in the process of doing this in humans, and were optimistic, says Gerd Hasenfuss of the Georg-August University of Göttingen, Germany, and head of the team which pioneered the breakthrough. Tissue choice
Hasenfuss and his colleagues first extracted spermatagonial stem cells from adult mouse testes, before growing them in the lab in a special mixture of growth factors and nutrients which coaxed the cells into becoming ESC-like cells instead of sperm.
We can turn these into all kinds of tissue, from beating cardiac and vascular cells to neurons, skin cells and liver cells, says Hasenfuss. And the process worked in 27% of the mice they experimented on.
Although the cells behaved like ESCs in tests, the team have decided to call them multipotent adult germline stem cells to distinguish them from their embryonically-derived counterparts.
I think it will solve the ethical problem if you can generate cells from adult humans, says Hasenfuss. He told New Scientist that his team is already taking testicle-tissue samples under consent from patients undergoing operations for other conditions, such as cancer.
Its rather painful, and is usually done under general anaesthetic, but its routinely done to gain sperm for IVF, for example, so its a well-known procedure, says Hasenfuss. He notes that the cells would not be obtainable from a sperm or semen sample. It has to be a biopsy. Leap to humans
Although forbidden by law in Germany from obtaining ESCs from embryos, or even working on ESCs derived from the same source in other countries, Hasenfuss backs research on both sources from adults and embryos.
To circumvent the ethical objections, his team has attempted for years to derive ESCs from adult tissues, and the testicular source is only success so far. ESCs were obtained from embryonic mice in 2004 by Mito Kanatsu-Shinohara and his colleagues at Kyoto University, Japan, but Hasenfuss says he is the first to get them from adult mice.
Other researchers welcomed the findings. On the basis of what I see, I couldnt discount what they say theyve achieved, says Paul de Sousa at the University of Edinburgh, UK. The real news is the capacity to sustain these cells in culture and retain their ability to turn into all tissue, he says.
But it may be a leap of faith to apply it in humans, de Sousa cautions. I would be wary that things in humans would be as simple.
Journal reference: Nature (DOI: 10.1038/nature04697)
medipinger!@#
BTTT
Whether possible or not, I believe that there are two ways of doing something; morally or immorally.
Too many people have a vested interest in the latter regarding this type of research.
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