This could really hurt!
Key to future stem cell production may lie inside the testicles
· Tissue is rich in formative cells, British scientists say
· New source would avoid need to destroy embryos
Ian Sample, science correspondent
Tuesday June 6, 2006
The Guardian
British scientists have been granted permission to investigate whether stem cells found deep inside testicles can be used to repair damaged tissues and organs.
Researchers led by fertility specialist Robert Winston at the Hammersmith hospital in London will pluck cells from testicular tissue to see if they are as versatile as embryonic stem cells, which can potentially grow into any tissue in the body.
If the scientists succeed in harvesting the cells and keeping them alive, they could pave the way for powerful new therapies for conditions as diverse as heart disease, Parkinson's and spinal cord injuries, without the need to destroy human embryos to collect them. The work has been given the green light by the Human Fertilisation and Embryology Authority.
Embryos used in stem cell research are either donated from fertility clinics or created using therapeutic cloning, a practice some critics condemn as unethical and disrespectful to life because the embryo is destroyed in the procedure. In practical terms there is also a shortage of human eggs needed to make cloned embryos.
The scientists believe 0.3% of tissue in the testes is made up of stem cells, one of the highest counts in the body. "We've been tinkering with the testes for a year or two now, but what we don't know yet is how reliably we can get stem cells from them," said Lord Winston.
The HFEA licence allows the team to grow testicular cells alongside embryonic cells to see if they develop in the same way and show the same medical potential. The next step will be to nudge the cells into forming different tissue types, such as brain or heart cells. In future a man could bank testicular tissue early in life and use it years later to repair damaged or diseased organs, without the risk of rejection.
Cambridge University has estimated 150 different stem cell lines would be enough to grow tissue matching around 90% of the population, male and female.
Earlier this year, Gerd Hasenfuss, a researcher at the Georg-August-University in Göttingen, caught the attention of stem cell scientists around the world when he discovered that cells collected from mouse testicles could be grown into tissue types including heart, brain and skin cells.
Harry Moore, professor of reproductive biology at Sheffield University, welcomed the study. "In this country, the ethical issues of obtaining stem cells from cloned embryos are really covered by the HFEA, but there is still the major problem of where do you get eggs that are high enough quality and in sufficient quantity. The advantage of this work is that it avoids both of those issues," he said.
"It might not sound very appealing to men, but it isn't actually as traumatic as it sounds."
Professor Chris Barratt, scientific director of the Assisted Conception Unit at the Birmingham women's hospital, said: "There are a lot of testicles around and you don't need a staggering number to have enough variety to match nearly all of the population."
"If the facts don't fit the theory, change the facts."
