Wednesday, July 8, 2009

Human sperm created from stem cells in world first, claims British university

British scientists have created human sperm using stem cells in a medical first that could revolutionise fertility treatment, they claim.

Researchers at the pioneering Northeast England Stem Cell Institute say they have made the breakthrough using stem cells from an embryo.

They claim that with some minor changes the sperm could theoretically fertilise an egg to create a child.
Within 10 years, the scientists say the technique could also be used to allow infertile couples to have children that are genetically their own. It could even be possible to create sperm from female stem cells, they say, which would ultimately mean a woman having a baby without a man.

This is the first time human sperm has been created anywhere in the world in a laboratory. However, the experiment has proved controversial, threatening to reopen the fierce debate over embryo research.

Last night, the scientific community was divided over its merits, with campaigners questioning the ethics and fellow scientists querying its validity, despite describing the work itself as 'very important'.

The medical breakthrough, which is reported in the respected journal Stem Cells and Development, is the latest from the institute, which is made up of the Newcastle and Durham Universities along with the Newcastle NHS Foundation.

Led by the leading stem cell biologist Professor Karim Nayernia, the team has already used the technique in mice which have then gone on to produce offspring.

Professor Nayernia, who is calling for a debate on the use of his breakthrough, said the sperm created was not perfect but had all the essential qualities for creating life.

He said: "This is very amazing and very exciting. They have heads, they have tails and they move. The shape is not quite normal nor the movement, but they contain the proteins for egg activation."

In the technique developed at Newcastle University, stem cells with XY chromosomes – containing both male and female characteristics – were developed.

A laser was used to separate and isolate the male stem cells and they were then grown in a dish. Researchers saw the cells split and divide, then eventually push out a tail and head and begin to move.

These were shown to produce fully mature, functional sperm, they say.

Professor Nayernia said the work was in its early stages and more investigation was needed to decide whether such sperm would be safe or suitable as a fertility treatment – although this is currently against the law.

The mice in his earlier experiment all died shortly after they were born.

However he said he believed that within a decade such a treatment could be offered to, for example, young boys who had received chemotherapy which can leave them infertile.

"Soon we will be able to isolate stem cells from the skin to generate sperm cells," he said. "This would enable us to look at individual stem cells from an infertile patient and find out what is the cause.

"We hope that eventually this could help create sperm for infertile men."

He called for a debate on the subject before the science overtook the law.

"You can use all technology in the right way or the wrong way," he said. "This is the case in all new technology. Nuclear power can be used for electricity or the bomb for example.

"This should be decided not by scientists but by the law which is not our responsibility. Our responsibility is to provide treatments for infertile people. The test tube babies are now routine but it was controversial at the time."

It is estimated one in seven UK couples have difficulty conceiving – about 3.5 million people. In about a third of all couples having IVF, male fertility is a contributory factor.

Under the Human Fertilisation and Embryology Act 2008, using artificial sperm and eggs in fertility treatment is banned. It is legal to create sperm in the laboratory but to combine it with an egg to create an embryo for scientific research requires a licence. Even then the embryo must be destroyed within 14 days.

There is an absolute ban on the use of artificial sperm and eggs used in fertility treatment as the HFEA scientists believe there are still "significant safety concerns". The ethical concerns have yet to be decided on.

Some experts cast doubt on the claims from Newcastle, arguing that the cells did not constitute "authentic" sperm with all the necessary biological characteristics.

Dr Allen Pacey, senior lecturer at the University of Sheffield, said "It potentially could be a breakthrough, and I hope it is, but for me the jury is still out.

"It would be really good to be able to do this. I am very supportive of this kind of research."

Sarah Norcross, Director of the UK assisted conception and genetics charity the Progress Educational Trust, said: "The latest developments in creating in vitro derived sperm are exciting, as they point to a possible future where fertility can be restored to men who cannot produce sperm in vivo. While this solution is still a way off, it gives hope to males whose fertility is compromised and who wish to have a child who shares their genes. This would be a novel way to solve the shortage of donor sperm in the UK."

Professor Robin Lovell Badge, Medical Research Council National Institute of Medical Research, said the research was still far from perfect but offered real potential.

"Despite these drawbacks, it may be that the authors have made some progress in obtaining sperm from human Embryonic Stem cells in vitro," he said. "This will be very important for research and ultimately, although definitely not yet, for fertility treatments. "

Dr Evan Harris MP, who tabled amendments to the 2008 bill on laboratory-made eggs and sperm said: "While the Newcastle team is not seeking at present to use stem cell derived sperm as a treatment for infertility, it is clearly a possible future application."

Josephine Quintavalle, director of Comment on Reproductive Ethics, said that the research was "totally wrong".

"This is man at his maddest," she said. "I think that sometimes we have to stop meddling and accept infertility. Science must be totally ethical and totally safe – this is neither."

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