Fertility hope as stem cell lab creates human sperm

SCIENTISTS have made medical history by using stem cell research to create human sperm.

The sperm, which was grown in a lab, may lead to future treatments for people who are infertile.

But it will not be used to create human babies – and will not mean the end of men, they said.

The breakthrough came when a team led by Professor Karim Nayernia at Newcastle University and the North East England Stem Cell Institute (NESCI) developed a new technique to grow sperm from embryonic stem cells.

Researchers saw the cells, which were treated with acid, begin to split and divide then eventually push out a tail and begin to move. They called for the introduction of laws “sooner rather than later” to control how the research is used.

Prof Nayernia said the development would lead to a better understanding of why infertility happened in men, and what caused it.

He said: “This understanding could help us develop new ways to help couples suffering infertility so they can have a child which is genetically their own.

“It will also allow scientists to study how cells involved in reproduction are affected by toxins, for example, why young boys with leukaemia who undergo chemotherapy can become infertile for life – and possibly lead us to a solution.”

The team also believe that studying the process of forming sperm could lead to a better understanding of how genetic diseases are passed on.

In the technique developed at Newcastle, stem cells with XY chromosomes (male) were developed into germline stem cells which were then prompted to complete meiosis – cell division with halving of the chromosome set. These were shown to produce fully mature, functional sperm called In Vitro Derived sperm (IVD sperm).

In contrast, stem cells with XX chromosomes (female) were prompted to form early-stage sperm, spermatagonia, but did not progress further. This demonstrates to researchers that the genes on a Y chromosome are essential for meiosis and for sperm maturation.

The IVD sperm would not and could not be used for fertility treatment. As well as being prohibited by British law, the research team say fertilisation of human eggs and implantation of embryos would hold no scientific merit for them as they want to study the process as a model for research.

He said: “While we can understand that some people may have concerns, this does not mean that humans can be produced ‘in a dish’ and we have no intention of doing this.

“This work is a way of investigating why some people are infertile. If we have a better understanding of what’s going on it could lead to new ways of treating infertility.”

The work is published today in the academic journal Stem Cells and Development.