Stem cells hold great promise for new treatments for many conditions as they
have the ability to become many different types of adult tissue. But at present
the most flexible type is found in human embryos - and their use is mired in
controversy.
A German team describes in the journal Nature how it isolated cells from
mice testes that seem equally useful. The researchers believe similar cells
could also be extracted from humans. Scientists already knew certain cells
in the testes of newborn mice were able, like embryonic stem cells, to generate
numerous different tissue types. But until now they had not been able to show
the same cells existed in adults.
The researchers, from the Georg August University in Gottingen, isolated
sperm-producing cells from the testes of adult mice. They were able to show
that, under certain culture conditions, some of them grew into colonies much
like embryonic stem cells. They called these cells multipotent adult germline
stem cells (maGSCs). Like ES cells, maGSCs can spontaneously differentiate
into the three basic tissue layers of the embryo - and contribute to the development
of multiple organs when injected into embryos.
Professor Chris Higgins, director of the Medical Research Council's Clinical
Sciences Centre, said: "The possibility of using cells from the testes as an
alternative to embryonic stem cells for therapy is intriguing. "However, much
more research is required before the similarities and differences between these
testes cells and embryonic stem cells are understood, and before their potential
for use in therapy can be properly assessed."
Professor Harry Moore, of the Centre for Stem Cell Biology at the University
of Sheffield, UK, said there were a number of key differences between mice
and human testes cells. Mice cells proliferated readily, but the same was not
true for human cells. There was also a significant difference in the chemicals
that each employed to grow.
However, he added: "Nevertheless, the paper offers an intriguing route for
future stem cell therapy which might overcome the use of embryos and cloning."
A Department of Health spokesperson said: "The government is investing £100m
in stem cell research over the next two years. "This includes research on all
types of stem cells - embryonic, umbilical and adult. "It is important we look
into all types of stem cells to make sure no opportunities for new treatments
are missed."
