Bone Marrow To Create Early-Stage Sperm Cells

GOETTINGEN, GERMANY - German scientists have used human bone marrow to create early-stage sperm cells, an initial step on the path to artificial development of human sperm. The disclosure was made in a paper by researchers at the University of Goettingen and other institutions that was published in the academic journal Reproduction on Friday.
Researchers said the breakthrough will help them understand more about how sperm cells are created, but warned that it could take years before they are used in fertility treatment.
Led by Professor Karim Nayernia, the research team took bone marrow from male volunteers and isolated stem cells previously found to grow into other body tissues such as muscle.
They cultured these cells in the laboratory and coaxed them into becoming male reproductive cells, which are scientifically known as "germ cells."
Genetic markers showed the presence of partly-developed sperm cells called spermatagonial stem cells, which are an early phase of the male germ cell development.
In most men, spermatagonial cells eventually develop into mature, functional sperm but this progression was not achieved in the experiment conducted by Nayernia and his team.
The professor, who now works at the North-east England Stem Cell Institute (NESCI), based at the Centre for Life in Newcastle upon Tyne, said it would take three to five years to grow the immature cells into fully developed sperm.
A lengthy process of scientific investigation is required within an ethical and social framework to be able say if it has potential applications in terms of fertility treatments in humans, he added.
Prof Nayernia gained international acclaim in 2006 when he and colleagues created sperm cells from mouse embryonic stem cells and used them to fertilise mice eggs, resulting in seven live births.
"We are very excited about this discovery," Nayernia said of his new research paper.
"Our next goal is to see if we can get the spermatagonial stem cells to progress to mature sperm in the laboratory and this should take around three to five years of experiments."
from Earth Times