Scientists use skin cells to create artificial sperm and eggs

Scientists have made primitive forms of artificial sperm and eggs in a medical feat that could transform the understanding of age-related diseases and fertility problems.

Researchers in Cambridge made the early-stage sex cells by culturing human embryonic stem cells under carefully-controlled conditions for a week.

They followed the success by showing that the same procedure can convert adult skin tissue into precursors for sperm and eggs, raising the prospect of making sex cells that are genetically matched to patients.

The cells should have the potential to grow into mature sperm and eggs, though this has never been done in the lab before. The next step for the researchers will be to inject the cells into mouse ovaries or testes to see if they fully develop in the animals.

British law prohibits fertility clinics in the UK from using artificial sperm and eggs to treat infertile couples. But if the law was revised, skin cells could potentially be taken from patients and turned into genetically identical sperm or eggs for use in IVF therapies.

Skin cells from a woman could only be used to make eggs because they lack the Y chromosome. Those from a male might theoretically be turned into eggs as well as sperm, but Azim Surani, who led the work at the Gurdon Institute in Cambridge, said that on the basis of current knowledge, that was unlikely.

Its not impossible that we could take these cells on towards making gametes, but whether we could ever use them is another question for another time, Surani told the Guardian.

Researchers have made sperm and eggs from rodent stem cells before but have struggled do the same with human cells. In 2012, Japanese scientists created mouse eggs from stem cells and used them to make baby mice. Three years earlier, scientists at Newcastle University claimed to have made human sperm from stem cells, but their scientific paper was retracted amid allegations of plagiarism. In 2002, US researchers produced male and female mouse pups from male stem cells.

Suranis team tried a number of different approaches before hitting on a culture process that turned up to half of the human stem cells in the dish into precursors of sperm and eggs. Over the five day process, the scientists added natural chemicals called growth factors to nudge the cells in the right developmental direction.

Its remarkably fast. We can now take any embryonic stem cell line and once we have them in the proper conditions, we can make these primordial cells in five to six days, Surani said. Details of the work, a collaboration with the Weizmann Institute in Israel, are published in the journal, Cell.

Excerpt from:
Scientists use skin cells to create artificial sperm and eggs