Researchers make sperm from stem cell in dish

（单词翻译）

 WASHINGTON, Aug. 4 (Xinhua) -- Researchers have found a way to turn mouse embryonic¹ stem cells into sperm² and this finding opens up new avenues for infertility³ research and treatment, according to astudy published Thursday in the online edition of journal Cell,

A Kyoto University team coaxed⁴ mouse embryonic stem cells into sperm precursors⁵, called primordial⁶ germ cells (PGCs), and shown that these cells can give rise to healthy sperm. The researchers say that such in vitro reconstitution of germ cell development represents one of the most fundamental challenges in biology.

When transplanted into mice that were unable to produce sperm normally, the stem cell derived⁷ PGCs produced normal-looking sperm, which were then used to successfully fertilize⁸ eggs. These fertilized⁹ eggs, when transplanted into a recipient¹⁰ mother, produced healthy offspring that grew into fertile male and female adult mice. The same procedure could produce fertile offspring from induced pluripotent stem cells that are often derived from adult skin cells.

"Continued investigations¹¹ aimed at in vitro reconstitution of germ cell development, including the induction¹² of female primordial germ cell-like cells and their descendants, will be crucial for a more comprehensive understanding of germ cell biology in general, as well as for the advancement¹³ of reproductive technology and medicine," the researchers wrote.