Mice reversing male infertility through embryonic stem cell breakthrough

Researchers in Japan have moved a step closer to eliminating male infertility. They have used embryonic stem cells to grow healthy mouse sperm in the laboratory. It’s the breakthrough may people have been waiting for, a sign that using stem cells for regenerative medicine is possible.

Stem cells are the master cells of the body and the source of all cells and tissues. They can grow into different types of cells and tissues and because of that they are studied for use in all types of physiological applications: spinal cord repair, cardiac damage, diseased organs of any kind, and now reproductive obstacles like malformed sperm. In 2003 another team from Japan were able to transform embryonic cells into egg and sperm, but pregnancy never occurred. In 2006 they did it again but the mice that were produced from the embryonic cells were malformed and died.

Scientists at Kyoto University were able to remove stem cells from mouse embryos and then coax them into a precursor cell which would become either a sperm or egg. Once the sperm developed, it was transplanted into the testes of an infertile male mouse. The mouse eventually produced healthy sperm.

“The sperm were removed directly from the testes and fertilized with eggs (on laboratory dishes),” said lead author Mitinori Saitou, a professor Kyoto University’s department of anatomy and cell biology. “After insemination we made two set of embryos ad these were transferred into the uterus of the foster mother and they derived healthy mice (that went on to reproduce normally).”

Now that they know the precursor cell can be created and developed into viable sperm, the race is on to see who can take this to the next level with humans.

Source: Reuters, Medical News Today