Scientists have grown sperm in the laboratory in a landmark study that could help preserve cancer patients’ fertility and shed fresh light on male reproductive problems.
Fertility experts said it was a “crucial experimental advance” towards the use of lab-grown sperm in the clinic and a step nearer to routine creation of sperm for those who cannot make the cells normally.
Sperm grown in the laboratory, if proved safe, could be used to help infertile men have children through IVF treatments. The procedure could also benefit boys with cancer who are too young to produce sperm but are at risk of being made infertile by radio or chemotherapy. The latest research suggests boys could have testicular tissue removed and kept in cold storage for later use.
Japanese researchers cultivated small pieces of tissue from the testes of baby mice on a gel bathed in nutrients. After several weeks they collected viable sperm from the tissue. The sperm appeared to be healthy and was used in IVF treatments to produce 12 live mice that went on to have young of their own. Seven of the mice were born after sperm heads were transferred into 23 eggs using a technique called round spermatid injection and another five were born after 35 eggs were fertilised using intracytoplasmic sperm injection, a common IVF procedure.
The scientists retrieved healthy sperm from tissue cultivated after being frozen for up to 25 days, suggesting that cold storage did not harm the cells. The work, reported in the journal Nature, is the most successful attempt yet to grow mammalian sperm from testicular tissue.
“One of the problems I face, as a urologist, is that we do not have any effective ways to treat patients suffering from male infertility due to defective or insufficient sperm production,” said Takehiko Ogawa, who led the study at Yokohama City University’s graduate school of medicine. Using the technique, he said, scientists would be able to study sperm production in detail and help elucidate the glitches that cause infertility.
In an accompanying article Marco Seandel and Shahin Rafii at the Weil Cornell Medical College in New York said the work was “a crucial experimental advance along the thorny path to the clinical use of sperm” grown in the lab.
Allan Pacey, a senior lecturer in andrology at Sheffield University, England, said: “This could help discover drugs or treatments to stimulate infertile men to produce more or better sperm. It also may help preserve the fertility of males.” — Guardian News & Media 2011