Study: Can sperm mimic embryo stem cells?

WASHINGTON, Nov. 16 (UPI) -- Researchers at University of Texas Southwestern University said this week they are close to getting sperm cells to act like embryonic stem cells.

The UT Southwestern scientists say they have devised methods to keep male rat germ-line stem cells, or sperm precursor cells, from differentiating, or changing permanently into sperm.

The study is a critical step in coaxing such cells to behave like embryonic stem cells, the researchers said in a statement, which might eventually make sperm cells a viable alternative to embryonic cells in genetic therapy.

"We're only one step removed from another major step, the Holy Grail for us certainly, which is pushing these cells back a level to a state that is pluripotent-like, similar to embryonic stem cells. That's what we're focused on now," said David Garbers, professor of pharmacology at the university and senior author of a study to appear in an upcoming issue of the Proceedings of the National Academy of Sciences.

The researchers said they also froze the sperm stem cells, thawed them and transplanted them back into rat testes, where they developed into normal sperm.

The research has other potential applications, including the development of new male contraceptives and new animal models to test stem-cell-based therapies.

Embryonic stem cells are capable of growing into different types of cells in the body, and scientists hope to eventually harness them for use in replacing damaged or diseased tissue.