Drug arouses UNC studies

Until recently, two options have been available for male contraception - condoms and vasectomies.

But new research stemming from UNC laboratories has discovered that a natural protein produces an immune reaction in the male reproductive system that, when made into an immunization, could work as a nonhormonal male contraceptive.

The shot would allow men to regain fertility after stopping treatment, and would not force them to rely on taking pills daily, wearing condoms, or getting a vasectomy - which usually proves irreversible.

"We've been interested in immuno-contraception for many years," said Michael O'Rand, a professor in the Department of Cell and Developmental Biology who led the project. "Since it works in monkeys, there should be no theoretical reason why it shouldn't work in men."

The experiment immunized male macacas monkeys with a form of eppin, a protein produced in the testis and epididymis. Monkeys that developed an immune response to the protein were not able to fertilize a female egg.

The protein causes the body's defense mechanism to disable the sperm. This occurs because the protein never enters the bloodstream, so when it is injected for the first time, the immune system does not recognize it and produces antibodies to fight it.

Stan Beyler, director of embryology and andrology laboratories, said this idea has been around for a while.

"The concept is not something brand new," he said. "It's just finding the right molecule. This could be the one."

Finding a way to help provide male contraception, Beyler said, also might help identify people with infertility disorders.

Sally Perreault, director of the reproductive toxicology division at the Environmental Protection Agency, said there have not been many reliable methods of birth control for men other than barrier methods such as condoms.

"I think this would serve a great need, allowing men to take responsibility and give couples more choice," Perreault said.

If the method is proven safe, effective and reversible, scientists could invent a safe male contraceptive.

However, the treatment will not be placed on the market anytime soon. "This is a long process," she said. "Clinical trials could take several years."

Beyler said that it is difficult to predict when the treatment will be placed on the market, and that much depends on funding.

"It needs to be recognized as something that is important and needs a substantial amount of funding and support," he said. "These are areas that we need to continue to strive to fund and research."

Contact the University Editor at udesk@unc.edu.