Sperm: The Final Frontier

On the second flight, Atlantis approached an area over Australia where the shuttle would temporarily lose radio contact. Thirty seconds before losing the signal, Houston's controller called Tash to see what he wanted to do: Tash needed to tell astronaut Edward Lu whether to keep going with the precisely timed experiment, but Tash was too focused on his own work. Atlantis headed toward the dead zone.

The voice from Houston began counting down — 10, nine. Tash froze. He was worried that, without audio and video feeds, his team wouldn't be able to replicate Lu's work two hours later.

"Wait," he told Houston's controller. But it was too late. He heard only crackling. Eight minutes passed, then 10. Then Tash heard Lu's voice: "Atlantis."

Lu had waited. The experiment was still on track. And it occurred to Tash that he'd just experienced something that happens to few men: NASA had asked him what an astronaut should do.

For the NASA experiments, Tash had designed a way to study how a series of proteins and enzymes regulated sperm's movements. When they first start to swim, reactions occur faster, he found. But then they respond more slowly to influences from the egg. The experiment led to startling results that suggested fertilization in space might be difficult.

The flights were productive for Tash: Five published papers came out of the research, as well as a book chapter, nine published abstracts, formal seminars at national and international scientific meetings, and a patent.

Sitting in LattéLand, Tash reveals that his work with NASA changed him.

"I was crossing the line between science and a spiritual experience," he says.

At night at Cape Canaveral, he would look up at the stars and realize that somewhere up in space were his fingerprints.

"I just felt," he says, "part of something so big." On the NASA project, Tash learned other personal lessons. He had to rely on everyone from the astronauts who performed his experiments to the earthbound techs who fueled the space shuttle's tanks. It gave him a new appreciation for the fact that he couldn't do his work alone.

That was his frame of mind when, in May 2000, the National Institutes of Health offered a $3 million grant for work on male contraceptives. There was a catch: The lead researcher would have to be a medicinal chemist, not a reproductive biologist like Tash. "Previous approaches weren't even going to be considered," he says.

As it happened, there was a noted medicinal chemist on the KU campus in Lawrence. Gunda Georg is one of the country's most prominent pharmaceutical researchers. She's renowned — and well-funded by the NIH — for her work on cancer-treating drugs.

When Georg got the NIH's letter announcing its request for proposals, she asked around and discovered Tash in Kansas City. "Since he had been involved in the biology of male reproduction for such a long time," she says, "he made very good suggestions about things we could work on together."

But Georg recalls that Tash was skeptical. "It's very tough to get money from the NIH," she says in a German accent. "From day one, I said to him, 'There is nobody who can beat us as a team.' Because it's very unique: someone like myself, who has a really good track record in the field of medicinal chemistry, and then someone who is a reproductive biologist specializing in the male reproductive system. That was exactly what the NIH wanted."

Tash was on board. They got the contract in March 2001.

Georg knew about the cancer-fighting drug lonidamine, which has a side effect of blocking sperm production. The problem was other side effects: muscle pain and damage to the liver and kidneys. That might be acceptable for a cancer patient who faces death without treatment, but not for a healthy male. The Population Council, in its 20-year effort to find a male contraceptive, had developed a couple of lonidamine variations that had fewer side effects but weren't very potent contraceptives. Researching the Population Council's patent, Georg discovered a part of lonidamine that no one had researched. She and Tash believed they could play with that molecule to create a drug that blocked the sperm production but didn't cause damaging side effects.

A year and a half later, in November 2002, they'd synthesized more than 150 chemical variations of the compound. One looked especially promising. They called it simply RC-MC-110 and began testing it on male rats.

It worked better than they had imagined. Microscopic cross-sections of the rats' testes showed no sperm.

Thrilled by their discovery, the NIH asked Tash and Georg to supply enough doses to send to independent researchers, who would try to confirm the results.

As the next year passed, Tash and Georg realized that the feds were conducting wide-ranging experiments that went way beyond their own — testing the potency of various oral doses and percentages of reversibility. And the NIH's contractors went on to the next step: giving doses to male rats and putting them in cages with females to see what would happen.