MEDICINE: Lives of Spirit and Dedication

The world pays tribute to eleven who stirred emotions and laid foundations MEDICINE

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It sounds like vintage Hollywood. Driven from the university by Italy's Fascists just before World War II, a brilliant young Jewish biologist persists in her pioneering research into the nervous system, using makeshift equipment in a farmhouse bedroom. Food is so scarce that after experimenting on chicken embryos, she whips the leftover yolks into omelets. But she perseveres. Invited to work in the U.S. after the war, she meets a young biochemist, and together they launch a new field that promises hope for everything from cancer to burns.

Last week provided a dramatic climax to this improbable real-life tale as Dr. Rita Levi-Montalcini, 77, now with the National Council of Scientific Research in Rome, and Stanley Cohen, 63, at Vanderbilt University in Nashville, won the 1986 Nobel Prize for Physiology or Medicine. The pair, who met in St. Louis in 1953 at Washington University, found the first of the body's many "growth factors": proteins that guide the development of immature cells. Said Nobel Committee Member Kerstin Hall: "Every single discovery in the field of cell growth factors has followed closely in the footsteps of Levi-Montalcini and Cohen."

From her earliest experiments, Levi-Montalcini, who holds both Italian and American citizenship, focused on the nervous system. Before her discovery, scientists did not understand how organs signaled developing nerve cells to link up with them. It was Levi-Montalcini who first suggested in 1951 that the signal might come from a growth-stimulating chemical in the cells targeted by the nerves. Her hunch was confirmed in 1952 when she observed that single nerve cells, taken from chick embryos and cultured with tissue from mouse tumors, sprouted nerve fibers that reached out "like the rays of the sun." Her conclusion: there was growth factor in the tumor tissue.

Subsequent experiments showed that the mysterious substance was also present in snake venom and mouse salivary glands. It was left to Cohen, a pipe-smoking individualist, to extract the first pure samples of the protein now known as nerve growth factor. Later, working separately, Cohen discovered epidermal growth factor, which governs cell development in the skin. He also located a protein on the surfaces of cells that acts as a receptor for EGF.

While little is known about how growth factors work, there is no doubt of their importance. Doctors at Harvard Medical School use EGF to grow skin for grafting onto burn patients. Other growth factors may hold important clues about cancer and Alzheimer's disease. Cohen seemed surprised by the Nobel award. "You just keep on trying to find things," he said. "I'm very happy that the work we've been doing the last 25 to 30 years turned out to be important."

For Levi-Montalcini, the award assuaged memories of earlier frustrations. "Once Italy was not a country for research," she said in Rome. "Now, suddenly, things have changed, and this makes me immensely happy."