An Amazing Human Being
As good as he is at teaching, Pfefferkorn insists that his first love is medical research. Growing up as an only child in Manitowoc, Wisc., he knew as far back as he can remember that he wanted to go into medicine. Neither of his parents were either scientists or doctors, but his father did subscribe to a magazine that young Elmer, already a strong student in math and science, read eagerly—Popular Science.
After graduating from Lawrence College in Wisconsin, he got a Rhodes Scholarship to study medicine at Oxford. There he fell in love with research while working in the lab of Dr. Donald Woods, an eminent bacteriologist known for discovering the mechanism of how sulfonamides work against bacteria. At Harvard Medical School, Pfefferkorn resolved to go into research, did a thesis on the genetics of bacteriophages (viruses that infect bacteria), and by 1959 had earned his Ph.D.
He decided he'd like to work on polioviruses next. "I went to one of the greatest virologists at Harvard—John Enders," says Pfefferkorn, "and I told Dr. Enders that I intended to be a virologist and I was going to work on poliovirus." Enders was one of three people who'd been awarded the 1954 Nobel Prize in Physiology or Medicine for the cultivation of the poliomyelitis virus. "Wise John Enders said to me that there [were] already too many people working on poliovirus. He suggested that it would be much wiser to work on a virus that no one knew anything about."
Pfefferkorn wound up working on an infectious organism that one of Enders's postdoctoral fellows had isolated from a mosquito in Egypt: the Sindbis virus, named for a region near Cairo. "All it had was a name," recalls Pfefferkorn. "Nothing was known about it. [John Enders] dug a sample out of his freezer and said that this would be an appropriate
Whenever he gets a chance, Pfefferkorn waxes eloquent about toxoplasma. He's intrigued by how well the parasite avoids being destroyed by the body's immune system. "Oh, it's a perfectly marvelous organism," he says.
way to begin a career in virology. And he was dead right."
Pfefferkorn spent the next 10 years working on Sindbis—at Harvard and later at Dartmouth after his move north in 1967. "It rapidly became a model systemfor studying animal viruses," he says. "Laboratories all over the world began working on this virus and building on the experiments we did."
But in the 1970s, when he was close to identifying the role of each gene in Sindbis, Pfefferkorn "decided to stop being a virologist because the field was getting much too crowded," he recalls. "If I had been talking to a young virologist-to-be, as the old master fulfilling John Enders's role, I would have said, 'Don't work on this virus. There are too many people working on it already.' So I essentially gave the same advice to myself, and I decided to switch completely and become a parasitologist."
Pfefferkorn focused on Toxoplasma gondii, a parasite that behaves like a virus. T. gondii grows inside cats and other mammals and is spread through feces. The disease it causes—toxoplasmosis—can cause neurological damage in AIDS-compromised individuals as well as in unborn children, since the infection can cross the placental barrier.
"Elmer was a pioneer in introducing the rigorous biological approach to study this interaction between the parasites and its host cell," says Joe Schwartzman, who returned to DMS a few years after graduating to do a fellowship in Pfefferkorn's lab. Pfefferkorn even convinced Dr. David Bzik, a DMS malaria researcher who had trained as a virologist, to switch to studying T. gondii because it was a better surrogate model for genetic studies.
Whenever he gets a chance, Pfefferkorn waxes eloquent about toxoplasma. He's