Stephen Crohn, who was known as “The Man Who Can’t Catch AIDS” due to his shocking immunity to HIV, committed suicide on August 23; he was sixty-six.
A resident of New York, Crohn’s unique resistance to the virus helped doctors gain a more thorough understanding of HIV; as they discovered, his CD4 white blood cells, which are normally invaded by HIV at the start of infection by the disease, locked the virus out. Crohn allowed doctors to expose his white blood cells to HIV, and they found they were unable to cause an HIV infection—even when they used a concentration of the virus thousands of times stronger than would be possible naturally.
The reason for his immunity, the medical community eventually learned, was because HIV enters white blood cells via working its way into two receptors. The second of Crohn’s receptors was flawed due to a genetic defect, known as the “delta 32” mutation on the CCR5 receptor; the defect is found in less than one percent of the population. As Crohn’s boyfriend, gymnast Jerry Green, was among the first people to contract HIV and died of AIDS in 1982, the mutation saved Crohn’s life.
He was named as “The Man Who Can’t Catch AIDS” by The Independent, which ran a story on him in 1996. Over the years, Crohn told his story for newspapers and documentaries all over the world.
It was only announced on September 13 that he had committed suicide. According to the New York Times, his sister, Amy Crohn Santagata, said that “My brother saw all his friends around him dying, and he didn’t die. He went through a tremendous amount of survivor guilt about that.” But, she added, during the height of the crisis, he said to himself, “There’s got to be a reason.”
The director of the Ragon Institute of Massachusetts General Hospital, MIT, and Harvard, Dr. Bruce D. Walker, said “What he contributed to medical knowledge is really quite extraordinary.”
What researchers learned from Crohn led, among other breakthroughs, to the drug maraviroc, an antiretroviral that inhibits HIV from spreading in patients by blocking the CCR5 receptor, just as Crohn’s immune system did naturally. In 2006, Timothy Ray Brown became the first person declared cured of AIDS after a bone marrow transplant from a donor with the same mutation.
In 1996, Crohn told The Independent that if his blood could reveal something vital in the battle against AIDS, it “would be very touching to me.”