DURHAM, N.C.--Researchers have noticed a curious phenomenon in sub-Saharan Africa: many female prostitutes who come in contact with men infected with HIV do not themselves become ill.
Further study of these women shows that the mucous lining their vaginas contains HIV-specific secretory immunoglobulin A (IgA) antibodies that may be able to stop the virus and keep it from entering the bloodstream. It is possible these women have become "naturally" immunized against future HIV infections. A research team led by Duke University Medical Center is hoping to use this knowledge to create a vaccine that could stimulate similar responses in the uninfected. Additionally, they plan to employ a novel delivery system that can be easily used in underdeveloped nations.
Project leader Dr. Bart Haynes, chairman of the department of medicine at Duke, believes that the team will develop a vaccine that can be delivered nasally and would stimulate immune responses in the user at both the mucosal and systemic levels.
"I think we will be able to start testing our next generation of candidate vaccines in humans in a couple of years," said Haynes -- a time-span that seems to be just around corner considering he has spent 15 years studying the virus. "Making a vaccine has turned out to be more difficult than we ever believed. The virus is more complex than we thought and is very cunning in its ability to subvert our immune systems. However, there will be a vaccine." To prove the merit of this approach, the National Institutes of Health is supporting the research in the amount of $5.5 million over the next five years. According to a recent report by the U.S. surgeon general, of the estimated 33.4 million people worldwide who are infected with HIV, 22.5 million live in sub-Saharan Africa, 6.7 million in South and Southeast Asia, and 1.4 million in Latin America. By comparison, there are about 665,000 infected in the United States.