NEW YORK (Reuters Health) - As part of a 5-year multimillion-dollar federal biodefense grant, researchers at Wake Forest University School of Medicine in Winston-Salem, North Carolina are working on a vaccine against the plague, which is viewed as a potential agent for bioterrorism.
In Chicago, at the American Gastroenterological Association meeting -- part of Digestive Diseases Week -- Dr. Steven B. Mizel gave an update on their efforts. He reported that using flagellin protein, taken from bacterial flagella, as an adjuvant greatly enhances the effectiveness of plague vaccines.
According to the researcher, immunizing mice with just a piece of Yersinia pestis, the bacterium that causes plague, produces little if any immune response. When flagellin is added to the vaccine, antibody levels against the plague bacteria are 500,000-fold higher.
Mice immunized with the combination vaccine and challenged with a lethal dose of Yersinia pestis survived while control mice died within 3 days of challenge.
“We have also established that flagellin is an effective adjuvant in monkeys immunized with flagellin and a Yersinia pestis antigen,” Dr. Mizel said in a university statement, adding that the immunized monkeys “showed no undesired effects from the vaccine.” Studies are in progress testing whether the combination vaccine protects monkeys from Yersinia pestis challenge.
Prior immunity to flagellin does not appear to impair its ability to function as an adjuvant, Dr. Mizel also reports, noting that flagellin was as effective in mice with or without pre-existing antibodies against flagellin.
“This means that flagellin can be used multiple times with different vaccines,” he said. “These results clearly establish a strong foundation for the future use of flagellin as an adjuvant in humans,” he concludes.
MeSH Headings:Bacterial Proteins: Behavioral Sciences: Biological Warfare: Behavioral Disciplines and Activities: Flagellin: Social Problems: Social Sciences: Sociology: War: Anthropology, Education, Sociology and Social Phenomena: Psychiatry and PsychologyCopyright © 2002 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.
