Potential for a better smallpox vaccine
The smallpox results, which appear in the February issue of Clinical Vaccine Immunology, could lead to an effective human vaccine against smallpox that is safer than the present live-vaccinia virus vaccine because it would use nanoemulsion-killed vaccinia virus, says Baker.
Anna U. Bielinska, Ph.D., a research assistant professor in internal medicine at the U-M Medical School, and others on Bakers research team developed a killed-vaccinia virus nanoemulsion vaccine which they placed in the noses of mice to trigger an immune response. They found the vaccine produced both mucosal and antibody immunity, as well as Th1 cellular immunity, an important measure of protective immunity.
When the mice were exposed to live vaccinia virus to test the vaccines protective effect, all of them survived, while none of the unvaccinated control mice did. The researchers conclude that the nanoemulsion vaccinia vaccine offers protection equal to that of the existing vaccine, without the risk of using a live virus or the need for an inflammatory adjuvant such as alum hydroxide.
We found that the nanoemulsion vaccine could inactivate and kill the virus and then subsequently induce immunity to the virus that includes cellular immunity, antibody immunity and mucosal immunity, Baker says.
In antibody immunity, antibodies bind invading microbes as they circulate through the body. In cellular immunity, the immune system attacks invaders inside infected cells. There is growing interest in vaccines that induce mucosal immunity, in which the immune system stops and kills the invader in mucous membranes before it enters body systems.
A National Institutes of Health program, the Great Lakes Regional Centers of Excellence for Biodefense and Emerging Infectious Diseases, funded the research. If the federal government conducts further studies and finds the nanoem
|Contact: Anne Rueter|
University of Michigan Health System