First Vaccine Developed That Protects Against SIV In Monkeys.(simian immunodeficiency virus)

2001 AUG 15 - (NewsRx.com & NewsRx.net) --

University of California scientists have developed the first vaccine that protects against vaginal transmission of a virus closely related to HIV.

In studies with monkeys, all vaccinated animals remained healthy a year after exposure to virulent simian immunodeficiency virus (SIV) that normally causes AIDS-like disease within a year.

Results have prompted plans for human clinical trials with an HIV version of the vaccine. Like the SIV version, the HIV vaccine will combine elements of the highly successful Sabin oral poliovirus vaccine with genetic fragments of HIV. The Sabin vaccine triggers a robust immune response which extends to piggybacked HIV particles, the scientists found.

Because sexual intercourse is the route of transmission in more than 80% of HIV infections worldwide, many experts believe the best chance to prevent the spread of HIV infection is by building up an immunological barrier at the port of entry: the mucosal surface of the genitals or rectum. But most vaccines tested so far don't consistently induce a strong immune response against HIV at this critical line of defense. The new vaccine takes advantage of the Sabin live poliovirus vaccine's trait of triggering a broad, long-lasting immune response at the mucosal surface.

The vaccine, administered by nose drops, was developed at the University of California, San Francisco (UCSF), and tested at UC Davis. Raul Andino, PhD, UCSF associate professor of microbiology and immunology conceived of the recombinant vaccine technology, along with Mark B. Feinberg, MD, PhD, then an assistant professor of medicine at UCSF, now at Emory University, Atlanta, Georgia. UCSF has recently licensed this technology to a company, Iguazu Biosciences Corp., established by Andino and other scientists to carry out human trials of an HIV vaccine using this approach. Like the Sabin poliovirus vaccine used 40 years ago, the new vaccine will be administered orally, an important advantage over most other proposed AIDS vaccines.

A report on the SIV vaccine success appears in the August 2, 2001, issue of the Journal of Virology. Andino is senior author on the paper.