In a significant progress towards the development of a vaccine against HIV, scientists have devised a new approach to help the immune system actively fight the virus in the body. Australian researchers have showed that a combined approach—using a common cold virus to introduce a vaccine into the body, as well as an injection of a DNA-based vaccine—may help protect against HIV in the gut and bodily cavities.
“With sexual activity being one of the primary methods of HIV transmission, it is necessary to try to protect those parts of the body that are most likely to encounter the virus first,” says Branka Grubor-Bauk of the University of Adelaide in Australia.
The laboratory studies have been conducted in mice so far. “In mice, we delivered a rhinovirus (or common cold virus) inside the nose, and this virus had been altered to include HIV proteins,” Grubor-Bauk says. “At the same time, the mice also received an injection into the skin containing a DNA-based vaccine. This approach resulted in very specific responses in the immune system,” she adds.
This vaccine approach encompasses two different arms of the immune system: white blood cells that attack the HIV virus, and specific antibodies that recognize and shut down HIV-positive cells, she says. “There is an element of HIV known as Tat that helps the virus to replicate quite rapidly,” explains Eric Gowans, professor at the University of Adelaide.
The antibodies inhibit the Tat effect, preventing HIV from replicating itself, Gowans says, adding, “Overall, we found that infection was considerably reduced in the mice we studied. The study will appear in the journal Scientific Reports