How FIV May Ultimately Set the Stage for an HIV Vaccine
New research is promising
Researchers recently discovered that a protein from the virus that causes AIDS in cats triggers an immune response in blood from HIV-infected people. Experts are hopeful that cats may hold a key to developing an HIV vaccine for people, according to a new study.
The findings were reported in the Journal of Virology (October 2013), and suggest that further research with FIV could eventually lead to an HIV vaccine for people, the University of Florida and University of California, San Francisco investigators said. The virus that causes AIDS in people is called the human immunodeficiency virus, while the one that affects cats is called the feline immunodeficiency virus (FIV).
“One major reason why there has been no successful HIV vaccine to date is that we do not know which parts of HIV to combine to produce the most effective vaccine,” explained Janet Yamamoto, a professor of retroviral immunology at the UF College of Veterinary Medicine. In previous studies, scientists have combined various whole HIV proteins as vaccine ingredients — but unfortunately none worked well enough to be used as a commercial vaccine.
“Surprisingly, we have found that certain peptides of the feline AIDS virus can work exceptionally well at producing human T-cells that fight against HIV,” said Yamamoto. T-cells are immune system cells that attack cells infected with viruses.
The FIV protein that triggered the human T-cell response is present in multiple HIV-like viruses in different animal species. By studying FIV, the researchers believe that it may be possible to identify regions of HIV that might prove useful targets for a vaccine.
Additionally, the researchers want to emphasize that different viruses affect people and cats. “We want to stress that our findings do not mean that the feline AIDS virus infects humans, but rather that the cat virus resembles the human virus sufficiently so that this cross-reaction can be observed,” study co-author Dr. Jay Levy, a professor of medicine at UCSF.
According to Yamamoto, there would be no health risk associated with an HIV vaccine if it were developed from the results because it would be protein-based; in other words, there would be no viral genome present in the vaccine to lead to infections.
She estimates that a vaccine is likely to be available for humans within the next seven to eight years.