Could cows be the clue that leads to an HIV vaccine?

There was crashing news on BBC recently: they reported that US scientists were shocked by the amazing ability of cows to tackle HIV. So American scientists say that it may result in synthesizing HIV vaccine.

For the time being there is no effective vaccine for HIV because the virus mutates so fast and easily. Researchers all over the globe do their very best to develop a vaccine which will provoke an immune response.

The report is based on research published in July 2017 in Nature describing cows that were immunized against HIV using the immunogen called BG505 SOSIP which mimics the outside of the HIV virus and stimulates an immune response. Researchers aimed to find out if the immunogens were “broad” (could neutralize many different viral strains) and potent by determining how long it took for the immune response to occur: the faster the response the more potent a vaccine tends to be.

Cows were chosen as unlike most other animals, they have longer amino acid chains. Previous research demonstrated that a small number of people with HIV who developed a level of natural immunity to HIV also have similarly long amino acid chains.

All cows developed immune cells to HIV within 35–50 days following two injections. One cow showed an immune response that could neutralize only 1 of 5 HIV strains (20% of HIV strains tested in the lab) in 42 days and another neutralized 96% of HIV strains in 381 days. What’s more, while analyzing the proteins synthesized as a part of the immune response, the researchers found out that one, in particular, binds to a key HIV site that the virus uses to infect cells.

This early stage research on cows shows that they had a broad and quick immune response to HIV infection when given a specific vaccine. As always with animal studies, it is important to keep in mind that what works in cows might not work in the same way in humans. Many drug studies that appear promising at first, fall at the first hurdle once humans are involved.