Can you believe that it was only a little over 30 years ago that the first case of HIV appeared in the United States? After its arrival, no one could have predicted what destruction it could bring with it. Over 675,000 people have died from the progression of HIV into AIDS since the 1980’s, however; medical breakthroughs are on the rise to prevent HIV positive individuals from progressing into AIDS rapidly and reducing their viral loads to such low levels that it is almost impossible to transmit the disease to another individual. In fact, those who are HIV positive life span is almost nearly the same to that of unaffected individual.
Although the HIV epidemic has significantly decreased, Americans are still reaching the AIDS stage which continues to motivate scientists to develop a better vaccine for those at risk of HIV. When HIV was first discovered, the hope was to develop a one time vaccine that would combat this deadly disease. Currently, the Uhambo vaccine requires a five step process which takes up to a year complete and people may need to repeat vaccination every few years which is not only time consuming but also can become expensive. A one shot vaccine would allow an easily manufactured, effective vaccine for global HIV vaccination drives. However, the optimism for a “one and done” vaccine slowly faded with realization that the vaccine has very powerful virulence factors that allow the virus to integrate its DNA into the host cell and cause very individualized symptoms. However, new studies have renewed hope in a single-shot vaccine!
Currently, HIV is being combated with multi-shot injection strategies with the goal to slowly allow the immune system to find and destroy the virus. However, researchers from Scripps Reasearch Institute in La Jolla, California have developed a single usage HIV vaccine that may alter the approach of fighting HIV. This vaccine, SOSIP BG505 env trimmer, triggers the body to create bNAbs, which are antibodies that are normally seen in HIV patients that have been infected with the disease for many years. In fact, this unique study is the first time that scientists have been able to induce this type of reaction in a mammal other than cows which proves optimistic but also a barrier as it may not respond in humans.
The vaccine works by a viral like particle (VLP) with the shape of the trimer which is comparable to that of a fidget spinner that an important protein gp120 from the virus needs to also adopt in order to infect host cells. This makes it difficult for the virus to change the shape of the protein without losing function because the trimer exposes parts of the protein that are normally conserved. The result is that the virus is neutralized and can’t mutate certain responses.
The hope for this vaccine is that it will create a “complete response” to HIV in the chance that HIV exposure does happen. Researchers hope that it will not only be able to turn away the virus but also contain it in the chance that infection does occur. The study included 78 monkeys and compared antibody response of those with the highest and lowest immune reactions.
The results showed that the vaccine was only somewhat effective in those who produced a low immunity response with two of the monkey contracting HIV after 6 weekly doses of the vaccine. However, only one monkey in the high response group contracted HIV in the first round, one in the second round, and two in the third round, with the rest of the monkeys making it successfully through the trials without contracting the infection.
Although this has not yet been tested on humans, researchers are optimistic about the concept study and will be looking at the safety and efficacy of the new vaccine in the upcoming months in hopes that a one-shot vaccine may one day be effective.
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