Research may be beating HIV, but a vaccine remains distant

July 11, 2014 by John Mcluskey, The Conversation
This would be the ideal way to fight HIV. Credit: europedistrict, CC BY

Three decades since the onset of the infection in a global population, HIV care and treatment is looking very different. Given the difficulties involved, it is remarkable that having developed good treatments, the global community is racing towards finding a vaccine cure.

The first clinical observation of AIDS was recorded in the US in 1981. The focus then was to identify what caused the new disease and to help people to a dignified death. Once HIV was identified, understanding the behaviour of the virus became vital.

Soon antiretroviral therapies were developed that attempted to disrupt the replication of the virus in the body. In the late 1990s, a combination of these therapies showed better results and had a huge impact on the future of HIV-infected individuals. In the UK the healthcare discourse changed from the person dying from AIDS to the person living with HIV. Today, those individuals diagnosed with HIV infection have a similar life expectancy to those without.

Now research is gathering pace to search for a cure. A recent advert from Cancer Research UK claims "research is beating HIV". However, it is not that simple.

There have been claims of a cure for a few individuals: the now famous Timothy Ray Brown, known as the "Berlin patient", became clear of his HIV while receiving for his leukaemia. In Mississippi in the US, a baby was treated with antiretroviral therapies for the first 18 months of her life and appears to be infection-free. The "Visconti group" consisting of 14 patients with HIV who have had their stopped with no sign of further infection.

However, transplantation would not be the most appropriate way forward as the procedure carries risks in itself. Also two men undergoing treatment for lymphoma in Boston, US showed a return to HIV infection some months after their transplants. Seeking a cure is still needed.

The development of a vaccine for HIV is complex and this is what leads to its elusiveness. The purpose of a vaccine is to provide a protective immune response to a particular microorganism. The body's immune system produces antibodies that purge the microorganism with weapons tailored to specifically attack it.

But this is where the difficulties begin: HIV undergoes many mutations, as do most viruses and, therefore, we are not dealing with just one-size-fits-all weapon to fight a virus. The virus also has the ability to evolve resistance to immune control. Our understanding of HIV's adaptive evolution must improve if vaccination development is going to be effective.

In creating an appropriate approach to vaccine development the response of the immune system to the virus is important as we want to encourage the development of antibodies to the proteins within the virus. According to a new review published in the journal Science, two approaches to elicit antibody protection in HIV are being pursued: a vaccine that is potent and produces broadly reactive neutralising antibodies (bnAbs) and vaccines that induce "conventional antibodies".

Broadly reactive neutralising antibodies (bnAbs) are considered important as they are more likely to cope with mutations of viruses. When developed they ought to be potent and induce high levels of protection. But there are complexities with their structure and it may take months to years in order to evolve a response.

On the other hand, conventional antibodies are less potent but they are produced by the majority of infected individuals and are the only antibodies that have been seen in to date. Unlike bnAbs, conventional antibodies take only weeks to months to evolve a response.

While bnAbs are probably the desired approach to , vaccines that support conventional antibodies should not be ignored as they have shown some success in clinical trials. It is not the time to put all our eggs in one basket and research into the development of a should concentrate on both approaches.

Explore further: A cure for HIV is a 'major scientific priority,' says researcher

Related Stories

A cure for HIV is a 'major scientific priority,' says researcher

June 24, 2014
Huge advancements have taken place in HIV treatment and prevention over the past 10 years, but there is still no cure or vaccine.

Scientists create new tool for identifying powerful HIV antibodies

May 9, 2013
A team of NIH scientists has developed a new tool to identify broadly neutralizing antibodies (bNAbs) capable of preventing infection by the majority of HIV strains found around the globe, an advance that could help speed ...

Past HIV vaccine trials reveal new path to success

March 19, 2014
A multi-national research team led by Duke Medicine scientists has identified a subclass of antibodies associated with an effective immune response to an HIV vaccine.

Durable end to AIDS will require HIV vaccine development

February 5, 2014
Broader global access to lifesaving antiretroviral therapies and wider implementation of proven HIV prevention strategies could potentially control and perhaps end the HIV/AIDS pandemic. However, a safe and at least moderately ...

Study of antibody evolution charts course toward HIV vaccine

March 2, 2014
In an advance for HIV vaccine research, a scientific team has discovered how the immune system makes a powerful antibody that blocks HIV infection of cells by targeting a site on the virus called V1V2. Many researchers believe ...

Unique individual demonstrates desired immune response to HIV virus

March 10, 2014
One person's unique ability to fight HIV has provided key insights into an immune response that researchers now hope to trigger with a vaccine, according to findings reported by a team that includes Duke Medicine scientists.

Recommended for you

War in Ukraine has escalated HIV spread in the country: study

January 15, 2018
Conflict in Ukraine has increased the risk of HIV outbreaks throughout the country as displaced HIV-infected people move from war-affected regions to areas with higher risk of transmission, according to analysis by scientists.

Researchers offer new model for uncovering true HIV mortality rates in Zambia

January 12, 2018
A new study that seeks to better ascertain HIV mortality rates in Zambia could provide a model for improved national and regional surveillance approaches, and ultimately, more effective HIV treatment strategies.

New drug capsule may allow weekly HIV treatment

January 9, 2018
Researchers at MIT and Brigham and Women's Hospital have developed a capsule that can deliver a week's worth of HIV drugs in a single dose. This advance could make it much easier for patients to adhere to the strict schedule ...

New long-acting, less-toxic HIV drug suppresses virus in humanized mice

January 8, 2018
A team of Yale researchers tested a new chemical compound that suppresses HIV, protects immune cells, and remains effective for weeks with a single dose. In animal experiments, the compound proved to be a promising new candidate ...

Usage remains low for pill that can prevent HIV infection

January 8, 2018
From gritty neighborhoods in New York and Los Angeles to clinics in Kenya and Brazil, health workers are trying to popularize a pill that has proven highly effective in preventing HIV but which—in their view—remains woefully ...

Researchers find clues to AIDS resistance in sooty mangabey genome

January 3, 2018
Peaceful co-existence, rather than war: that's how sooty mangabeys, a monkey species found in West Africa, handle infection by SIV, a relative of HIV, and avoid developing AIDS-like disease.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.