Research on the protein gp41 could help towards designing future vaccinations against HIV

March 17, 2014, University of Granada

Researchers from the University of Granada have discovered, for the first time, an allosteric interaction (that is, a regulation mechanism whereby enzymes can be activated or de-activated) between this protein, which forms part of the sheath of the Human Immunodeficiency Virus (HIV) and the antibody 2F5 (FAB), a potent virus neutralizer. This important scientific breakthrough could help specialists to understand the mechanisms behind generating immune responses and help towards the design of future vaccines against the HIV virus.

Although modern antiretroviral therapies have improved enormously the treatment of AIDS, their high cost means that they do not reach the more disadvantaged communities. Furthermore, these treatments do not completely eliminate HIV, since it remains dormant, with the danger of resurging if the patient stops the medication.

But, after several decades of research, there is still no effective vaccine. The main reason is that HIV manages to "trick" our immune system, hiding in it via a wide variability of its proteins, or confusing it through immune responses that turn out to be ineffective in preventing the infection.

The study carried out by University of Granada scientists, and recently published in The Journal of Biological Chemistry, falls within the framework of a line of research into new therapeutical immunization techniques that attempt to induce neutralizing antibodies similar to those found, in low levels, in HIV-infected patients. One of these antibodies, known as 2F5 FAB, is being studied intensively, given its strong neutralizing potential.

2F5 recognises an epitope from protein gp41, which forms part of the HIV sheath. Protein gp41 rarely varies, since its activity is essential for invading T lymphocytes, due to the virus, since it promotes the fusión between the viral and cellular mibranes. Antibody 2F5 is able to block this fusión by linking onto gp41, thus protecting cells from HIV infection.

The main author of this research, University of Granada Physical Chemistry lecturer,Francisco Conejero Lara, points out that "one of the main aims of current research into HIV vaccines consists of inducing neutralizing antibodies similar to 2F5 via immunization using an appropriate vaccine. To do this, studies into how 2F5 recognises its epitope in gp41 are fundamental, since they can provide the way to designing effective vaccines".

To this end, a wide-spreading European collaboration consortium, called "Euroneut-41", financed by the 7th EU Framework Programme, is attempting to design and develop vaccines to combat HIV. The consortium is formed by 16 European instituions, including companies, universities, research institutes and hospitals. Their ultimate aim is to develop posible vaccines against HIV.

The research group "Biophysics and Molecular Biology FQM-171", belonging to the University of Granada's Department of Physical Chemistry and led by the lecturers Pedro Luis Mateo and Francisco Conejero Lara, is the only Spanish group in this consortium and is taking part in the molecular design and the biophysical characterization of various vaccine candidates base don protein gp41.

During this study, the University of Granada researchers, via isothermic titration calorimetry, the interaction between antibody 2F5 and two different fragments of protein gp41 that contain its epitope. The results have helped to pinpoint how the different regions of the gp41 epitope contribute toward the energy of the union with the antibody.

Explore further: Two new HIV vaccine candidates: Q&A with Nicolas Mouz

More information: Thermodynamic analysis of the binding of 2F5 Fab and IgG to its gp41 epitope reveals a strong influence of the immunoglobulin Fc region on the affinity: … C113.524439.abstract

Related Stories

Two new HIV vaccine candidates: Q&A with Nicolas Mouz

November 27, 2013
European researchers have designed two new vaccine candidates to fight the HIV virus. These have been developed within the EU-funded project EURONEUT 41. They work by targeting the mechanism of HIV entry into the body via ...

Experimental HIV vaccine targets virus envelope protein

November 27, 2013
AIDS research has investigated many strategies to tackle the HIV virus. Now, a new type of vaccine developed within the EU-funded project EuroNeut-41, targets an HIV envelope protein called the gp41. The protein is directly ...

Neutralizing HIV function

November 3, 2011
(Medical Xpress) -- Northeastern researchers have played a key role in studying how antibodies that neutralize HIV function are structured, a further step in ongoing global efforts by scientists to develop a vaccine for the ...

Study explores barriers to HIV vaccine response

September 20, 2013
Researchers at The Scripps Research Institute (TSRI) discovered that an antibody that binds and neutralizes HIV likely also targets the body's own "self" proteins. This finding could complicate the development of HIV vaccines ...

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 ...

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.