Experimental HIV vaccine targets virus envelope protein

by Sorina Buzatu
Experimental HIV vaccine targets virus envelope protein

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 responsible for the fusion of the HIV virus with human cells. By integrating the gp41 protein into the vaccine, researchers are attempting to trigger the production of antibodies that would block the entrance of HIV into human cells.

"We have used an innovative approach, combining protein engineering, specific vaccine formulation, and a combination of routes of administration, [nasal] and intramuscular," says Nicolas Mouz, chief scientific officer at PX'Therapeutics, one of the project partners. The company is also providing protein engineering research and manufacturing. It is located in Grenoble, France.

There have been many since the discovery of the virus in the early 1980s, seeking both a cure for infected people and a preventative therapy to stop the contagion. "This gp41 protein from the virus envelope is not an absolute novelty in the long history of anti HIV ," says Alexandru Rafila, Chairman of the Romanian Society for Microbiology in Bucharest. "But it is a meaningful approach in protein design that could be given as a vaccine so that it triggers an ."

The trouble is that the virus targets not only the lymphocyte cells, which include T cells—a key component of the body's immune system helping to fight diseases—but also other immune system cells. The latter are not exclusively infected through the gp41 protein but also through other mechanisms. "An efficient vaccine should hamper the infection of any other cells," Rafila says.

Other experts concur that the diversity of HIV and its enormous capacity to mutate are major challenges for vaccine development. "The idea basically is that a vaccine should induce antibodies T cells immune response, that would neutralise HIV in all of its forms," says Ulrich Fruth, vaccine development and evaluation team leader at the World Health Organisation, in Geneva, Switzerland.

Even though Fruth considers the project strategy a viable approach, chances of success for this vaccine are difficult to predict. "We just don't know," he says. "The only thing we know is that we have more experience on human trials. The animal models used so far were not very predictive. We need human clinical trials in order to decide which vaccine to take forward." The vaccine is in its first stage of clinical safety studies, which demonstrated a relatively weak effect. It is still too early to draw conclusions.

In addition, Fruth points to a minor limitation of this vaccine, namely that it focuses on the induction of antibodies. He says, "We think that for a successful protection we may need [to target] both: antibodies and T cells. The role that I would see for such a vaccine would probably be in combination with the components that induce T cell immune response. So, [what may prove useful is to test] a combination [and] not a standalone one."

Related Stories

Study explores barriers to HIV vaccine response

date Sep 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 ...

Researchers report cats may be the key to human HIV vaccine

date Oct 02, 2013

(Medical Xpress)—Blood from HIV-infected human subjects shows an immune response against a cat AIDS virus protein, a surprise finding that could help scientists find a way to develop a human AIDS vaccine, report University ...

New artificial protein mimics a part of the HIV outer coat

date Oct 22, 2013

A team of scientists at Duke Medicine and Memorial Sloan-Kettering Cancer Center has created an artificial protein coupled with a sugar molecule that mimics a key site on the outer coat of HIV where antibodies can bind to ...

HIV vaccines elicit immune response in infants

date Oct 08, 2013

A new analysis of two HIV vaccine trials that involved pediatric patients shows that the investigational vaccines stimulated a critical immune response in infants born to HIV-infected mothers, researchers at Duke Medicine ...

HIV/AIDS vaccines: Defining what works

date Jul 18, 2013

Designing an effective HIV/AIDS vaccine is something of a paradox: a good vaccine would be safe and look enough like HIV to kick-start the immune system into neutralizing the virus – but the problem is that this is exactly ...

Recommended for you

Indiana HIV outbreak, hepatitis C epidemic sparks US alert

date 11 hours ago

Federal health officials helping to contain an HIV outbreak in Indiana state issued an alert to health departments across the U.S. on Friday, urging them to take steps to identify and track HIV and hepatitis C cases in an ...

Why are HIV survival rates lower in the Deep South than the rest of the US?

date Apr 22, 2015

The Deep South region has become the epicenter of the US HIV epidemic. Despite having only 28% of the total US population, nine states in the Deep South account for nearly 40% of national HIV diagnoses. This region has the highest HIV diagnosis rates and the highest number of people living with HIV of any ...

A bad buzz: Men with HIV need fewer drinks to feel effects

date Apr 20, 2015

Researchers at Yale and the VA Pittsburgh Healthcare System compared the number of drinks that men with HIV infection, versus those without it, needed to get a buzz. They found that HIV-infected men were more sensitive to ...

Research informs HIV treatment policy for inmates

date Apr 16, 2015

A national, five-year study of care for inmates with HIV brought strangers together, produced policy change in the Delaware Department of Corrections and documented the importance of good communication and ...

User comments

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.