Vaccine stimulating production of HIV-1 virus antibodies may be developed soon

Researchers have found in a new study that process of defending the body from autoimmune disease seems to avert it from producing antibodies that can neutralize the HIV-1 virus, a discovery that may help to develop a vaccine that fuels production of these antibodies.

The team tried to understand better how the body`s own immune system may be getting in the way of neutralizing the HIV-1 virus.

The group understood that some patients infected with HIV-1 developed what are known as `broadly neutralizing antibodies, ` or bnAbs, that can defend against a wide range of HIV-1 strains by identifying a protein on the surface of the virus called Env.

But the infected patients take many years to develop these antibodies.

Because of shared features found in several HIV-1 bnAbs, scientists suspected the inability or delayed ability to make such protective antibodies against HIV was because of the immune system overpowering production of the antibodies to stop the body from creating self-reactive antibodies that could result in autoimmune diseases like systemic lupus erythematosus.

Simultaneously, patients with lupus showed slower rates of HIV-1 infection. Scientists are of the opinion that`s because these autoimmune patients produce self-reactive antibodies that identify and neutralize HIV-1.

The process by which the body prevents the creation of antibodies that can result in autoimmune disease is known as immunological tolerance. Torres sought to break that tolerance and arouse the production of antibodies that could neutralize HIV-1.

"We wanted to see if people could make a protective response to HIV-1 without the normal restraint imposed by the immune system to prevent autoimmunity," shared Raul M. Torres, PhD, professor of immunology and microbiology at the University of Colorado School of Medicine.

The researchers first experimented on mice with genetic defects that caused lupus-like symptoms.

They discovered that several of them produced antibodies that could neutralize HIV-1 after being administered alum, a chemical that kindles antibody secretion and is frequently in vaccinations.

They gave normal mice a drug that damages immunological tolerance and found that they started to produce antibodies capable of neutralizing HIV-1. The production of these antibodies was spurred by alum injections.

If HIV-1 protein Env was also administered to the mice, they produced potent broadly neutralizing antibodies capable of neutralizing a range of HIV-1 strains. in every case, the production of these HIV-neutralizing antibodies related to the levels of a self-reactive antibody that identifies a chromosomal protein called Histone H2A.

The researchers endorsed these antibodies could neutralize HIV-1. Torres explained, "We think this may reflect an example of molecular mimicry where the virus has evolved to mimic or look like a self-protein."

Torres implied that the trouble in developing a vaccine against HIV-1 may be because of the capability of the virus to disguise itself as a normal part of the body.

"But breaching peripheral immunological tolerance permits the production of cross-reactive antibodies able to neutralize HIV-1," shared Torres.

Since the experiment was conducted on animal’s scientists must still establish its relevance for HIV-1 immunity in humans.

"The primary consideration will be determining whether immunological tolerance can be temporarily relaxed without leading to detrimental autoimmune manifestations and as a means to possibly elicit HIV-1 bnAbs with vaccination," he concluded.

The study was published in The Journal of Experimental Medicine.