New Antibody Discovery for Long Term HIV Control
A potent anti-HIV 1 neutralizing antibody- 3BNC117 can resurrect the current HIV treatment options through passive immunization approach, to establish long term control of HIV.
HIV continues to be the world’s most dreaded health challenge affecting millions of people around the world. In 2015, about 15.8 million cases of HIV were reported.
Antiretroviral therapy (ART), also known as combination therapy where the patients are treated with 2-3 drugs to slow down the viral replication is the treatment that is being given so far to combat AIDS. These antiretroviral drugs can reduce the viral count in blood stream but cannot act as a cure for this syndrome.
As HIV multiplies it also undergoes a number of mutations. These mutant viruses can keep replicating despite treatment with drugs. This in turn will inactivate the ART. If one misses a few doses the level of virus in blood is bound to increase. Side effects such as gastrointestinal problems, kidney problems and osteoporosis were also reported in patients undergoing currently available therapy.
The Shining Strategy
Scientists from Rockefeller University collaborated with researchers of University of Cologne and elicited the 3BNC117-mediated immunotherapy that could lower the viral load in patient’s blood to a significant amount by building up the host humoral immunity to HIV 1. A single infusion of 3BNC117 to HIV 1 infected individuals showed substantial improvement in neutralizing responses to heterologous tier 2 viruses in almost all volunteers. The detailed observations on the effect of the 3BNC117 in patient’s immune system was published in May 5, edition of Science.
The Antibody of choice
3BNC117, an antibody isolated by Johannes F. Scheid is the antibody used in the research. This antibody has the ability to work against a broad spectrum of HIV strains neutralizing more than 80% of HIV strains identified so far. They prevent the viruses from attacking and destroying the CD4 cells whose destruction is an important cause for progression of HIV. This led to a hypothesis that infusion of these antibodies would obliterate HIV in a patient’s body.
15 volunteers with high viral load in blood not receiving ART and 12 others on ART were chosen for the trial. One dose of 3BNC117 was administered and the patients were monitored closely for six months.
14 patients with high viral load in blood showed significant progress. Analyzing their immune system, researchers found that new antibodies acting against different HIV strains are being produced.
Schoofs, a member of Laboratory of Molecular Immunology stated,” This study provides evidence that a single dose of an antibody stimulates patient’s immune response, enabling them to make new or better antibodies against the virus. It usually takes several years for the body to begin to make good antibodies against HIV. So there might be an even better effect later on, especially if patients are given more than one dose of 3BNC117“.
A Parallel study!
In parallel, a study was conducted to identify the advantage of 3BNC117 over ART by using a mathematical model of HIV dynamics. This study has shown the possibility that another component might be involved in bringing about the efficiency of antibody. The finding that mere neutralization of existing virus alone is not responsible for rapid decline in viral load has led to this possibility.
A mouse model study by a team of researchers under Ching-Lan-Lu found that 3BNC117 can influence other immune cells of animals to rapidly obliterate HIV infected cells.
Ching-Lan-Lu says,”This shows that the antibody not only can exert pressure on the virus, but also can shorten the survival of infected cells. Our results explain why post-exposure prophylaxis–short-term treatment after exposure to HIV to reduce infection–with antibodies is more effective than ART in our mouse models”.
Research is in progress to make 3BNC117 treatment available to the patients under ART as an alternative. Efforts are being made to develop a stronger antiviral effect by using 3BNC117 with other antibodies that target HIV.
3BNC117-mediated immunotherapy would drastically alter the approach of HIV treatment. However, a single dosage of antibody treatment is highly expensive. Considering, HIV to be widespread only in developing countries, there is an urgent need for initiatives, to fasten the development of the antibody treatment, making it available and affordable to the masses as soon as it gets approved.
Featured image credit: Disease, Infection, Hiv Cells Attacking Organism © picture-waterfall (Stock Photo ID: 112935401)