News / Health

Scientists Make Strides Toward AIDS Vaccine

Scientists have discovered why some people who are infected with HIV progress to AIDS very slowly, if ever.  They possess a gene that produces a potent immune response that keeps the infection at bay.  Researchers say their finding might someday lead to an AIDS vaccine.

About one in 200 people infected with HIV are so-called elite controllers, HIV-positive people who do not progress to AIDS, even without drugs, after many decades of being infected with the virus that causes AIDS.

Researchers have identified a protective mechanism produced by a gene called HLA-B57 that is found in elite controllers.  

The gene produces large numbers of immune system T cells, a type of infection-fighting white blood cell,  that latch on to cells that have been taken over by HIV, including mutated copies of the virus, and contain the damage caused by the disease.

Once activated, the programmed T cells also scour the rest of the body for other HIV-infected cells and kill them.

In previous research, scientists identified another gene in elite controllers called HLA-B27.  The presence of either gene seems to stave off AIDS in people infected with HIV.

Chemical engineer Arup Chakraborty, at Massachusetts Institute of Technology, developed a computer model of T cell development though the thymus, an organ behind the breast bone that conditions immune cells to recognize infections.

"Our findings suggest that the T cells that pass and come out of the thymus in people with HLA-B57 or HLA-B27 tend to be able to bind more strongly to strains of HIV that are infecting strains as well as mutants that emerge.  So their T cells repertoires are somewhat different," said Chakraborty.

A study of nearly 2,000 HIV infected patients - with and without the HLA genes - confirmed that those who lacked the genes did not have the immune system brake and they progressed to AIDS.

Scientists discovered the effect of elite controllers in HIV-positive patients during the late-1990s.  Since then, they have been trying to identify the immune system component that shields elite controllers from AIDS, so they can develop a vaccine.

Leading efforts to understand this rare group of HIV-infected people is Bruce Walker, an AIDS researcher at Harvard University and Massachusetts General Hospital, and co-author of the study.

Dr. Walker says the problem with developing a vaccine is that HIV is like a moving target, mutating rapidly after someone is infected and causing inevitable decline.

But Dr. Walker says the fact that the HLA-B57 and HLA-B27 genes control the virus, even as it mutates in some HIV-positive patients, might make an AIDS vaccine a reality.

"I think the fact that there are people out there that can be infected with HIV and successfully control it for decades tells me that this is a virus that we can get the upper hand with.  And I think this is a solvable problem," he said.

However Dr. Walker cautions that an AIDS vaccine is at least a decade away.

An article describing the genetic mechanism that slows progression of the AIDS virus is published this week in the journal Nature.

You May Like

Video Claims to Show Shia Forces in Iraq Executing Sunni Boy

While not yet independently confirmed, brutal killing already has gotten attention of Islamic State followers on social media More

After Six Years, Little Change for Niger Delta's Former Militants

Nigerians who laid down arms in exchange for government amnesty subsidies fear program may end with upcoming presidential elections More

Vietnam Pushes for More Educated Drivers to Curb Road Deaths

Transportation officials hope that making a greater effort to get drivers to learn the rules of the road will reduce fatal crashes More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
NASA Spacecraft Approaches a Dwarf Planeti
X
George Putic
March 04, 2015 8:51 PM
NASA’s Dawn spacecraft will make history on Friday, March 6, when it becomes the first man-made object to orbit a dwarf planet named Ceres. It is located in the asteroid belt between Mars and Jupiter, almost 500 million kilometers from Earth. Among other objectives, Dawn will try to examine two mysterious bright white spots detected on the planet’s surface. VOA’s George Putic has more.
Video

Video NASA Spacecraft Approaches a Dwarf Planet

NASA’s Dawn spacecraft will make history on Friday, March 6, when it becomes the first man-made object to orbit a dwarf planet named Ceres. It is located in the asteroid belt between Mars and Jupiter, almost 500 million kilometers from Earth. Among other objectives, Dawn will try to examine two mysterious bright white spots detected on the planet’s surface. VOA’s George Putic has more.
Video

Video Young Muslims Radicalized Online

Young Muslims are being radicalized ‘in their bedrooms’ through direct contact with Islamic State or ISIL fighters via the Internet, according to terror experts. There are growing concerns that authorities and Internet providers are not doing enough to counter online extremism - which analysts say is spread by a prolific network of online supporters around the world. Henry Ridgwell reports from London.
Video

Video African Americans Recall 1960's Fight For Voting Rights

U.S. President Barack Obama and thousands of people will gather in the small southern U.S. city of Selma, Alabama, Saturday, March 7th to commemorate the 50th anniversary of a historic voting rights march that became known as “Bloody Sunday." VOA’s Chris Simkins traveled to Alabama and introduces us to some of the foot soldiers of the voting rights struggles of the 1960’s.
Video

Video Positive Messaging Transforms Ethiopia's Image

Ethiopia was once known for famine and droughts. Now, headlines more often point to its fast-growing economy and its emergence as a regional peacemaker. How has Addis Ababa changed the narrative? VOA's Marthe van der Wolf reports.
Video

Video Cyber War Rages Between Iran, US

A newly published report indicates Iran and the United States have increased their cyber attacks on each other, even as their top diplomats are working toward an agreement to guarantee Iran does not develop a nuclear weapon and to free Iran from international sanctions. The development is part of a growing global trend. VOA’s Al Pessin reports from London.
Video

Video Answers Elude Families of MH370 Passengers

For the families on board Malaysia Airlines flight MH370, an airline official’s statement nearly one year ago that the plane had lost contact with air traffic control at 2:40 AM is the only thing that remains confirmed. William Ide reports.
Video

Video Land Disputes Arise Amid Uganda Oil Boom

Ugandan police say there has been a sharp increase in land disputes, with 10 new cases being reported each day. The claims come amid an oil boom as investors appear to be cashing in by selling parcels of land to multiple buyers. Meanwhile, the people who have been living on the land for decades are chased away, sometimes with a heavy hand. VOA's Serginho Roosblad reports.
Video

Video In Russia, Many Doubt Opposition Leader's Killer Will Be Found

The funeral has been held in Moscow for Boris Nemtsov, the opposition leader who was assassinated late Friday just meters from the Kremlin. Nemtsov joins a growing list of outspoken critics of Russia under the leadership of President Vladimir Putin who are believed to have been murdered for their work. VOA’s Daniel Schearf reports from Moscow.
Video

Video Simulated Astronauts Get Taste of Mars, in Hawaii

For generations, people have dreamed of traveling to Mars to explore Earth's closest planetary neighbor. VOA's Mike O'Sullivan reports that while space agencies like NASA are planning manned missions to the planet, some volunteers in Hawaii are learning how humans will cope with months in isolation on a Mars base.
Video

Video Destruction of Iraq Artifacts Shocks Archaeologists

The city of Mosul was once one of the most culturally rich and religiously diverse cities in Iraq. That tradition is under attack by members of the Islamic State who have made Mosul their capital city. The Mosul Museum is the latest target of the group’s campaign of terror and destruction, and is of grave concern to archaeologists around the world. VOA’s Kane Farabaugh reports.
Video

Video Smartphones May Help in Diagnosing HIV

Diagnosing infections such as HIV requires expensive clinical tests, making the procedure too costly for many poor patients or those living in remote areas. But a new technology called lab-on-a-chip may make the tests more accessible to many. VOA’s George Putic reports.
Video

Video Afghan Refugees Complain of Harassment in Pakistan

Afghan officials have expressed concern over reports of a crackdown on Afghan refugees in Pakistan following the Peshawar school attack in December. Reports of mass arrests and police harassment coupled with fear of an uncertain future are making life difficult for a population that fled its homeland to escape war. VOA’s Ayesha Tanzeem reports from Islamabad.

All About America

Circumventing Censorship

An Internet Primer for Healthy Web Habits

As surveillance and censoring technologies advance, so, too, do new tools for your computer or mobile device that help protect your privacy and break through Internet censorship.
More