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

Arab League Delays Forming Joint Force

Delay grows out of one of original obstacles facing pan-Arab force, analysts say: 'They may agree on the principle, but they continue to argue about how to implement the project' More

Pakistan Demands Afghanistan Protect Its Kabul Mission, Staff

Officials in Islamabad say Afghan agents are harassing Pakistani embassy personnel, particularly those living outside of mission’s compound More

US Survey: Trump Lead Grows in Republican Presidential Contest

Quinnipiac University poll shows brash billionaire real estate mogul with 28 percent support among Republican voters 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.
Colombians Flee Venezuela as Border Crisis Escalatesi
X
August 27, 2015 2:08 AM
Hundreds of Colombians have fled Venezuela since last week, amid an escalating border crisis between the two countries. Last week, Venezuelan President Nicolas Maduro ordered the closure of a key border crossing after smugglers injured three Venezuelan soldiers and a civilian. The president also ordered the deportation of Colombians who are in Venezuela illegally. Zlatica Hoke reports.
Video

Video Colombians Flee Venezuela as Border Crisis Escalates

Hundreds of Colombians have fled Venezuela since last week, amid an escalating border crisis between the two countries. Last week, Venezuelan President Nicolas Maduro ordered the closure of a key border crossing after smugglers injured three Venezuelan soldiers and a civilian. The president also ordered the deportation of Colombians who are in Venezuela illegally. Zlatica Hoke reports.
Video

Video Is China's Economic Data Accurate?

Some investors say China's wild stock market gyrations have been made worse by worries about the reliability of that nation's economic data. And some critics say the reports can mislead investors by painting an unrealistically-strong picture of the economy. A key China scholar says Beijing is not fudging ((manipulating)) the numbers, but that the economy is evolving quickly from smoke-stack industries to services, and the ways of tracking new economic activity are falling behind the change. V
Video

Video Next to Iran, Climate at Forefront of Obama Agenda

President Barack Obama this week announced new initiatives aimed at making it easier for Americans to access renewable energy sources such as solar and wind. Obama is not slowing down when it comes to pushing through climate change measures, an issue he says is the greatest threat to the country’s national security. VOA correspondent Aru Pande has more from the White House.
Video

Video Shipping Containers Provide Experimental Housing

Housing prices around the San Francisco Bay area are out of reach for many people, so some young entrepreneurs, artists and tech industry workers are creating their own houses using converted shipping containers. But as VOA's Mike O’Sullivan reports from Oakland, the effort requires ingenuity and dealing with restrictive local laws.
Video

Video Arctic Draws International Competition for Oil

A new geopolitical “Great Game” is underway in earth’s northernmost region, the Arctic, where Russia has claimed a large area for resource development and President Barack Obama recently approved Shell Oil Company’s test-drilling project in an area under U.S. control. Greg Flakus reports.
Video

Video Philippine Maritime Police: Chinese Fishermen a Threat to Country’s Security

China and the Philippines both claim maritime rights in the South China Sea.  That includes the right to fish in those waters. Jason Strother reports on how the Philippines is catching Chinese nationals it says are illegal poachers. He has the story from Palawan province.
Video

Video Technique May Eliminate Drill-and-Fill Dental Care

Many people dread visiting dentists because they're afraid of drills. Now, however, a technology developed by a British firm promises to eliminate the need for mechanical cleaning of dental cavities by speeding a natural process of tooth repair. VOA’s George Putic reports.
Video

Video China's Spratly Island Building Said to Light Up the Night 'Like A City'

Southeast Asian countries claim China has illegally seized territory in the Spratly islands. It is especially a concern for a Philippine mayor who says Beijing is occupying parts of his municipality. Jason Strother reports from the capital of Palawan province, Puerto Princesa.
Video

Video Ages-old Ice Reveals Secrets of Climate Change

Ice caps don't just exist at the world's poles. There are also tropical ice caps, and the largest sits atop the Peruvian Andes - but it is melting, quickly, and may be gone within the next 20 years. George Putic reports scientists are now rushing to take samples to get at the valuable information about climate change locked in the ice.
Video

Video French Experiment in Integrating Roma Under Threat

Plans to destroy France’s oldest slum have sparked an outcry on the part of its Roma residents. As Lisa Bryant reports from the Paris suburb of La Courneuve, rights groups argue the community is a fledgling experiment on integrating Roma who are often outcasts in many parts of Europe.
Video

Video Kenyans Turn to Agriculture for Business

Each year Kenyan universities continue to churn out graduates for the job market despite the already existing high rate of unemployment among youth in the country. Some of these young men and women have realized that agriculture can be as rewarding as any other business or job, and they are resorting to agribusiness in large numbers as a way of tackling unemployment. Rael Ombuor reports for VOA.
Video

Video First Women Graduate Elite Army Ranger School

Two women are making history for the U.S. Army by proving they are among the toughest of the tough. VOA's Carla Babb reports from Fort Benning, Georgia as 94 men and those two women rise as graduates of the difficult Ranger school.

VOA Blogs