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

At Khmer Rouge Court, Long-Awaited Verdict Approaches

First phase of trial, which is coming to an end, has focused on forced exodus of Phnom Penh in 1975 - and now many are hopeful justice will be served More

Video When Fighting Eases, Gazans Line Up at Bakeries

When there is a lull in the conflict, residents who have been hunkered down in their apartments rush out to stock up on food and other necessities More

Video Information War Rages Alongside Real One in Ukraine

Downing of Malaysian airliner, allegations of cross-border shelling move information war in war-torn country to a new level 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.
Information War Rages Alongside Real One in Ukrainei
X
Al Pessin
July 31, 2014 8:13 PM
The downing of the Malaysian airliner two weeks ago, and allegations that Russians are shelling Ukrainian troops across the border, have moved the information war swirling around the Ukrainian conflict to a new level. VOA's Al Pessin reports from Kyiv.
Video

Video Information War Rages Alongside Real One in Ukraine

The downing of the Malaysian airliner two weeks ago, and allegations that Russians are shelling Ukrainian troops across the border, have moved the information war swirling around the Ukrainian conflict to a new level. VOA's Al Pessin reports from Kyiv.
Video

Video When Fighting Eases, Gazans Line Up at Bakeries

When there is a lull in the conflict in Gaza, residents who have been hunkered down in their apartments rush out to stock up on food and other necessities. Probably the most important destination is the local bakery. VOA’s Scott Bobb reports from Gaza City.
Video

Video US-Funded Program Offers Honduran Children Alternative to Illegal Immigration

President Obama and Central American leaders recently agreed to come up with a plan to address poverty and crime in the region that is fueling the surge of young migrants trying to illegally enter the United States. VOA’s Brian Padden looks at one such program in Honduras - funded in part by the United States - which gives street kids not only food and safety but a chance for a better life without, crossing the border.
Video

Video 'Fab Lab' Igniting Revolution in Kenya

The University of Nairobi’s Science and Technology Park is banking on 3-D prototyping to spark a manufacturing revolution in the country. Lenny Ruvaga has more for from Nairobi's so-called “FabLab” for VOA.
Video

Video Gazans in Shelled School Sought Shelter

Israel's air and ground assault against Hamas-led fighters in Gaza has forced many Palestinians to flee their homes, seeking safety. But safe places are hard to find, as VOA’s Scott Bobb reports from Jabaliya.
Video

Video Rapid Spread of Ebola in West Africa Prompts Global Alert

Across West Africa, health officials are struggling to keep up with what the World Health Organization describes as the worst ebola outbreak on record. The virus has killed hundreds of people this year. U.S. President Barack Obama and other world leaders are watching the developments closely as they weigh what actions, if any, are needed to help contain the disease.
Video

Video Michelle Obama: Young Africans Need to Embrace Women's Rights

U.S. first lady Michelle Obama urged some of Africa's best and brightest to advocate for women's rights in their home countries. As VOA's Pam Dockins explains, Obama spoke to some 500 participants of the Young African Leaders Initiative, a six-week U.S.-based training and development program.
Video

Video Immigrant Influx on Texas Border Heats Up Political Debate

Immigrants from Central America continue to cross the U.S.-Mexico border in south Texas, seeking asylum in the United States, as officials grapple with ways to deal with the problem and provide shelter for thousands of minors among the illegal border crossers. As VOA's Greg Flakus reports from Houston, the issue is complicated by internal U.S. politics and U.S. relations with the troubled nations that immigrants are fleeing.
Video

Video Study: Latino Students Most Segregated in California

Even though legal school segregation ended in the United States 60 years ago, one study finds segregation still occurs in the U.S. based on income and race. The University of California Los Angeles Civil Rights Project finds that students in California are more segregated by race than ever before, especially Latinos. Elizabeth Lee reports for VOA from Los Angeles.

AppleAndroid