Navigation Links
HIV handicaps itself to escape immune system pressure
Date:4/15/2009

People with the ability to stave off AIDS for years after initial infection by HIV have been called "long-term non-progressors" or "elite controllers."

One component of this remarkable resistance comes from an individual's HLA genes. Long-term non-progressors tend to have HLA genes that help the immune system recognize and fight HIV more efficiently.

A team of researchers from the Emory Vaccine Center studying HIV-infected people with particularly effective HLA genes has observed how the virus mutates and evolves in response to immune pressure.

The observations, published in the Journal of Experimental Medicine, can provide guidance on what kinds of immune responses a successful HIV vaccine should generate.

The team was led by Eric Hunter, PhD, professor of pathology and laboratory medicine at Emory University School of Medicine, Emory Vaccine Center, and Yerkes National Primate Research Center. Hunter is a Georgia Research Alliance Eminent Scholar. First author Hayley Crawford, a graduate student at Oxford University, England, performed much of the research while working in Hunter's laboratory.

The Emory/Oxford team studied people in Zambia and South Africa with one form of the HLA gene that helps the immune system control HIV, called HLA-B*5703.

HLA genes encode molecules that display fragments of viral proteins, known as epitopes, on the surface of infected cells. When white blood cells known as cytotoxic T lymphocytes (CTLs) spot certain combinations of HLA molecules and viral epitopes, they attack the infected cells.

The authors show that a set of three mutations in HIV's Gag protein, which makes up the viral core, progressively slow viral replication. In cell culture, a triple-mutant virus replicates 20 times slower than normal. However, these same mutations effectively eliminate the ability of CTLs to detect the virus. so that in an infected person, once all three mutations are in place, viral abundance shoots upwards.

"In this situation, HIV resembles a thief picking a lock. Once all three mutations are in place, the lock is picked and the virus can thrive because the immune system can't fight against it," Hunter says.

The team followed the mutations' fate after transmission by studying couples in which one person had infected the other. If the recipient lacked HLA-B*5703, the virus lost the mutations, because the three handicapping mutations were not useful in evading the new, different immune system. But unlucky recipients with HLA-B*5703 who got the triple-mutant virus from their partners quickly got sick.

The results demonstrate the importance of CTLs, the white blood cells that attack viral infected cells, in controlling HIV infection. They also suggest that a successful vaccine will need to induce responses to many epitopes, or combinations of HLA molecule and viral protein.


'/>"/>

Contact: Holly Korschun
hkorsch@emory.edu
404-727-3990
Emory University
Source:Eurekalert

Related medicine news :

1. For Some, Diabetes Care Worse Than Illness Itself
2. Galderma Associates Itself to Cartiers Womens Initiative Awards to Recognize Female Entrepreneurs From Around the Globe
3. Higher Balance Institute Forced to File Suit to Defend Itself
4. Weizmann Institute scientists discover how an injured embryo can regenerate itself
5. Genesis Pharmaceuticals Successfully Defends Itself in a Multi-Million Dollar Arbitration, Two Other Arbitration Proceedings Against Genesis are Withdrawn
6. Virtual game helps children escape realities of burn unit
7. Escape the Cold and Flu Season With a Free Vacation to the Sunshine State
8. Defending Champions Andy Potts and Leanda Cave Win 28th Annual Accenture Escape From Alcatraz(TM) Triathlon Sunday, June 8
9. Yo Mujer: Woman Escapes from Abusive Marriage in New Spanish-Language Novel
10. Escape cancer, but age sooner? The dark side of the tumor suppressing process
11. Penn study finds pro-death proteins required to regulate healthy immune function
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/25/2016)... , ... June 25, 2016 , ... "With 30 hand-drawn ... specific project," said Christina Austin - CEO of Pixel Film Studios. , ProHand ... all within Final Cut Pro X . Simply select a ProHand generator and ...
(Date:6/25/2016)... ... June 25, 2016 , ... On Friday, June 10, Van Mitchell, ... at Work award to iHire in recognition of their exemplary accomplishments in worksite health ... annual Maryland Workplace Health & Wellness Symposium at the BWI Marriott in Linthicum Heights. ...
(Date:6/24/2016)... ... June 24, 2016 , ... June 19, 2016 is World Sickle Cell ... pain and the benefits of holistic treatments, Serenity Recovery Center of Marne, ... Cell Disease. , Sickle Cell Disease (SCD) is a disorder of the red blood ...
(Date:6/24/2016)... (PRWEB) , ... June 24, 2016 , ... ... now offering micro-osteoperforation for accelerated orthodontic treatment. Dr. Cheng has extensive experience with ... Damon brackets , AcceleDent, and accelerated osteogenic orthodontics. , Micro-osteoperforation is a ...
(Date:6/24/2016)... ... 2016 , ... EB Medicine presented its first-ever “Issue of ... in Ponte Vedra Beach, FL. The awards honor the outstanding work of leading ... and Pediatric Emergency Medicine Practice. , “With this award, we recognize the efforts ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... , June 23, 2016 Bracket , a ... its next generation clinical outcomes platform, Bracket eCOA (SM) ... on June 26 – 30, 2016 in Philadelphia ... electronic Clinical Outcome Assessment product of its kind to fully ... Bracket eCOA 6.0 is a flexible platform for ...
(Date:6/23/2016)... and INDIANAPOLIS , June ... receiving a Lilly Diabetes Tomorrow,s Leaders Scholarship is any ... scholarship winners, announced today online at www.diabetesscholars.org ... type 1 diabetes stand in the way of academic ... supported the Foundation,s scholarship program since 2012, and continues ...
(Date:6/23/2016)... June 23, 2016 Revolutionary technology ... Oticon , industry leaders in advanced audiology and ... Oticon Opn ™, the world,s first internet connected ... for IoT devices.      (Photo: http://photos.prnewswire.com/prnh/20160622/382240 ... a number of ,world firsts,: , TwinLink™ ...
Breaking Medicine Technology: