Navigation Links
Research suggests HIV causes rapid aging in key infection-fighting cells
Date:1/27/2011

In the early years of the AIDS epidemic, being infected with the virus that causes the disease was considered a virtual death sentence. But with the development of antiretroviral therapy, many with HIV are now living much longer. In fact, it is estimated that by 2015, about half of all HIV-positive individuals will be older than 50.

Yet those over 50 also progress to AIDS faster than adults in their 20s or 30s. And those in the younger age bracket even those responding well to antiretroviral therapy still exhibit illnesses and clinical conditions commonly associated with older people, such as certain cancers and liver diseases. For the most part, the reasons for this have remained a mystery.

But a UCLA AIDS Institute study published Jan. 26 in the online journal PLoS ONE suggests a partial explanation, showing that HIV causes a specific subset of CD4+ "helper" T-cells which play an important role in the body's response to infection to age rapidly, by as much as 20 to 30 years over a three-year period.

In the study, researchers witnessed a decline in CD4+ T-cell numbers and, most strikingly, found that in the surviving T-cells, the HIV virus caused rapid and drastic shortening of the ends of chromosomes, called telomeres, which protect the chromosomes and prevent them from fusing together, much like plastic tips keep shoelaces from unraveling. Telomeres become progressively shorter during natural cell division; when they become too short, cells do not function properly.

"Our findings have important implications for the health of both young and old HIV-1infected adults," said lead investigator Tammy M. Rickabaugh, an assistant research immunologist in the division of hematology and oncology at the David Geffen School of Medicine at UCLA. "They underscore the importance of developing new approaches to boost immune function to complement current treatments, which are exclusively directed against the virus."

The researchers examined two subsets of CD4+ T-cells (CD45RA+ CD31+ and CD45RA+ CD31-) in two groups of individuals those aged 20󈞌 and those aged 39󈞦 who had been infected with HIV for one to three years and who had not been treated with antiretroviral therapy. They compared these two groups with samples from age-matched controls who were HIV seronegative.

The researchers specifically focused on "naive" T-cells those that had not previously encountered any pathogens and thus act as a reserve against future infections and cancers. They found that in individuals infected with HIV-1, these cells underwent unexpectedly rapid aging the equivalent of 20 to 30 years of aging within three years of infection. They also found that the number of CD31- T-cells, which are more quickly pulled into the fight against new pathogens, had fallen drastically.

The researchers also investigated whether appropriate treatment could reverse this aging effect. They examined cells from HIV-positive individuals who had been on antiretroviral therapy for two years and whose therapy had successfully kept HIV-1 under control. They found that while the therapy kept their viral loads at undetectable levels, it did not entirely restore their immune systems, suggesting a reason why younger HIV-positive people still become ill with conditions more common to older people.

"Taken together, our results help to explain some of the clinical observations that have been documented in HIV-infected people and emphasize the need for developing therapeutic approaches directed at improving the naive immune cell compartment," said senior investigator Beth D. Jamieson, an associate professor of medicine in the division of hematology and oncology at the David Geffen School of Medicine at UCLA. "This is critically important in light of the demographic shift of HIV-infected persons."


'/>"/>

Contact: Enrique Rivero
erivero@mednet.ucla.edu
310-794-2273
University of California - Los Angeles
Source:Eurekalert

Related biology news :

1. Wistar Institute researcher receives New Innovator award from NIH
2. NC State researchers get to root of parasite genome
3. White Mountain Research Station to host climate change conference
4. Stevens awarded $1M for advanced biofuels research
5. Researchers find animal with ability to survive climate change
6. Researchers find an essential gene for forming ears of corn
7. Researchers note differences between people and animals on calorie restriction
8. Researcher working on destruction of chemical weapons
9. Researchers study acoustic communication in deep-sea fish
10. Researchers discover that growing up too fast may mean dying young in honey bees
11. The Rett Syndrome Research Trust launches operations
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/22/2016)... Md. , June 22, 2016  The American College ... Trade Show Executive Magazine as one of the ... on May 25-27 at the Bellagio in Las ... on the highest percentage of growth in each of the ... of exhibiting companies and number of attendees. The 2015 ACMG ...
(Date:6/21/2016)... 2016 NuData Security announced today that Randy ... principal product architect and that Jon Cunningham ... development. Both will report directly to Christopher ... reflect NuData,s strategic growth in its product and ... demand and customer focus values. ...
(Date:6/15/2016)... 2016 Transparency Market Research ... Market by Application Market - Global Industry Analysis Size Share ... the report, the  global gesture recognition market  was ... is estimated to grow at a CAGR of ... Increasing application of gesture recognition technology ...
Breaking Biology News(10 mins):
(Date:12/2/2016)... ... December 01, 2016 , ... DrugDev believes the only way ... beautiful technology experience. All three tenets were on display at the 2nd Annual DrugDev ... over 40 sponsor, CRO and site organizations to discuss innovation and the future of ...
(Date:12/2/2016)... 2, 2016 The immunohistochemistry (IHC) market ... a CAGR of 7.3% during the forecast period of 2016 to ... laboratories segment accounted for the largest share of immunohistochemistry (IHC) market, ... , ... immunohistochemistry (IHC) market spread across 225 pages, profiling 10 companies and ...
(Date:11/30/2016)... 2016 /PRNewswire/ - Portage Biotech Inc. ("Portage" or "the ... excited to announce the formation of EyGen, Ltd. ... ophthalmology assets through proof of concept. EyGen,s lead ... Portage Pharmaceuticals Limited and being developed for topical ... anterior segment diseases. This agent has the potential ...
(Date:11/30/2016)... SAN DIEGO and BEIJING ... Ltd., a leading commercial provider of genomic services and ... expertise, announced today that it has completed a USD ... China Merchants Bank Co., Ltd.,s CMB International Capital Management ... SDIC Innovation Investment Management Co., Ltd. ("SDIC Innovation") and ...
Breaking Biology Technology: