Featured Research

from universities, journals, and other organizations

SIV-resistant monkeys close the gates to viral infection

Date:
June 29, 2011
Source:
Emory University
Summary:
Sooty mangabeys, a type of African monkey, can survive infection by SIV, a relative of HIV, and not succumb to AIDS. Researchers have now identified a way some of sooty mangabeys' immune cells resist infection: they close the gates that SIV and HIV use to get into the cell. The findings may lead to strategies to help HIV-infected individuals cope better with infection.

Sooty mangabeys, a type of African monkey, have intrigued scientists for years because they can survive infection by SIV, a relative of HIV, and not succumb to AIDS.

Related Articles


Researchers have identified a way some of sooty mangabeys' immune cells resist infection: they close the gates that SIV and HIV use to get into the cell. The findings may lead to strategies to help HIV-infected individuals cope better with infection.

The results are published online in the journal Nature Medicine.

"We have shown sooty mangabeys can prevent SIV from infecting a very important part of the immune system," says first author Mirko Paiardini, PhD, senior research scientist at Yerkes National Primate Research Center, Emory University. "This protection from infection comes from reducing the levels on the cell surface of a molecule that SIV uses to enter the cell."

Co-first author is postdoctoral fellow Barbara Cervasi. The senior author is Guido Silvestri, MD, chief of microbiology and immunology at Yerkes National Primate Research Center, Emory University. Collaborators included investigators from NIH, University of Pennsylvania, University of Pittsburgh and University Hospital Ulm.

To infect a cell, HIV and SIV need to find two molecules on the cell's surface. Scientists call these molecules co-receptors, and they can be thought of as gates. One of the co-receptors is CD4, which appears on immune cells called T cells. The other is called CCR5. Stimulating a T cell usually increases the level of CCR5, facilitating infection.

Paiardini, Cervasi and their colleagues found that in sooty mangabeys, a type of T cell called a central memory T cell doesn't turn on CCR5. This means that even when a sooty mangabey is infected with SIV, some T cells can mostly avoid being killed by the virus.

Memory T cells help the immune system respond to an infection faster and stronger the second time around. Central memory T cells are long-lived and found in lymph nodes, in contrast to effector memory T cells, which have shorter life spans and are found mostly in tissues, such as the intestines, Paiardini says.

"Not all T cells are created equal," he says. "Some appear to be more important than others for keeping the immune system up and running. This is why having central memory T cells resistant to infection is so valuable. By protecting central memory T cells, sooty mangabeys avoid the loss of T cells and the chronic immune activation that are the hallmarks of AIDS in humans."

Scientists have identified several differences in the pattern of infection between sooty mangabeys and both humans and rhesus macaques, a monkey that is susceptible to SIV infection.

"For several years, we and others thought lack of chronic immune activation was the main factor protecting sooty mangabeys from AIDS," Paiardini says. "This study changes this working model and proposes that lack of immune activation in sooty mangabey is secondary, deriving from their ability to protect and maintain their central memory T cells."

Paiardini continues, "We would have not been able to perform such complex comparative studies without the presence of the large colony of sooty mangabeys at the Yerkes National Primate Research Center."

The National Institutes of Health supported this research.


Story Source:

The above story is based on materials provided by Emory University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Mirko Paiardini, Barbara Cervasi, Elane Reyes-Aviles, Luca Micci, Alexandra M Ortiz, Ann Chahroudi, Carol Vinton, Shari N Gordon, Steven E Bosinger, Nicholas Francella, Paul L Hallberg, Elizabeth Cramer, Timothy Schlub, Ming Liang Chan, Nadeene E Riddick, Ronald G Collman, Cristian Apetrei, Ivona Pandrea, James Else, Jan Munch, Frank Kirchhoff, Miles P Davenport, Jason M Brenchley, Guido Silvestri. Low levels of SIV infection in sooty mangabey central memory CD4 T cells are associated with limited CCR5 expression. Nature Medicine, 2011; DOI: 10.1038/nm.2395

Cite This Page:

Emory University. "SIV-resistant monkeys close the gates to viral infection." ScienceDaily. ScienceDaily, 29 June 2011. <www.sciencedaily.com/releases/2011/06/110627095801.htm>.
Emory University. (2011, June 29). SIV-resistant monkeys close the gates to viral infection. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2011/06/110627095801.htm
Emory University. "SIV-resistant monkeys close the gates to viral infection." ScienceDaily. www.sciencedaily.com/releases/2011/06/110627095801.htm (accessed October 25, 2014).

Share This



More Health & Medicine News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com
WHO: Millions of Ebola Vaccine Doses by 2015

WHO: Millions of Ebola Vaccine Doses by 2015

AP (Oct. 24, 2014) The World Health Organization said on Friday that millions of doses of two experimental Ebola vaccines could be ready for use in 2015 and five more experimental vaccines would start being tested in March. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Doctor in NYC Quarantined With Ebola

Doctor in NYC Quarantined With Ebola

AP (Oct. 24, 2014) An emergency room doctor who recently returned to the city after treating Ebola patients in West Africa has tested positive for the virus. He's quarantined in a hospital. (Oct. 24) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins