Featured Research

from universities, journals, and other organizations

Emory Scientists Find Marker For Long-term Immunity

Date:
November 25, 2003
Source:
Emory University Health Sciences Center
Summary:
Scientists at the Emory Vaccine Center and The Scripps Research Institute have found a way to identify which of the T cells generated after a viral infection can persist and confer protective immunity.

Scientists at the Emory Vaccine Center and The Scripps Research Institute have found a way to identify which of the T cells generated after a viral infection can persist and confer protective immunity. Because these long-lived cells protect against reinfection by "remembering" the prior pathogen, they are called memory T cells. This discovery about the specific mechanisms of long-term immunity could help scientists develop more effective vaccines against challenging infections.

The research, by Susan M. Kaech, PhD, a postdoctoral fellow in microbiology and immunology at Emory University School of Medicine, and principal investigator Rafi Ahmed, PhD, director of the Emory Vaccine Center and a Georgia Research Eminent Scholar, was published online November 16 and will be printed in the December issue of Nature Immunology. Other members of the research team were E. John Wherry and Bogumila T. Konieczny of Emory University School of Medicine, and Joyce T. Tan and Charles D. Surh of The Scripps Research Institute.

During an acute viral infection, CD4 and CD8 T cells activated by specific viral antigens dramatically expand in number and become effector T cells. These cells kill the virus-infected cells and also produce cytokines. Most effector cells die within a few weeks, after their initial job is complete. Only about 5 to 10 percent survive to become long-term memory cells, which are capable of mounting a strong and rapid immune response when they come into contact with the original virus, even years later. Scientists have not clearly understood the mechanisms of memory cell production, and a major unanswered question has been how to distinguish the small fraction of cells likely to survive in long-term memory.

This team of investigators found that expression of the interleukin 7 (IL-7) receptor, which binds the cytokine IL-7 and is required for T cell survival, is increased in a small subset of CD8 T cells generated during an acute infection, and that expression of this receptor marks those that will survive to become long-lived memory CD8 T cells.

In experiments with mice, the Emory scientists found that at the peak of the CD8 T cell immune response during an acute viral infection a small subset of effector cells had a higher expression of the IL-7 receptor, and they hypothesized that these cells would be the ones to survive as memory cells. They transferred a group of cells with and without this distinguishing characteristic into mice that were unexposed to virus, and found that in fact the cells expressing IL-7 receptor survived and differentiated into long-lived memory cells. They also found that IL-7 signals were necessary for the survival of these cells.

"We can consider the IL-7 receptor a marker of 'cellular fitness' for long-term survival and functionality," says Dr. Kaech. "This new knowledge should help us in assessing and predicting the number and quality of memory T cells that will be generated after infection or immunization. It also could lead to the identification of additional markers of memory cells and provide a more comprehensive picture of memory cell development."

"As scientists struggle to create long-term, effective vaccines for difficult diseases, they need a detailed understanding of the mechanisms of long-term memory," says Dr. Ahmed. "Understanding immune memory is the necessary basis for developing any type of effective vaccine. In addition, these findings could help in designing immunotherapies to control chronic viral infections and cancer."


Story Source:

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


Cite This Page:

Emory University Health Sciences Center. "Emory Scientists Find Marker For Long-term Immunity." ScienceDaily. ScienceDaily, 25 November 2003. <www.sciencedaily.com/releases/2003/11/031121071431.htm>.
Emory University Health Sciences Center. (2003, November 25). Emory Scientists Find Marker For Long-term Immunity. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2003/11/031121071431.htm
Emory University Health Sciences Center. "Emory Scientists Find Marker For Long-term Immunity." ScienceDaily. www.sciencedaily.com/releases/2003/11/031121071431.htm (accessed October 20, 2014).

Share This



More Health & Medicine News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Microneedle Patch Promises Painless Pricks

Microneedle Patch Promises Painless Pricks

Reuters - Innovations Video Online (Oct. 18, 2014) Researchers at The National University of Singapore have invented a new microneedle patch that could offer a faster and less painful delivery of drugs such as insulin and painkillers. Video provided by Reuters
Powered by NewsLook.com
Raw: Nurse Nina Pham Arrives in Maryland

Raw: Nurse Nina Pham Arrives in Maryland

AP (Oct. 17, 2014) The first nurse to be diagnosed with Ebola at a Dallas hospital walked down the stairs of an executive jet into an ambulance at an airport in Frederick, Maryland, on Thursday. Pham will be treated at the National Institutes of Health. (Oct. 16) Video provided by AP
Powered by NewsLook.com
Raw: Cruise Ship Returns to US Over Ebola Fears

Raw: Cruise Ship Returns to US Over Ebola Fears

AP (Oct. 17, 2014) A Caribbean cruise ship carrying a Dallas health care worker who is being monitored for signs of the Ebola virus is heading back to Texas, US, after being refused permission to dock in Cozumel, Mexico. (Oct. 17) Video provided by AP
Powered by NewsLook.com
Spanish Govt: Four Suspected Ebola Cases in Spain Test Negative

Spanish Govt: Four Suspected Ebola Cases in Spain Test Negative

AFP (Oct. 17, 2014) All four suspected Ebola cases admitted to hospitals in Spain on Thursday have tested negative for the deadly virus in a first round of tests, the government said Friday. Duration: 00:55 Video provided by AFP
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