Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Emory scientists find marker for long-term immunity

21.11.2003


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."

Holly Korschun | EurekAlert!
Further information:
http://www.emory.edu/

More articles from Life Sciences:

nachricht Navigational view of the brain thanks to powerful X-rays
18.10.2017 | Georgia Institute of Technology

nachricht Separating methane and CO2 will become more efficient
18.10.2017 | KU Leuven

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Osaka university researchers make the slipperiest surfaces adhesive

18.10.2017 | Materials Sciences

Space radiation won't stop NASA's human exploration

18.10.2017 | Physics and Astronomy

Los Alamos researchers and supercomputers help interpret the latest LIGO findings

18.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>