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 Molecular Force Sensors
20.09.2017 | Max-Planck-Institut für Biochemie

nachricht Foster tadpoles trigger parental instinct in poison frogs
20.09.2017 | Veterinärmedizinische Universität Wien

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

Im Focus: Silencing bacteria

HZI researchers pave the way for new agents that render hospital pathogens mute

Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Molecular Force Sensors

20.09.2017 | Life Sciences

Producing electricity during flight

20.09.2017 | Power and Electrical Engineering

Tiny lasers from a gallery of whispers

20.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>