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 A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich

nachricht New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Switched-on DNA

20.02.2017 | Materials Sciences

Second cause of hidden hearing loss identified

20.02.2017 | Health and Medicine

Prospect for more effective treatment of nerve pain

20.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>