Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Adaptive regulatory T cells suppress killing of persistently infected cells

17.03.2004


Scientists report that they have identified a cellular mechanism that prevents the immune system from destroying chronic, incurable viral infections such as herpes, hepatitis and human immunodeficiency virus (HIV). The research, published in the March issue of Immunity, explains why critical immune cells fail to act against the viral infection and demonstrates a successful intervention that facilitates elimination of the virus. The results open up exciting new avenues for design of future antiviral therapeutics.



Many human viruses are able to evade the immune system during acute infection and establish long-term persistent infections that are extremely difficult to eliminate. Most of the time, proliferation of the virus is balanced by antiviral immunity and the host experiences little to no damage. However, persistent infections with viruses such as HIV or hepatitis lead to life threatening diseases that currently have no cure.

Immune cells called CD8+ T cells are critical for recovery from viral infections and persistent viral infections are associated with a malfunction of these cells that is not well understood. Dr. Kim J. Hasenkrug from the Rocky Mountain Laboratories, part of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health, and colleagues investigated persistent infection of mice with Friend virus (FV) to look at the specific mechanisms that contribute to CD8+ T cell dysfunction. The researchers found that although the CD8+ T cells could recognize their appropriate targets they could not destroy them. The key finding was that regulatory CD4+ T cells suppress the normal function of the CD8+ T cells in the persistently infected mice. Importantly, suppressing the activity of the regulatory CD4+ cells could prevent dysfunction of CD8+ T cells.


The researchers conclude that CD4+ T cells contribute to viral persistence by suppressing the host CD8+ T cell response and that influencing the activity of CD4+ T cells can reduce this suppression. "A practical intervention that could reduce virus loads during chronic HIV infection would likely be an invaluable tool in postponing the onset of AIDS. While it remains to be seen whether an intervention such as described in our study would work in HIV infections, our experiments open new possibilities of therapy for treating persistence, one of the most refractory elements of retroviral infections," explains Dr.Hasenkrug.

Ulf Dittmer, Hong He, Ronald J. Messer, Simone Schimmer, Anke R.M. Olbrich, Claes Ohlen, Philip D. Greenberg, Ingunn M. Stromnes, Michihiro Iwashiro, Shimon Sakaguchi, Leonard H. Evans, Karin E. Peterson, Guojun Yang, and Kim J. Hasenkrug: "Functional Impairment of CD8+ T Cells by Regulatory T Cells during Persistent Retroviral Infection"

Published in Immunity, Volume 20, Number 3, March 2004, pages 293-304.

Heidi Hardman | EurekAlert!
Further information:
http://www.cell.com/

More articles from Life Sciences:

nachricht Decoding the genome's cryptic language
27.02.2017 | University of California - San Diego

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Safe glide at total engine failure with ELA-inside

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...

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...

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

New pop-up strategy inspired by cuts, not folds

27.02.2017 | Materials Sciences

Sandia uses confined nanoparticles to improve hydrogen storage materials performance

27.02.2017 | Interdisciplinary Research

Decoding the genome's cryptic language

27.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>