Charité Physicians Portal 

Meta menu:

From here, you can access the Emergencies page, Contact Us page, Accessibility Settings, Language Selection, and Search page.

Open Menu
Nahaufname einer Tageszeitung mit Tiefenunschärfe. Die obersten Seiten sind zusammelgerollt.

Press release

16.02.2012

Successful Basic Research on Defense against Infections and Cancer

Back to Overview

You are here:

Scientists discover new defense mechanism

picture.jpg
Cells dying from an infectious virus alarm killer T cells. Dendritic cells infected with a virus deliver the first activation signal for killer T cells through their T-cell receptors. Scientists discovered, that virus infected, dying cells also alarm killer T cells. Due to the viral infection, dying cells release the alarmin interleukin-33. This second signal leads to the complete activation of killer T cells. They reproduce quickly and effectively kill the cells infected with the virus.

Research groups from Charité Universitätsmedizin Berlin and the University of Geneva have discovered a new way of improving vaccines against infectious diseases and for use in cancer therapies. Scientists have shown a basic new mechanism that stimulates the body’s own alarm signals in case of viral infection to animate the immune system to maximum performance.

Viral infections activate so-called killer T cells. These form an important part of the body’s defense. They can recognize and destroy cells that are infected with viruses or have degenerated into cancer cells. Thus, killer T cells would be an important mechanism in vaccines against HIV/AIDS, hepatitis C, malaria, and in cancer therapies. To date, there are no vaccines available for any of these diseases. Killer T cells are activated by dendritic cells. These coordinate the body’s immune response.

The German-Swiss research group, surrounding Prof. Max Löhning from Charité and Prof. Daniel Pinschewer from University of Geneva, has now discovered a second mechanism that indicates how a viral infection stimulates killer T cells to maximum performance. Prof. Löhning explains: “The virus-infected, dying cells ring the alarm bells to the killer T cells themselves.

"When viruses destroy infected cells, cell matter is released that is usually invisible to killer T cells. This matter includes so-called alarmins. The scientists have discovered that killer T cells recognize the alarmin interleukin-33. In case of cell death, the cells that form the framework of the spleen and lymph nodes and are in direct proximity to killer T cells, release this alarmin.

In experiments with mice, researchers determined that mice missing the interleukin-33 gene failed to generate large numbers of killer T cells upon viral infection. The few cells remaining were only barely active. Conversely, administering the relevant alarmin during vaccination led to a large increase in killer T cells. These new findings form an important basis for the development of effective vaccines against infectious diseases and for cancer therapies.

Downloads

picture.jpg

50 KB  

Cells dying from an infectious virus alarm killer T cells. Dendritic cells infected with a virus deliver the first activation signal for killer T cells through their T-cell receptors. Scientists discovered, that virus infected, dying cells also alarm killer T cells. Due to the viral infection, dying cells release the alarmin interleukin-33. This second signal leads to the complete activation of killer T cells. They reproduce quickly and effectively kill the cells infected with the virus.

Links

Link to article:
http://www.sciencemag.org/content/early/2012/02/08/science.1215418.abstract

Link to clinic:
http://rheumatologie.charite.de/

Contact

Prof. Max Löhning
Medizinische Klinik mit Schwerpunkten Rheumatologie und Klinische Immunologie
Charité – Universitätsmedizin Berlin   
t: +49 30 2846 0760



Back to Overview