Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Autoimmunity and Infections: When the Body Fights Itself

06.01.2017

Basel-based doctors are on the trail of a possible connection between autoimmune diseases and infections: errors can occur when immune cells absorb certain proteins from pathogen cells. These findings were reported in the journal PNAS by researchers from the Department of Biomedicine at the University of Basel and University Hospital Basel, as well as colleagues in the USA.

It is already known that there is a connection between infections and autoimmunity – the inability of an organism to recognize parts of its own body as “self”. As a result, increasing hygiene is leading to a higher incidence of autoimmune diseases in the population.

It is also apparent that some autoimmune diseases are triggered by infections. However, the mechanism behind these connections is still not fully understood. One possible explanation is that the immune system confuses protein structures from pathogens with the body’s own proteins because they look structurally alike.

Errors in protein uptake

Together with colleagues from the Whitehead Institute in Cambridge (USA), the Basel-based team of researchers tested out a new hypothesis in experiments to investigate the special ability of immune cells to identify specific proteins on the surface of neighboring cells and capture them from the cell membrane. In certain cases, errors can occur in the uptake of these proteins, as the group led by Professor Tobias Derfuss has now demonstrated.

Their assumption is that certain immune cells, so-called B cells, capture not only the protein of an influenza virus for which they were specialized, but also small quantities of other neighboring membrane proteins. One example of this is a protein known as an autoantigen that originates from the cell membrane layer in the central nervous system. An immune response to this membrane protein results in an autoimmune inflammation in the brain in the animal model and may well also contribute to inflammation of this kind in humans.

Harmful immune cells

B cells cultivated with cells that had incorporated both the influenza virus protein and the membrane protein were not only able to activate other immune cells, specifically certain T cells, in order to combat the virus; they also activated T cells that had recognized the body’s own membrane protein – which can trigger autoimmune inflammation in the brain. Consequently, a viral infection could lead to the activation of autoaggressive T cells through an error in the protein uptake of B cells.

The researchers discovered this mechanism after conducting experiments using cells from genetically modified mice. “The next step would now be to examine whether similar errors occur in protein uptake by human B cells. We also want to clarify whether a viral infection in an animal can, under certain circumstances, lead to autoimmune inflammation in the brain,” says Derfuss. Corresponding follow-up projects are planned.

Original paper
Nicholas S.R. Sanderson, Maria Zimmermann, Luca Eilinger, Céline Osswald, Nicole Schaeren-Wiemers, Raija L.P. Lindberg, Stephanie K. Dougan, Hidde Ploegh, Ludwig Kappos, and Tobias Derfuss
“Co-capture of cognate and bystander antigens can activate autoreactive B cells”
PNAS, Early Edition, January 5, 2017 | doi: 10.1073/pnas.1612062114

Further information
Professor Tobias Derfuss, Department of Biomedicine at the University of Basel and University Hospital Basel, Tel. ++41 61 328 67 26; Email: tobias.derfuss@usb.ch

Weitere Informationen:

http://www.pnas.org/content/early/2017/01/04/1614472114 - Abstract

lic. phil. Christoph Dieffenbacher | Universität Basel
Further information:
http://www.unibas.ch

More articles from Health and Medicine:

nachricht GLUT5 fluorescent probe fingerprints cancer cells
20.04.2018 | Michigan Technological University

nachricht Scientists re-create brain neurons to study obesity and personalize treatment
20.04.2018 | Cedars-Sinai Medical Center

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Magnetic nano-imaging on a table top

20.04.2018 | Physics and Astronomy

Start of work for the world's largest electric truck

20.04.2018 | Interdisciplinary Research

Atoms may hum a tune from grand cosmic symphony

20.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>