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 Building blocks for new medications: the University of Graz is seeking a technology partner
19.03.2019 | Karl-Franzens-Universität Graz

nachricht Scientists find new approach that shows promise for treating cystic fibrosis
14.03.2019 | NIH/National Heart, Lung and Blood Institute

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: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

Im Focus: Revealing the secret of the vacuum for the first time

New research group at the University of Jena combines theory and experiment to demonstrate for the first time certain physical processes in a quantum vacuum

For most people, a vacuum is an empty space. Quantum physics, on the other hand, assumes that even in this lowest-energy state, particles and antiparticles...

Im Focus: Sussex scientists one step closer to a clock that could replace GPS and Galileo

Physicists in the EPic Lab at University of Sussex make crucial development in global race to develop a portable atomic clock

Scientists in the Emergent Photonics Lab (EPic Lab) at the University of Sussex have made a breakthrough to a crucial element of an atomic clock - devices...

Im Focus: Sensing shakes

A new way to sense earthquakes could help improve early warning systems

Every year earthquakes worldwide claim hundreds or even thousands of lives. Forewarning allows people to head for safety and a matter of seconds could spell...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Levitating objects with light

19.03.2019 | Physics and Astronomy

New technique for in-cell distance determination

19.03.2019 | Life Sciences

Stellar cartography

19.03.2019 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>