Too much of a protein called c-FLIPR can trigger autoimmune diseases
As strange as it may seem, a process called "cellular suicide" is actually crucial for the survival of the entire body. A protein called c-FLIPR plays a key role in controlling this process, which is called "apoptosis".
Scientists at the Helmholtz Centre for Infection Research (HZI) have described the significance of c-FLIPR for the immune system in more detail: In the presence of an excess of this molecule, mice can fight infectious diseases better, but they develop autoimmune diseases as they get older. The inhibitory effect of c-FLIPR on apoptosis is the underlying cause of both these effects.
Apoptosis is used by cells that are changed by disease or are simply not needed any longer to eliminate themselves before they become a hazard to the body—on a cellular level, death is part of life. Disruption of this process can lead to cancer or immunodeficiencies, but also to autoimmune diseases, in which cells attack their own body.
HZI scientist Prof Ingo Schmitz and his team investigate the regulation of apoptosis in the immune system. In collaboration with researchers of the Otto von Guericke University Magdeburg and the Helmholtz Zentrum München, they elucidated the role of a central protein in this process.
The researchers published their results in "Cell Death & Disease". So-called c-FLIP proteins inhibit signaling cascades that can lead to apoptosis. This is important temporarily in the response to pathogens to ensure that lymphocytes, a type of immune cells, can proliferate sufficiently. Towards the end of the immune response, once the lymphocytes completed their tasks and successfully eliminated the pathogen, c-FLIP is usually degraded. As a result, apoptosis is enabled again, the lymphocytes die and the equilibrium in the immune system is restored.
The HZI researchers then took a closer look at the exact function of a certain variant of the protein, called c-FLIPR. They used mice to investigate what happens if this protein is always present in lymphocytes and other blood cells. Whereas the apoptosis inhibitor caused no anomalies in young mice, the scenario in older mice was quite different: "The composition of the lymphocytes was changed significantly," says Schmitz. "Furthermore the immune cells were strongly activated."
The overactivation is easily apparent in the body. The researchers found immune molecules, called autoantibodies, which attack the body's own tissue in the kidneys and lung. In addition, they detected harmful protein deposits in the kidneys. The changes in the lung tissue are also indicative of the immune system attacking its own body in the presence of too much c-FLIPR. "Immune cells migrate into the lung and attack the lung tissue," says Schmitz. Physicians usually see these symptoms in a human autoimmune disease called systemic lupus erythematosus
The HZI scientists discovered already last year that cells can fight bacterial infections better if c-FLIPR is turned on permanently. This means that inhibiting the suicide of cells has beneficial effects in acute infections, but leads to autoimmune reactions in the long run. "c-FLIPR is important for the balance of the immune system. It might be possible to intervene with suitable therapeutic agents if the equilibrium of the immune system is disrupted," says Schmitz.
Frida Ewald, Michaela Annemann, Marina C. Pils, Carlos Plaza-Sirvent, Frauke Neff, Christian Erck, Dirk Reinhold, Ingo Schmitz
Constitutive expression of murine c-FLIPR causes autoimmunity in aged mice
Cell Death & Disease, 2014
The research group "Systems-oriented Immunology and Inflammation Research" studies the molecular processes that sensitize immune cells to the body’s own tissues. A main focus is on the cellular suicide programme apoptosis.
The Helmholtz Centre for Infection Research (HZI)
Scientists at the Helmholtz Centre for Infection Research in Braunschweig, Germany, are engaged in the study of different mechanisms of infection and of the body’s response to infection. Helping to improve the scientific community’s understanding of a given bacterium’s or virus’ pathogenicity is key to developing effective new treatments and vaccines.
Dr. Birgit Manno | Helmholtz-Zentrum
First-time reconstruction of infectious bat influenza viruses
25.10.2016 | Universitätsklinikum Freiburg
The nanostructured cloak of invisibility
25.10.2016 | Max-Planck-Institut für Intelligente Systeme
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
25.10.2016 | Life Sciences
24.10.2016 | Earth Sciences
24.10.2016 | Life Sciences