Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

How the body senses emergency

12.01.2009
A receptor, induced on the surface of macrophages under stressful conditions, can detect tissue injury, stimulating inflammation and possibly repair, a RIKEN-led team of molecular biologists has discovered. Their work could provide new leads for anti-inflammatory drugs and healing.

A receptor on macrophages can detect excessive cell death and recruit help

A receptor, induced on the surface of macrophages under stressful conditions, can detect tissue injury, stimulating inflammation and possibly repair, a RIKEN-led team of molecular biologists has discovered. Their work could provide new leads for anti-inflammatory drugs and healing.

Stress, age and body maintenance generate a continuous supply of dead cells, which normally are cleaned up by the macrophages that engulf pathogens and cellular debris. This mechanism, however, becomes overwhelmed at times of large-scale tissue damage, such as that caused by radiation or injury. To deal with such emergencies, the body needs a sensor which not only can detect the scale of the problem, but also that the dead tissue is not foreign.

Earlier research by another group had suggested that cellular stress leads to an upsurge in the activity of a gene, Mincle, which codes for a surface receptor in macrophages. So the RIKEN-led research team investigated the function of this receptor further. Their findings were published recently in Nature Immunology (1).

Initially, the researchers found that the Mincle receptor is associated with another signaling receptor chain, FcRã and triggers macrophage activation through a specific sequence known as the immunoreceptor tyrosine-based activation motif (ITAM). This stimulates the release of cellular hormones—cytokines and chemokines—that summon neutrophils to take part in inflammation and possibly tissue repair. Using a system involving green fluorescent protein to detect ITAM-mediated cell activation, the researchers found that Mincle responds to the presence of dead cells.

They then purified protein material from dead cells bound to the Mincle receptor, and discovered it was SAP130, a protein found in cell nuclei. SAP130 is released from cells where it can come into contact with the Mincle receptor only after they die and break down. In further experiments, the researchers determined the Mincle alert system works in mammals by showing that in living mice in which thymus cells had been killed by irradiation, the recruitment of neutrophils to the site of the damage was prevented by Mincle-specific antibody.

According to the team leader, Takashi Saito of the RIKEN Center for Allergy and Immunology in Yokohama, the research group now wants to determine the role of the alert system in diseases involving tissue damage; how activation of Mincle is related to the induction of autoimmune diseases such as rheumatoid arthritis; and whether it is possible to inhibit or cure inflammation and/or autoimmune diseases by blocking Mincle.

Reference

1. Yamasaki, S., Ishikawa, E., Sakuma, M., Hara, H., Ogata, K. & Saito, T. Mincle is an ITAM-coupled activating receptor that senses damaged cells. Nature Immunology 9, 1179–1188 (2008).

The corresponding author for this highlight is based at the RIKEN Laboratory for Cell Signaling

Saeko Okada | ResearchSEA
Further information:
http://www.rikenresearch.riken.jp/research/611/
http://www.researchsea.com

More articles from Life Sciences:

nachricht Fine organic particles in the atmosphere are more often solid glass beads than liquid oil droplets
21.04.2017 | Max-Planck-Institut für Chemie

nachricht Study overturns seminal research about the developing nervous system
21.04.2017 | University of California - Los Angeles Health Sciences

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>