Researchers from Aarhus University, Denmark, have now discovered an important mechanism behind one of our most fundamental lines of immune function. The discovery has been published in the esteemed scientific journal, The Journal of Immunology, where it has been highlighted as a top story.
In collaboration with colleagues from USA and Turkey, they have discovered exactly which enzymes collaborate in the first line of the immune defence. Thus, they answer a central question about the so-called complement system, which has been a focal point of the scientific field for the past decade: which enzyme does what?
Using blood samples from a unique patient harbouring a rare genetic syndrome, the researchers from Aarhus University have now established that it is the enzyme MASP-1 that is key to the activation of the complement system.
"Understanding the immune system is a central goal in itself in scientific terms, especially for our research group conducting basic research. But in the longer run, it is also an important goal that this knowledge may help people and cure diseases", says postdoc Soeren Egedal Degn from Aarhus University, who is first author on the paper.
Big perspectives for patients
He believes that once one has defined how the complement system works, it will be possible to manipulate it:
"For example this system is important for the survival of patients undergoing chemotherapy, because this treatment suppresses other functions of the immune system - so in their case it is beneficial to "rev up" the system. But following a heart attack there may be reasons to instead dampen the system. The complement system has an unfortunate tendency to attack tissues that have suffered damage due to deprivation of oxygen, and thereby it exacerbates the damage already done to the heart", says Soeren Egedal Degn.
He notes however, that the new discovery is unlikely to result in concrete new treatment modalities in this decade.
MASP-1 and the lectin pathway
Behind the discovery of the central role of MASP-1 in the complement system is, apart from Soeren Egedal Degn, also the Aarhus professors Jens Chr. Jensenius and Steffen Thiel, who are considered international experts in the field. They have previously discovered the four other known proteins related to MASP-1, namely MASP-2, MASP-3, MAp19 and MAp44. Together, these proteins make up a central part of the activation pathway of complement known as the lectin pathway. The research group in Aarhus, which also includes the laboratory technicians Lisbeth Jensen and Annette G. Hansen, has been central in the elucidation of the lectin pathway through the past 15 years.
The enzyme MASP-1 is able to efficiently auto-activate, for example when it "senses" a bacterium. It then activates MASP-2, which in turn activates the rest of the complement system in a cascade-like manner, where a long list of enzymes sequentially activate each other - much like dominoes. The result is a signal to immune cells to home to the area in the body, where the system is activated, and to kill the intruding bacteria. The bacteria are also covered in "molecular tags", making it easier for the immune cells to recognize and efficiently engulf them. Finally, the complement system directly "punches holes" in the bacteria, by forming pore-like structures in their membranes.
This work has been supported by the Lundbeck Foundation, The Novo Nordic Foundation, as well as the Danish Council for Independent Research - Medical Sciences. Soeren Egedal Degn is employed at the Department of Biomedicine, Aarhus University, through a postdoctoral fellowship from the Carlsberg Foundation.
More articles from Life Sciences:
In Early Earth, Iron Helped RNA Catalyze Electron Transfer
21.05.2013 | Georgia Institute of Technology, Research Communications
Resistance to last-line antibiotic makes bacteria resistant to immune system
21.05.2013 | American Society for Microbiology
University of Würzburg physicists have succeeded in creating a new type of laser.
Its operation principle is completely different from conventional devices, which opens up the possibility of a significantly reduced energy input requirement. The researchers report their work in the current issue of Nature.
It also emits light the waves of which are in phase with one another: the polariton laser, developed ...
Innsbruck physicists led by Rainer Blatt and Peter Zoller experimentally gained a deep insight into the nature of quantum mechanical phase transitions.
They are the first scientists that simulated the competition between two rival dynamical processes at a novel type of transition between two quantum mechanical orders. They have published the results of their work in the journal Nature Physics.
“When water boils, its molecules are released as vapor. We call this ...
Researchers have shown that, by using global positioning systems (GPS) to measure ground deformation caused by a large underwater earthquake, they can provide accurate warning of the resulting tsunami in just a few minutes after the earthquake onset.
For the devastating Japan 2011 event, the team reveals that the analysis of the GPS data and issue of a detailed tsunami alert would have taken no more than three minutes. The results are published on 17 May in Natural Hazards and Earth System Sciences, an open access journal of ...
A new study of glaciers worldwide using observations from two NASA satellites has helped resolve differences in estimates of how fast glaciers are disappearing and contributing to sea level rise.
The new research found glaciers outside of the Greenland and Antarctic ice sheets, repositories of 1 percent of all land ice, lost an average of 571 trillion pounds (259 trillion kilograms) of mass every year during the six-year study period, making the oceans rise 0.03 inches (0.7 mm) per year. ...
About 99% of the world’s land ice is stored in the huge ice sheets of Antarctica and Greenland, while only 1% is contained in glaciers.
However, the meltwater of glaciers contributed almost as much to the rise in sea level in the period 2003 to 2009 as the two ice sheets: about one third. This is one of the results of an international study with the involvement of geographers from the University of Zurich.
21.05.2013 | Studies and Analyses
21.05.2013 | Life Sciences
21.05.2013 | Studies and Analyses
17.05.2013 | Event News
15.05.2013 | Event News
08.05.2013 | Event News