Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The therapeutic antibody eculizumab caught in action

06.06.2016

In collaboration with Alexion Pharmaceuticals, Inc., scientists from Aarhus University have used X-rays to understand how the therapeutic antibody eculizumab prevents our immune system from destroying red blood cells and damaging kidney tissue.

The scientists in Aarhus studied an important protein from the innate immune system called C5 which is cleaved by enzymes when pathogens invade our body as a defense mechanism. The two C5 fragments formed through this cleavage recruit immune cells to fight the pathogen and may directly kill it.


The atomic structure of C5 (blue) bound to the C5-binding part of eculizumab (yellow) shows how eculizumab blocks the cleavage of C5 in blood circulation. This rescues the red blood cells (red disks) from disruption. In real life the proteins are 500 times smaller than the red blood cells.

Credit: Janus Asbjørn Schatz-Jakobsen

Our own cells are protected against damage caused by cleavage of the C5 protein. But in two rare diseases called paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic uremic syndrome (aHUS), this protection is lost due to mutations in our DNA. Patients suffer as their red blood cells and cells in the kidney are continuously damaged, and the diseases are life-threatening.

The global biopharmaceutical company Alexion, headquartered in the U.S., has developed a therapeutic antibody called eculizumab that prevents the cleavage of C5 and thereby treats the two diseases.

The research was performed by PhD student Janus Asbjørn Schatz-Jakobsen and Professor Gregers Rom Andersen at the Department of Molecular Biology and Genetics at Aarhus University in Denmark in collaboration with scientists at Alexion and is now published in The Journal of Immunology with a figure from the article on the cover of the July issue.

Description of tthe research project

Janus first purified C5 from human blood plasma and then mixed it with a fragment of the eculizumab antibody prepared by Alexion solely for this collaboration. After many attempts, Janus managed to form crystals containing the complex between C5 and the antibody fragment. In the following year, more than 200 crystals were investigated by Janus using very intense X-ray radiation at large international facilities in France.

After a total of 18 months with careful and tedious work, Janus was finally able to describe the atomic structure of C5 bound to the eculizumab fragment. This structure revealed that the antibody creates a physical barrier that prevents the cleaving enzymes from forming contacts with C5.

On the other side of the Atlantic Ocean, scientists at Alexion in parallel performed biochemical experiments in which the function of antibodies carrying mutations in regions responsible for binding to C5 were compared to the normal eculizumab antibody.

Janus Asbjørn Schatz-Jakobsen explains: "When I had finished my atomic model and was awaiting the results from Alexion for comparison, I felt almost like a small child waiting for X-mas eve. When the result arrived by email, I could quickly confirm that there was an excellent agreement between my results and those obtained by the Alexion scientists, which confirmed that my model was correct. It was quite a relief and the results from Alexion also made me discover new exciting aspects of my atomic structure that I had not noticed yet."

The new research has also helped the scientists at Aarhus University to better understand the mechanism by which C5 is cleaved by enzymes in the absence of eculizumab. At Alexion, the atomic structure is now used as a framework to understand in details how their therapeutic antibody works and treats the two diseases.

Read the article published in The Journal of Immunology.

For further information, please contact

Professor Gregers Rom Andersen
gra@mbg.au.dk
mobile: 45-3025-6646

PhD student Janus Asbjørn Schatz-Jakobsen
janusasj@mbg.au.dk
Tel. 45-8715-4201
Department of Molecular Biology and Genetics
Aarhus University, Denmark

http://www.au.dk 

Professor Gregers Rom Andersen | EurekAlert!

More articles from Life Sciences:

nachricht Decoding the genome's cryptic language
27.02.2017 | University of California - San Diego

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Safe glide at total engine failure with ELA-inside

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Cells adapt ultra-rapidly to zero gravity

28.02.2017 | Health and Medicine

An Atom Trap for Water Dating

28.02.2017 | Earth Sciences

New pop-up strategy inspired by cuts, not folds

27.02.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>