Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Potential new way of treating inflammatory diseases identified

17.09.2007
Scientists have shown for the first time that platelets, the cells needed for blood clotting, help white blood cells called neutrophils fight inflammation.

The discovery was made by Ralph Kettritz, Professor of Medicine at the Medical Faculty of the Charite and investigator at the Max Delbrueck Center for Molecular Medicine, Berlin, Germany, and colleagues. The results of the study could lead to new anti-inflammatory compounds for the treatment of inflammatory vascular injury.

“We found an entirely new mechanism by which neutrophils induce inflammation,” Kettritz says. “So far, scientists have shown that platelets form clots and neutrophils can cause symptoms of inflammation, such as swelling, redness, and heat. In this study, we show that platelets and neutrophils sometimes work together to heal a wound or fight an infection.”

The new study, to be published in the September 21 issue of the Journal of Biological Chemistry, was selected as a “Paper of the Week” by the journal’s editors, meaning that it belongs to the top one percent of papers reviewed in significance and overall importance.

During inflammation – a protective reaction from the tissues following a wound or infection – white blood cells attack bacteria and platelets form clots that close any potential wound. White blood cells called neutrophils are the first to launch an attack against the bacteria. They are attracted by substances, such as granulocyte-macrophage colony-stimulating factor (GM-CSF), that are released at the early stages of inflammation. Once activated, neutrophils engulf and destroy bacteria and damaged tissue.

In addition to neutrophils, two other types of white blood cells, called macrophages and lymphocytes, also engage in the fight against bacteria. These cells are activated by a chemical compound called tumor necrosis factor (TNF) released by the neutrophils. Although there are several ways by which neutrophils release TNF, Kettritz and colleagues found that neutrophils can be stimulated to produce TNF in a totally new and different way.

“Usually, TNF is produced when specific chemicals bind to proteins called receptors on the surface of a neutrophil, which tells the cell that it should make TNF,” Kettritz says. “This time, we found that a neutrophil can acquire receptors that are not already present on its surface and use them to stimulate the production of TNF.”

The receptors, called GPIIb/IIIa, are sent to neutrophils by platelets. Like a letter sent in an envelope, these receptors are packaged in vesicles called microparticles that, when they reach a neutrophil, bind to its surface and release the receptors. Once released, the receptors are incorporated into the neutrophil’s cell membrane.

Kettritz and his team also found that these newly-acquired receptors did not work alone. To stimulate neutrophils to produce TNF, the GPIIb/IIIa receptor works in tandem with the receptor for GM-CSF (the substance produced during the early stages of inflammation). The scientists found that the neutrophil produces TNF both when GPIIb/IIIa binds to a protein outside the cell called fibronectin and when the GM-CSF receptor binds to GM-CSF.

“We have shown for the first time that platelets can, by using microparticles, help other cells – in this case, neutrophils – respond to inflammation,” Kettritz says. “We also found for the first time that receptors involved in blood clotting also trigger an inflammatory response.”

These results may help devise new drugs against several types of inflammation by targeting the GPIIb/IIIa receptors acquired by neutrophils. In particular, drugs currently used to prevent blood clotting by inhibiting GPIIb/IIIa receptors on platelets may be used against inflammation.

Kettritz and colleagues tested three of these drugs – abciximab, epifibatide, and tirofiban – on cell cultures in which neutrophils had received the GPIIb/IIIa receptors from platelets and confirmed the drugs’ effects on inflammation. The scientists showed that all three drugs inhibited the production of TNF, which reduced inflammation in these cells. These results also led the researchers to speculate that some of the beneficial effects of the three drugs on patients with acute coronary syndrome result from their anti-inflammatory properties.

If the drugs’ effects are confirmed in clinical trials, they could be used against several types of inflammation that include acute vasculitis, an inflammation of blood vessels that can affect any organ in the body. Also, the drugs have been used successfully to treat acute coronary syndrome, which refers to certain types of heart attack and unstable angina. The new results show that these beneficial effects may be due not only to their anti-clotting properties, but also to their anti-inflammatory qualities.

“The results of this study are very encouraging,” Kettritz says. “Although specific drugs that target GPIIb/IIIa receptor actions on neutrophils may need to be developed in the future, these three drugs can now be tested in clinical trials, which could make them – or modified versions of them – new anti-inflammatory drugs.”

Pat Pages | EurekAlert!
Further information:
http://www.asbmb.org

Further reports about: GM-CSF GPIIb/IIIa Kettritz Neutrophil Platelets anti-inflammatory inflammation inflammatory types

More articles from Life Sciences:

nachricht The balancing act: An enzyme that links endocytosis to membrane recycling
07.12.2016 | National Centre for Biological Sciences

nachricht Transforming plant cells from generalists to specialists
07.12.2016 | Duke University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>