Navigation Links
GARP makes the difference
Date:6/15/2009

Scientists from the Helmholtz Center for Infection Research in Braunschweig, Germany and the Medical School Hannover, Germany have succeeded in treating immune cells in a way that enables them to inhibit unwanted immune reactions such as organ rejection. Their results have now been published in the current issue of the scientific journal Journal of Cellular and Molecular Medicine.

The immune system keeps us healthy: day and night it protects us against invading and harmful pathogens. But this fulltime surveillance can also turn into a problem, for example after an organ transplant. The immune system recognizes the new organ as "foreign" and starts fighting it. In the end, the life-saving transplant will be rejected. Until now, only special drugs have managed to keep the immune system silent and thus inhibit organ rejection.

Theoretically, these drugs are not necessary because the immune system has its own unique "peace makers": regulatory T cells (Tregs), a special group of helper T cells, an important cell type of the immune system. Tregs inhibit immune reactions and are thus of special medical interest. Until now, distinguishing between Tregs and helper T cells has represented a problem for scientists. Now, in co-operation with the Medical School Hannover, researchers from the Helmholtz Centre for Infection Research in Braunschweig have identified a molecular factor that plays an essential role in Treg function. This protein constitutes the key difference between Tregs and helper T cells. Furthermore, the scientists have also generated Tregs from helper T cells that permanently maintained their characteristics.

The key to Tregs is called "GARP". Michael Probst-Kepper is a researcher in a junior research group that is financed by the German Volkswagen foundation, he works at both HZI and MHH. He has now deciphered the special role of the GARP protein. Until now, scientists had only little distinguishing features to aid them in separating T cells that trigger a transplant rejection from those that inhibit such a reaction: they mainly looked at molecular features that both cell types have the one more, the other less. "It's like looking at two cars that appear to be the same. Except that one is capable of driving while the other doesn't drive anymore. But you cannot see that from the outside," says Michael Probst-Kepper. He deciphered the role of GARP: this new-found factor only exists in Tregs and initiates a complex network of various molecules. "If you don't want a car to drive anymore, you pull the key out and cut the petrol pipe. GARP does the same: it prevents Tregs from stepping on the gas."

The scientist artificially inserted GARP into those T cells that start an immune reaction against transplants. The result was a substantial advance for medicine: the transplant-rejecting T cells developed permanently into Tregs those cells that inhibit the activation of aggressive T cells and thus prevent organ rejection. Furthermore, the researchers also furnished the counter evidence: Michael Probst-Kepper muted the GARP gene in Tregs. As a result, the Tregs lost their "peace making" characteristics. "The cells could start driving again," he says. "With this study we were able to show the complexity of the Treg system for the first time, developing a powerful tool for medicine to develop new therapies and drugs."


'/>"/>

Contact: Dr. Bastian Dornbach
bastian.dornbach@helmholtz-hzi.de
49-531-618-11407
Helmholtz Association of German Research Centres
Source:Eurekalert

Related biology news :

1. New drug makes weight loss safer
2. How mother of thousands makes plantlets
3. For honey bee queens, multiple mating makes a difference
4. Scientists spy enzyme that makes us unique
5. Thinking makes it so: Science extends reach of prosthetic arms
6. Choosing dry or wet food for cats makes little difference
7. Technique controls nanoparticle size, makes large numbers
8. Decoy makes sitting duck of superbugs
9. Case researcher in RNA biology makes waves by challenging current thinking
10. New process makes nanofibers in complex shapes and unlimited lengths
11. Diabetes makes it hard for blood vessels to relax
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:7/20/2017)... 20, 2017 Delta (NYSE: DAL ) customers now ... aircraft at Reagan Washington National Airport (DCA). ... Delta launches biometrics to board aircraft at ... Delta,s biometric boarding pass experience ... is now integrated into the boarding process to allow eligible Delta SkyMiles ...
(Date:6/14/2017)...  IBM (NYSE: IBM ) is introducing several innovative ... to developing collaboration between startups and global businesses, taking place ... the event, nine startups will showcase the solutions they have ... France is one ... a 30 percent increase in the number of startups created ...
(Date:5/16/2017)... DALLAS , May 16, 2017   ... for health organizations, and MD EMR Systems ... certified development partner for GE, have established a ... Patient Portal product and the GE Centricity™ products, ... Centricity EMR. These new integrations ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... , ... October 11, 2017 , ... ... (FDA) has granted orphan drug designation to SBT-100, its novel anti-STAT3 (Signal Transducer ... treatment of osteosarcoma. SBT-100 is able to cross the cell membrane and bind ...
(Date:10/10/2017)... Angeles, CA (PRWEB) , ... ... ... Inc., a development-stage cancer-focused pharmaceutical company advancing targeted antibody-drug conjugate (ADC) therapeutics, ... uses of targeted HPLN (Hybrid Polymerized Liposomal Nanoparticle), a technology developed in ...
(Date:10/10/2017)... ... October 10, 2017 , ... Dr. Bob Harman, founder ... local San Diego Rotary Club. The event entitled “Stem Cells and ... had 300+ attendees. Dr. Harman, DVM, MPVM was joined by two human doctors: ...
(Date:10/10/2017)... 2017 SomaGenics announced the receipt of a ... RealSeq®-SC (Single Cell), expected to be the first commercially ... microRNAs) from single cells using NGS methods. The NIH,s ... accelerate development of approaches to analyze the heterogeneity of ... techniques for measuring levels of mRNAs in individual cells ...
Breaking Biology Technology: