The discovery of a crucial mechanism that controls the activation of T cells, a blood cell whose primary job is to fight infection in the body, may enable the development of new drugs to treat autoimmune disease, transplant rejection, and similar disorders in which T cells play a major role. The finding, "T Cell Receptor Signals to NF-kB Are Transmitted by a Cytosolic p62-Bcl10-Malt1-IKK Signalosome," was published in the May 13 issue of Science Signaling.
A team of Uniformed Services University of the Health Sciences (USU) researchers led by Dr. Brian Schaefer, Associate Professor in USU’s Department of Microbiology and Immunology, has demonstrated that the “POLKADOTS signalosome” (named for its dot-like appearance in cells) activates a protein called “NF-kappaB” in T cells. A signalosome is a cluster of proteins that works together inside a cell to control the activity of other proteins. NF-kappaB is a protein that turns on many different T cell functions, including those that contribute to autoimmunity and rejection of transplants.
Dr. Schaefer’s team, including lead author, Dr. Suman Paul, had previously shown that the POLKADOTS signalosome, in addition to activating this protein, also limits how much NF-kappaB is turned on. Because the POLKADOTS signalosome is a major point of control for NF-kappaB activation, it may be an attractive target for the design of new drugs to block or regulate T cell functions.
Normally, T cells play a key role in maintaining health, by helping to eliminate invading disease-causing bacteria and viruses. However, in some individuals, T cells begin to react against tissues in the body, causing autoimmunity. Also, when a patient receives an organ transplant, T cells will react to that organ and cause transplant rejection, if T cell functions are not successfully blocked. There are currently only a small number of drugs available to treat autoimmunity and transplant rejection, and these drugs do not work for all patients.
Inhibiting NF-kappaB activation has long been recognized as a potentially useful strategy for blocking the T cell responses that cause autoimmunity and transplant rejection. However, because NF-kappaB is necessary for a wide variety of important processes throughout the body, directly targeting this protein would lead to many undesired and harmful side effects. Importantly, Dr. Schaefer’s group predicts that drugs that block the activity of the POLKADOTS signalosome would inhibit NF-kappaB only in T cells. This is because the POLKADOTS signalosome appears to be present only in T cells. If successfully produced, drugs that act on the POLKADOTS signalosome may be a powerful new therapy for the treatment of many different autoimmune diseases and transplant rejection.
This work was supported by grants from the U.S. NIH (Al057481), the Center for Neuroscience and Regenerative Medicine, and pre-doctoral fellowships from the American Heart Association (10PRE3150039) and the Henry M. Jackson Foundation for the Advancement of Military Medicine.
The Uniformed Services University of the Health Sciences, founded by an act of Congress in 1972, is the nation’s federal health sciences university and the academic heart of the Military Health System. USU students are primarily active duty uniformed officers in the Army, Navy, Air Force and Public Health Service who receive specialized education in tropical and infectious diseases, TBI and PTSD, disaster response and humanitarian assistance, global health, and acute trauma care. A large percentage of the university’s more than 5,000 physician and nearly 730 advanced practice nursing alumni are supporting operations around the world, offering their leadership and expertise. USU also has graduate programs in biomedical sciences and public health committed to excellence in research, and in oral biology. The University's research program covers a wide range of clinical and other topics important to both the military and public health. For more information about USU and its programs, visit www.usuhs.edu.
Sharon Willis | newswise
27.03.2015 | Oak Ridge National Laboratory
How did the chicken cross the sea?
27.03.2015 | Michigan State University
In an experiment at the Department of Energy's SLAC National Accelerator Laboratory, scientists precisely measured the temperature and structure of aluminum as...
The IPH presents a solution at HANNOVER MESSE 2015 to make ship traffic more reliable while decreasing the maintenance costs at the same time. In cooperation with project partners, the research institute from Hannover, Germany, has developed a sensor system which continuously monitors the condition of the marine gearbox, thus preventing breakdowns. Special feature: the monitoring system works wirelessly and energy-autonomously. The required electrical power is generated where it is needed – directly at the sensor.
As well as cars need to be certified regularly (in Germany by the TÜV – Technical Inspection Association), ships need to be inspected – if the powertrain stops...
When an earthquake hits, the faster first responders can get to an impacted area, the more likely infrastructure--and lives--can be saved.
The Atlantic overturning is one of Earth’s most important heat transport systems, pumping warm water northwards and cold water southwards. Also known as the Gulf Stream system, it is responsible for the mild climate in northwestern Europe.
Scientists now found evidence for a slowdown of the overturning – multiple lines of observation suggest that in recent decades, the current system has been...
Because they are regularly subjected to heavy vehicle traffic, emissions, moisture and salt, above- and underground parking garages, as well as bridges, frequently experience large areas of corrosion. Most inspection systems to date have only been capable of inspecting smaller surface areas.
From April 13 to April 17 at the Hannover Messe (hall 2, exhibit booth C16), engineers from the Fraunhofer Institute for Nondestructive Testing IZFP will be...
25.03.2015 | Event News
19.03.2015 | Event News
17.03.2015 | Event News
27.03.2015 | Agricultural and Forestry Science
27.03.2015 | Materials Sciences
27.03.2015 | Ecology, The Environment and Conservation