Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UCLA study uncovers clues for why Graves' disease attacks the eyes

02.03.2007
Discovery suggests new target for treating the autoimmune disorder

UCLA researchers have uncovered new clues that may explain why Graves’ disease (GD) attacks the muscle tissue behind the eyes, often causing them to bulge painfully from their sockets, as in the late actor Marty Feldman.

Scientists at UCLA’s Jules Stein Eye Institute and Harbor-UCLA Medical Center discovered defects in the infection-fighting T-cells of GD patients’ immune systems. Reported March 1 in the Journal of Immunology, their study may deepen understanding of how the autoimmune disorder damages the body and offer a new target for treating the disfiguring disease.

Earlier research found that GD patients’ immune systems produce an antibody that other people do not. Not recognizing the patient’s thyroid as "self," the antibody mistakenly mounts an attack against the organ, causing inflammation and damage to the body, including eye tissue.

... more about:
»T-cell »UCLA »patients’ »receptor

In the current study, UCLA researchers discovered that T-cells taken from GD patients contain an abnormal surplus of the receptor targeted by this antibody. An antibody must latch to a specific receptor – like a key into a lock -- in order to elicit a cellular response. The receptors mobbed the patients’ immune systems, even on T-cells that normally would not produce them.

"We didn’t know why GD patients’ cells created a new antibody, but had a hunch that that it sprang from an immune abnormality," explained Dr. Raymond Douglas, first author and assistant professor of ophthalmology at the Jules Stein Eye Institute. "Because T-cells are the generals of the immune system and lead the attack in any immune response, we assumed that they played a key role in this antibody’s development."

The team tested GD patients’ blood for the antibody and compared their findings to samples from healthy people, with about 100 subjects in each group. The new antibody was found in almost all of the GD patients’ blood.

The new antibody binds to the excess receptors on the T-cells, mimicking the actions of a hormone called IGF-1, or insulin-like growth factor 1. Similar to insulin, IGF-1 stimulates cell growth while suppressing normal cell death. The team suspects that this mechanism prolongs the survival of older T-cells, causing a cascade of autoimmune problems that spur the body to attack its own tissue.

"We think that the extra receptors allow the new antibody and IGF-1 to disrupt the programming of the T-cells," said principal investigator Dr. Terry Smith, professor of medicine at the David Geffen School of Medicine and chief of molecular medicine at Harbor-UCLA Medical Center.

"The antibody provokes the receptor to signal the T-cell to grow and multiply – long after the cell was programmed to die," he explained. "After two or three generations of this process, we suspect that the high-jacked T-cells mutiny over the normal T-cells, sparking the body’s immune reaction against itself."

The next step is to identify what the T-cells are reacting to and how the receptor enables the cells to survive beyond their normal lifespan. The team plans to develop an antibody drug to block the receptor from interacting with the T-cells and slow down the disease.

In Graves’ disease, the thyroid gland goes into overdrive, producing excess levels of hormone that attack the tissue behind the eye, causing them to protrude. In extreme cases, patients experience trouble closing their eyelids, severe double vision, corneal scarring, optic nerve damage and even blindness.

Graves’ disease is nine times more common in women than men. The disorder most often strikes during the childbearing years, and runs an average course of one to two years. No cure exists, though surgery can be done at the end stage to correct disfigurement.

Enrique Rivero | EurekAlert!
Further information:
http://www.mednet.ucla.edu

Further reports about: T-cell UCLA patients’ receptor

More articles from Life Sciences:

nachricht Seeing on the Quick: New Insights into Active Vision in the Brain
15.08.2018 | Eberhard Karls Universität Tübingen

nachricht New Approach to Treating Chronic Itch
15.08.2018 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

Unraveling the nature of 'whistlers' from space in the lab

15.08.2018 | Physics and Astronomy

Diving robots find Antarctic winter seas exhale surprising amounts of carbon dioxide

15.08.2018 | Earth Sciences

Early opaque universe linked to galaxy scarcity

15.08.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>