Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Gene for immune deficiency syndromes found

12.07.2005


Finding may yield a new test to explain recurring infections



A newly discovered gene mutation may account for many cases of immune deficiency, in particular two syndromes known as immunoglobulin A (IgA) deficiency and Common Variable Immunodeficiency (CVID), report researchers in the July issue of Nature Genetics. The discovery may lead to a new diagnostic test for these conditions, which make people highly susceptible to infections and often go unrecognized because of a lack of good tests.

IgA deficiency affects 1 in 600 people; CVID is less common but more severe. Children and adults with either condition suffer relentlessly recurring ear infections, sinus infections, bronchitis, pneumonias and gastrointestinal infections. IgA deficiency and CVID can occur in the same family, and also predispose people to autoimmunity, particularly affecting the thyroid gland and resulting in thyroid hormone insufficiency. Finally, people with CVID are susceptible to B-cell lymphomas.


The researchers, led by Raif Geha, MD, and Emanuela Castigli, PhD, in the Division of Immunology at Children’s Hospital Boston, found mutations in a gene known as TACI in 4 of 19 unrelated patients with CVID and in 1 of 16 unrelated patients with IgA deficiency. None of 50 healthy people tested had a TACI mutation. Four of the 5 patients with TACI mutations were studied further, and all 4 had relatives with the same mutations. Eleven of the 12 identified relatives with TACI or IgA deficiency reported a history of recurrent infections and were found to have low levels of immunoglobulin A (IgA), immunoglobulin G (IgG) or both.

TACI mutations interfere with two aspects of the immune response that involve maturation of B cells, the white blood cells that make immunoglobulins, which function as antibodies, to fight infections. Normally, TACI triggers B cells to switch from making immunoglobulin M (IgM), an antibody produced early in the body’s immune response, to making other immunoglobulins like IgA and IgG. More important, TACI signals B cells to produce antibodies with a high affinity for specific attackers. Because TACI mutations are dominant, people with even one copy of the mutation will be unable to mount a strong antibody response.

"A test for TACI would allow for diagnosis of more children and their relatives," says Geha, senior author of the study and a professor of pediatrics at Harvard Medical School. "Many children who are sick are now missed, because they can have normal IgA and IgG levels, yet they still have poor antibody responses and get the same bacteria and viruses again and again."

The gene discovery will immediately not change therapy, Geha adds. "For the time being, it’s prophylactic antibiotics or IV immunoglobulin infusions every three weeks," he says.

Geha’s team previously demonstrated that TACI binds to two other proteins made by cells in the respiratory and gastrointestinal lining, known as APRIL and BAFF, to trigger the signal for B cells to mature. Geha believes that additional cases of immune deficiency result from mutations in the APRIL and BAFF genes, and plans to verify this in further studies.

Aaron Patnode | EurekAlert!
Further information:
http://www.childrens.harvard.edu
http://www.childrenshospital.org/research

More articles from Life Sciences:

nachricht 'Y' a protein unicorn might matter in glaucoma
23.10.2017 | Georgia Institute of Technology

nachricht Microfluidics probe 'cholesterol' of the oil industry
23.10.2017 | Rice 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: Salmonella as a tumour medication

HZI researchers developed a bacterial strain that can be used in cancer therapy

Salmonellae are dangerous pathogens that enter the body via contaminated food and can cause severe infections. But these bacteria are also known to target...

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Symposium on Driving Simulation

23.10.2017 | Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

 
Latest News

Microfluidics probe 'cholesterol' of the oil industry

23.10.2017 | Life Sciences

Gamma rays will reach beyond the limits of light

23.10.2017 | Physics and Astronomy

The end of pneumonia? New vaccine offers hope

23.10.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>