Navigation Links
Gene for immune deficiency syndromes found

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 ce lls 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.


'"/>

Source:Children's Hospital Boston


Related biology news :

1. Fox Chase Cancer Center scientists identify immune-system mutation
2. Genetically modified natural killer immune cells attack, kill leukemia cells
3. Studies reveal methods viruses use to sidestep immune system
4. Jumping gene helps explain immune systems abilities
5. Scientists solve structure of key protein in innate immune response
6. Rats infected as newborns grew up vulnerable to memory problems during an immune challenge
7. NYU study reveals how brains immune system fights viral encephalitis
8. Chemists identify immune system mechanism for methamphetamine binges
9. Multi-purpose protein regulates new protein synthesis and immune cell development
10. Genetic defects give the immune system the green light to attack the pancreas
11. Leprosy microbes lead scientists to immune discovery
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/2/2016)... The Department of Transport Management (DOTM) ... million US Dollar project, for the , Supply ... Enrolment, and IT Infrastructure , to ... implementation of Identity Management Solutions. Numerous renowned international vendors participated ... was selected for the most compliant and innovative ...
(Date:5/24/2016)... IRVINE, Calif. , May 24, 2016 Ampronix facilitates superior patient care ... LMD3251MT  3D medical LCD display is the latest premium product recently added to ... ... ... Sony 3d Imaging- LCD Medical Display- Ampronix News ...
(Date:5/9/2016)... Elevay is currently known as ... for high net worth professionals seeking travel for work ... world, there is still no substitute for a face-to-face ... your deal with a firm handshake. This is why ... of citizenship via investment programs like those offered by ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... CLEVELAND , June 27, 2016  Global ... average 4.6 percent through 2020 to $7.2 billion.  ... (food and beverages, cleaning products, biofuel production, animal ... and biotechnology, diagnostics, and biocatalysts). Food and beverages ... gains driven by increasing consumption of products containing ...
(Date:6/27/2016)... ... June 27, 2016 , ... Newly ... technologies, services and solutions to the healthcare market. The company's primary focus is ... manufacturing, sales and marketing strategies that are necessary to help companies efficiently bring ...
(Date:6/24/2016)... 2016 Epic Sciences unveiled a liquid ... to PARP inhibitors by targeting homologous recombination deficiency ... new test has already been incorporated into numerous ... types. Over 230 clinical trials are ... including PARP, ATM, ATR, DNA-PK and WEE-1. Drugs ...
(Date:6/23/2016)... CAMBRIDGE, Mass. , June 23, 2016 /PRNewswire/ ... the development of novel compounds designed to target ... compound, napabucasin, has been granted Orphan Drug Designation ... in the treatment of gastric cancer, including gastroesophageal ... cancer stemness inhibitor designed to inhibit cancer stemness ...
Breaking Biology Technology: