Featured Research

from universities, journals, and other organizations

How Allergic Reactions Are Triggered

Date:
January 17, 2008
Source:
Beth Israel Deaconess Medical Center
Summary:
In demonstrating that a group of calcium ion channels play a crucial role in triggering inflammatory responses, researchers have not only solved a longstanding molecular mystery regarding the onset of asthma and allergy symptoms, but have also provided a fundamental discovery regarding the functioning of mast cells.

In demonstrating that a group of calcium ion channels play a crucial role in triggering inflammatory responses, researchers at Beth Israel Deaconess Medical Center (BIDMC) have not only solved a longstanding molecular mystery regarding the onset of asthma and allergy symptoms, but have also provided a fundamental discovery regarding the functioning of mast cells.

A group of immune cells found in tissues throughout the body, mast cells were once exclusively known for their role in allergic reactions, according to the study's lead author Monika Vig, PhD, an investigator in the Department of Pathology at BIDMC and Instructor of Medicine at Harvard Medical School. "Mast cells store inflammatory cytokines and compounds [including histamine and heparin] in sacs called granules," she explains. "When the mast cells encounter an allergen -- pollen, for example -- they 'degranuate,' releasing their contents and triggering allergic reactions."

But, she adds, in recent years, scientists have uncovered numerous other roles for mast cells, suggesting they are key to a number of biological processes and are involved in diseases ranging from multiple sclerosis and rheumatoid arthritis to cancer and atherosclerosis.

In order for mast cells to function, they require a biological signal -- specifically, calcium. Calcium moves in and out of the cells by way of ion channels known as CRAC (calcium-release-activated calcium) currents. Last year, several research groups, including Vig's, identified CRACM1 as being the exact gene that was encoding for this calcium channel.

"With the identification of this long-elusive gene, we were able to create a knockout mouse that lacked CRACM1, and [as predicted] these animals proved to be resistant to various stimuli that usually cause severe allergic reactions," she explains. Further experiments demonstrated that mast cells removed from the CRACM1 knockouts were not able to take in calcium, and therefore, were unable to provoke allergic responses when they were exposed to allergens.

"These findings provide the genetic demonstration that CRAC channels are essential in mast-cell activation," notes senior author Jean-Pierre Kinet, MD, BIDMC Professor of Pathology at Harvard Medical School. "This provides the proof of concept that an inhibitor of the CRAC channel should be able to impact mast-cell related diseases, including asthma and allergic diseases."

Adds Vig, "Since mast cells are also known to contribute to the progression of several other debilitating diseases, including multiple sclerosis, rheumatoid arthritis and cancer, an inhibitor of the CRAC channel could, in the future, help in slowing the progression of these diseases as well as alleviate disease symptoms."

These findings appear in the January 2008 issue of Nature Immunology. In addition to Vig and Kinet, study coauthors include BIDMC investigators James Billingsley, Huiyun Wang and Marie-Helene Jouvin; Wayne DeHaven, Gary Bird and James Putney of the National Institute of Environmental Health Sciences; and Patricia Rao and Amy Hutchings of Synta Pharmaceuticals, Lexington, Mass.

This study was funded by grants from the National Institutes of Health, the Irvington Institute and the intramural program of the National Institutes of Health, National Institute of Environmental Health Sciences.


Story Source:

The above story is based on materials provided by Beth Israel Deaconess Medical Center. Note: Materials may be edited for content and length.


Cite This Page:

Beth Israel Deaconess Medical Center. "How Allergic Reactions Are Triggered." ScienceDaily. ScienceDaily, 17 January 2008. <www.sciencedaily.com/releases/2008/01/080114101833.htm>.
Beth Israel Deaconess Medical Center. (2008, January 17). How Allergic Reactions Are Triggered. ScienceDaily. Retrieved April 19, 2014 from www.sciencedaily.com/releases/2008/01/080114101833.htm
Beth Israel Deaconess Medical Center. "How Allergic Reactions Are Triggered." ScienceDaily. www.sciencedaily.com/releases/2008/01/080114101833.htm (accessed April 19, 2014).

Share This



More Health & Medicine News

Saturday, April 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

'Holy Grail' Of Weight Loss? New Find Could Be It

'Holy Grail' Of Weight Loss? New Find Could Be It

Newsy (Apr. 18, 2014) In a potential breakthrough for future obesity treatments, scientists have used MRI scans to pinpoint brown fat in a living adult for the first time. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. Video provided by Newsy
Powered by NewsLook.com
Obama: 8 Million Healthcare Signups

Obama: 8 Million Healthcare Signups

AP (Apr. 17, 2014) President Barack Obama gave a briefing Thursday announcing 8 million people have signed up under the Affordable Care Act. He blasted continued Republican efforts to repeal the law. (April 17) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins