Featured Research

from universities, journals, and other organizations

Blocking Effects Of Viral Infections May Prevent Asthma In Young Children

Date:
November 9, 2007
Source:
Washington University in St. Louis
Summary:
Babies who get severe respiratory viral infections are much more likely to suffer from asthma as they get older. Now researchers have pinpointed a key step in the development of asthma in mice after a severe respiratory infection. They suggest that medications designed to interfere with this mechanism could potentially prevent many cases of childhood asthma.

Babies who get severe respiratory viral infections are much more likely to suffer from asthma as they get older. Now researchers at Washington University School of Medicine in St. Louis have pinpointed a key step in the development of asthma in mice after a severe respiratory infection. They suggest that medications designed to interfere with this mechanism could potentially prevent many cases of childhood asthma.

"A severe respiratory infection in infancy greatly increases the risk of developing asthma," says the study's lead author Mitchell Grayson, M.D., assistant professor of medicine in the Division of Allergy and Immunology. "Less than one in 30 people who don't suffer a severe respiratory infection as a baby develop asthma, but of those who do get these infections, one in five goes on to have asthma."

Grayson and colleagues recently published their research in the Journal of Experimental Medicine. They found that mice that developed asthma-like symptoms after a severe respiratory viral infection had an unusual immune reaction. During the infection, the mice produced antibodies and immune signals similar to those produced during an allergic response, instead of those typically made in response to infection. That started a chain reaction that led to asthma. The researchers propose that a similar reaction occurs in some people who suffer severe respiratory viral infections.

"We think genetically predisposed individuals will tend to have this kind of immune reaction to a severe respiratory viral infection," Grayson says. "In those people an allergic-type response could be part of their antiviral immune response. That sets them up to make antibodies against a lot of environmental substances, like pet dander or pollen, and they can go on to develop allergies or asthma."

Reports by the Centers for Disease Control and Prevention indicate that the number of people with asthma in the United States rose from approximately 7 million in 1980 to about 20 million in 2003. The reasons for this trend are unclear, Grayson indicates. But he suggests that a growing population density and the resulting increase in transmission of respiratory viral infections might be a cause.

Respiratory syncytial virus (RSV) is a common source of respiratory infections. In the United States nearly all children have been infected with RSV by two or three years of age. Severe RSV infections, typified by persistent coughing, wheezing and gasping for breath, send many thousands of children to the hospital each year.

To investigate the connection between severe respiratory viral infections and subsequent asthma, the researchers used mice genetically selected to have an asthma susceptibility and infected them with a virus similar to RSV. They found that severe respiratory infections in the mice induced an allergic-type immune response and ultimately caused long-term changes in the airways of the lungs that are hallmarks of chronic asthma.

The researchers discovered that certain immune cells in the mouse lungs reacted to severe viral infections by releasing compounds that instigated an inflammatory response. That in turn induced many lung airway cells to transform into mucus-producing cells, which can cause the obstruction of lung passages and shortness of breath characteristic of asthma.

The researchers found that interfering with this process by altering the immune cells or removing the inflammatory compounds they secreted prevented overgrowth of mucus-producing cells.

The findings promise a new approach to asthma prevention, according to Grayson. "This offers a different way of thinking about what happens in the development of asthma," Grayson says. "It may be possible to prevent many cases of asthma and other chronic inflammatory airway diseases by stopping allergic-type antibody production after a severe viral infection in infants."

Journal reference: Grayson MH, Cheung D, Rohlfing MM, Kitchens R, Spiegel DE, Tucker J, Battaile JT, Alevy Y, Yan L, Agapov E, Kim EY, Holtzman MJ. Induction of high-affinity IgE receptor on lung dendritic cells during viral infection leads to mucous cell metaplasia. Journal of Experimental Medicine 2007 Oct 29;204(11):2759-69.

Funding from the National Institute of Allergy and Infectious Disease, the National Heart, Lung and Blood Institute, Genentech Inc., Novartis International AG, the Martin Schaeffer Fund and the Alan A. and Edith L. Wolff Charitable Trust supported this research.


Story Source:

The above story is based on materials provided by Washington University in St. Louis. Note: Materials may be edited for content and length.


Cite This Page:

Washington University in St. Louis. "Blocking Effects Of Viral Infections May Prevent Asthma In Young Children." ScienceDaily. ScienceDaily, 9 November 2007. <www.sciencedaily.com/releases/2007/11/071107160135.htm>.
Washington University in St. Louis. (2007, November 9). Blocking Effects Of Viral Infections May Prevent Asthma In Young Children. ScienceDaily. Retrieved August 27, 2014 from www.sciencedaily.com/releases/2007/11/071107160135.htm
Washington University in St. Louis. "Blocking Effects Of Viral Infections May Prevent Asthma In Young Children." ScienceDaily. www.sciencedaily.com/releases/2007/11/071107160135.htm (accessed August 27, 2014).

Share This




More Health & Medicine News

Wednesday, August 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Predicting Heart Transplant Rejection With a Blood Test

Predicting Heart Transplant Rejection With a Blood Test

Ivanhoe (Aug. 27, 2014) Now a new approach to rejection of donor organs could change the way doctors predict transplant rejection…without expensive, invasive procedures. Video provided by Ivanhoe
Powered by NewsLook.com
Better Braces That Vibrate

Better Braces That Vibrate

Ivanhoe (Aug. 27, 2014) The length of time you have to keep your braces on could be cut in half thanks to a new device that speeds up the process. Video provided by Ivanhoe
Powered by NewsLook.com
Smartphone App Tracks Your Heart Rate

Smartphone App Tracks Your Heart Rate

Ivanhoe (Aug. 27, 2014) A new app that can track your heart rate 24/7 is available for download in your app store and its convenience could save your life. Video provided by Ivanhoe
Powered by NewsLook.com
Stroke in Young Adults

Stroke in Young Adults

Ivanhoe (Aug. 27, 2014) A stroke can happen at any time and affect anyone regardless of age. This mother chose to give her son independence and continue to live a normal life after he had a stroke at 18 years old. Video provided by Ivanhoe
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