Featured Research

from universities, journals, and other organizations

Antibody Therapy Reduces Asthma In Mice

Date:
March 6, 2006
Source:
Journal of Clinical Investigation
Summary:
Asthma rates are rapidly increasing, particularly in children. Although asthma is mediated in part by activation of special immune cells called Th2 cells, the precise causes are unclear. Now scientists report that a small allergy-inducing protein called C5a produced in the lungs can prevent or induce asthma, depending upon the timing of allergen exposure.

Asthma rates are rapidly increasing, particularly in children. Although asthma is mediated in part by activation of special immune cells called Th2 cells, the precise causes are unclear.

Now, in a study appearing in the March issue of the Journal of Clinical Investigation, Jörg Köhl and colleagues from the Cincinnati Children's Hospital Research Foundation report that a small allergy-inducing protein called C5a produced in the lungs can prevent or induce asthma, depending upon the timing of allergen exposure.

The authors blocked the C5a receptor (C5aR) by either giving normal mice an antibody against C5aR, or by genetically deleting C5aR. The researchers then determined the animals' response to inhalation of one of two allergens: egg ovalbumin (OVA), which fails to induce asthma; or house dust mites, which induce asthma-like symptoms relevant to human disease.

The authors found that mice in which C5aR was blocked or deleted prior to exposure to either allergen developed asthma-like symptoms such as a strong Th2 cell response, mucus production, and airway inflammation. To identify the mechanism by which C5aR signaling prevents this response, the researchers looked at immune cells called dendritic cells (DCs) in the mouse lungs. C5aR blockade was found to directly increase the ratio of pro-asthma "mDCs" to anti-asthma "pDCs" leading to Th2 sensitization, in the absence of allergen, but even more so following allergen exposure, demonstrating that C5aR prevents cell activation and recruitment.

Paradoxically, when C5aR was blocked after allergen exposure, the allergic response was dramatically prevented, and the severity of asthma-like symptoms was reduced, suggesting that C5aR increases the body's response to asthma-inducing stimuli only in an established allergic environment.

In an accompanying commentary, Bart N. Lambrecht from Erasmus University Medical Center in The Netherlands states that these studies "show that C5aR blockade promotes Th2 sensitization upon first exposure to inhaled allergen, whereas C5aR blockade during established inflammation suppresses the cardinal features of asthma."


Story Source:

The above story is based on materials provided by Journal of Clinical Investigation. Note: Materials may be edited for content and length.


Journal Reference:

  1. Kohl et al. A regulatory role for the C5a anaphylatoxin in type 2 immunity in asthma. Journal of Clinical Investigation, 2006; 116 (3): 783 DOI: 10.1172/JCI26582

Cite This Page:

Journal of Clinical Investigation. "Antibody Therapy Reduces Asthma In Mice." ScienceDaily. ScienceDaily, 6 March 2006. <www.sciencedaily.com/releases/2006/03/060306091153.htm>.
Journal of Clinical Investigation. (2006, March 6). Antibody Therapy Reduces Asthma In Mice. ScienceDaily. Retrieved September 3, 2014 from www.sciencedaily.com/releases/2006/03/060306091153.htm
Journal of Clinical Investigation. "Antibody Therapy Reduces Asthma In Mice." ScienceDaily. www.sciencedaily.com/releases/2006/03/060306091153.htm (accessed September 3, 2014).

Share This



More Health & Medicine News

Wednesday, September 3, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Snack Attack: Study Says Action Movies Make You Snack More

Snack Attack: Study Says Action Movies Make You Snack More

Newsy (Sep. 2, 2014) — You're more likely to gain weight while watching action flicks than you are watching other types of programming, says a new study published in JAMA. Video provided by Newsy
Powered by NewsLook.com
U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

Newsy (Sep. 2, 2014) — The U.N. says the problem is two-fold — quarantine zones and travel restrictions are limiting the movement of both people and food. Video provided by Newsy
Powered by NewsLook.com
Doctors Fear They're Losing Battle Against Ebola

Doctors Fear They're Losing Battle Against Ebola

AP (Sep. 2, 2014) — As a third American missionary is confirmed to have contracted Ebola in Liberia, doctors on the ground in West Africa fear they're losing the battle against the outbreak. (Sept. 2) Video provided by AP
Powered by NewsLook.com
Tech Giants Bet on 3D Headsets for Gaming, Healthcare

Tech Giants Bet on 3D Headsets for Gaming, Healthcare

AFP (Sep. 2, 2014) — When Facebook acquired the virtual reality hardware developer Oculus VR in March for $2 billion, CEO Mark Zuckerberg hailed the firm's technology as "a new communication platform." Duration: 02:24 Video provided by AFP
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