Featured Research

from universities, journals, and other organizations

Body's Defenses May Worsen Chronic Lung Diseases In Smokers

Date:
February 18, 2009
Source:
University of Cincinnati
Summary:
Although the immune system is designed to protect the body from harm, it may actually worsen one of the most difficult-to-treat respiratory diseases: chronic obstructive pulmonary disorder, according to new University of Cincinnati research.

COPD is a progressive pulmonary disease believed to be caused by long-term cigarette smoking. The irreversible and incurable condition is characterized by emphysema and severe inflammation of the lung tissue.
Credit: Image courtesy of University of Cincinnati

Although the immune system is designed to protect the body from harm, it may actually worsen one of the most difficult-to-treat respiratory diseases: chronic obstructive pulmonary disorder (COPD), according to new University of Cincinnati (UC) research.

In a preclinical research study, UC environmental health scientists have identified a link between cigarette smoke and activation of a specific cellular receptor (NKG2D) critical to immune system activation. They say the finding is key to understanding COPD disease progression and developing future interventional drug therapies.  

“People have historically believed that if you smoke, you suppress the immune system. We’ve shown that you actually activate certain parts of the immune system and it could potentially work against you,” explains Michael Borchers, PhD, lead investigator of the study and UC assistant professor of environmental health.

Borchers and his team report their findings in the March 2009 issue of the Journal of Clinical Investigation. The study appears online ahead of print Feb. 9, 2009. It is the first study to report data defining a link between the immune system and COPD disease progression and severity.

COPD is a progressive pulmonary disease believed to be caused by long-term cigarette smoking. The irreversible and incurable condition is characterized by emphysema and severe inflammation of the lung tissue.

Previous research had suggested that immune cells (lymphocytes) contributed to chronic inflammation, a key indicator of COPD; however, it was unclear whether this caused extensive cellular damage.

For this study, Borchers’ team developed a transgenic mouse model to further examine how the immune system responds to chronic inflammation indicative of COPD. His team hypothesized that when tissue was damaged, the cells would send signals to the immune system indicating they are transformed—similar to cancer or virally infected cells—and must be destroyed.

Scientists examined molecular signaling pathways in lung tissue exposed to cigarette smoke and found a strong correlation between cellular stress signals, activation of the immune system and development of COPD-like disease.

This method was repeated and cross-referenced in tissue samples from a human cohort that included non-smokers, smokers with COPD and smokers who did not develop COPD. In patients who had never smoked, there was a complete absence of the NKG2D signal. Current and former smokers who developed the disease expressed signals that correlated with severe COPD disease.

By combining both sets of data, they determined that cigarette smoke set off a molecular chain of events resulting in activation of a specific receptor—NKG2D—in lung cells, causing the immune system to attack stressed (damaged) lung tissue.

“Our study is evidence that when the lungs are exposed to chronic damage from cigarette smoke, at some point that damage exceeds the body’s natural ability to repair tissue and can start to contribute to COPD instead of protecting against it,” Borchers says.

Borchers intends to expand this research using other genetically altered mouse models to explore the relationship between the NKG2D receptor and other immune pathways involved in of alterations in the immune system of COPD patients.

Funding for the multi-institutional study comes from the National Institute of Environmental Health Sciences. UC thoracic surgeons Michael Reed, MD, and Sandra Starnes, MD, and investigators at the Institut Municipal d’Investigaciσ Mθdica in Barcelona, Spain, provided tissue samples for the study.


Story Source:

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


Cite This Page:

University of Cincinnati. "Body's Defenses May Worsen Chronic Lung Diseases In Smokers." ScienceDaily. ScienceDaily, 18 February 2009. <www.sciencedaily.com/releases/2009/02/090209205307.htm>.
University of Cincinnati. (2009, February 18). Body's Defenses May Worsen Chronic Lung Diseases In Smokers. ScienceDaily. Retrieved August 30, 2014 from www.sciencedaily.com/releases/2009/02/090209205307.htm
University of Cincinnati. "Body's Defenses May Worsen Chronic Lung Diseases In Smokers." ScienceDaily. www.sciencedaily.com/releases/2009/02/090209205307.htm (accessed August 30, 2014).

Share This




More Health & Medicine News

Saturday, August 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) — A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Liberia Continues Fight Against Ebola

Liberia Continues Fight Against Ebola

AFP (Aug. 30, 2014) — Authorities in Liberia try to stem the spread of the Ebola epidemic by raising awareness and setting up sanitation units for people to wash their hands. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
California Passes 'yes-Means-Yes' Campus Sexual Assault Bill

California Passes 'yes-Means-Yes' Campus Sexual Assault Bill

Reuters - US Online Video (Aug. 30, 2014) — California lawmakers pass a bill requiring universities to adopt "affirmative consent" language in their definitions of consensual sex, part of a nationwide drive to curb sexual assault on campuses. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
3 Things To Know About The Ebola Outbreak's Progression

3 Things To Know About The Ebola Outbreak's Progression

Newsy (Aug. 29, 2014) — Here are three things you need to know about the deadly Ebola outbreak's progression this week. Video provided by Newsy
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