Featured Research

from universities, journals, and other organizations

Dendritic Cells Spark Smoldering Inflammation In Smokers' Lungs

Date:
October 28, 2009
Source:
Baylor College of Medicine
Summary:
Inflammation still ravages the lungs of some smokers years after they quit the habit. What sparks that smoldering destruction remained a mystery until researchers found that certain dendritic cells in the lung -- the cells that "present" a foreign antigen or protein to the immune system -- provoke production of destructive T-cells that attack a key protein called elastin, leading to death of lung tissue and emphysema.

Inflammation still ravages the lungs of some smokers years after they quit the habit.
Credit: iStockphoto

Inflammation still ravages the lungs of some smokers years after they quit the habit. What sparks that smoldering destruction remained a mystery until a consortium of researchers led by Baylor College of Medicine found that certain dendritic cells in the lung -- the cells that "present" a foreign antigen or protein to the immune system -- provoke production of destructive T-cells that attack a key protein called elastin, leading to death of lung tissue and emphysema.

A report of their work appears in the current issue of Science Transformational Medicine. The National Heart, Lung and Blood Institute estimates that 2 million Americans have emphysema, most of them over the age of 50 years. People with emphysema find it harder and harder to breathe as the lung's air sacs or alveoli are destroyed, causing holes in the lung and blocking airways. They have difficulty exchanging oxygen as their lungs become less elastic. Cigarette smoking is the greatest risk factor for the disease that contributes to as many as 100,000 deaths each year.

In previous work, Dr. Farrah Kheradmand, associate professor of medicine -- pulmonary and immunology at BCM, and colleagues had shown that T-helper cells and some enzymes in the lung destroyed tissue in the lungs of emphysema patients. She credits BCM graduate student Ming Shan with pushing the project forward with the work in the current report.

She and her colleagues found that a subset of antigen-presenting cells in the lung are programmed to turn peripheral blood cells into the cells that are activated and are associated with autoimmune inflammation. They also found that elastin peptides can activate T cells -a sign that elastin is acting as an auto-antigen.

"This has implications for something that is important and biologically relevant," said Kheradmand. "Smokers are also at risk for diseases of the blood vessels such as the carotid artery and aorta. These blood vessels are also enriched in elastin. We believe that particular cells circulating in the body could react to elastin molecule at these remote sites."

This may help explain some of the cardiovascular and other complications associated with smoking tobacco. For example, skin is rich in elastin. The skin of smokers loses elasticity.

"We believe that this systemic inflammation that may initially affect the lung could also affect other parts of the body," she said.

She and fellow senior author Dr. David Corry, professor of medicine -- pulmonary and immunology, and her colleagues used lung tissue taken from emphysema patients who were undergoing surgery anyway to determine which cells are present and their functions in the lung.

"These live cells are the center of what we studied," she said.

She and her colleagues found that some patients did not have the elastin-specific cells in their lungs, even though they had smoked.

"The Holy Grail is to find smokers who are destined to develop auto-reactive cells before the disease is fully manifested," she said. She said they hope to come with a test for T-cells that attack elastin that could be used in the doctor's office. However, she said, such a test would only identify patients at higher risk for emphysema and other elastin-associated diseases. It would not identify people at higher risk of lung cancer, for example.

"It is not a good excuse to smoke or continue smoking," she said.

Others who took part in the study include Han-Fang Cheng Li-zhen Song and Luz Roberts of BCM, Linda Green and Joan Hacken-Bitar of the Michael E. DeBakey Veterans Affairs Medical Center in Houston, Joseph Huh and Faisal Bakaeen of MEDVAMC and BCM, Harvey O. Coxson and Claudine Storness-Bliss of Vancouver General Hospital in British Columbia, Canada; Mahesh Ramchandani of The Methodist Hospital in Houston, and Seung-Hyo Lee of the Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.

Funding for this work came from the U.S. National Institutes of Health and the American Heart Association.


Story Source:

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


Cite This Page:

Baylor College of Medicine. "Dendritic Cells Spark Smoldering Inflammation In Smokers' Lungs." ScienceDaily. ScienceDaily, 28 October 2009. <www.sciencedaily.com/releases/2009/10/091028142229.htm>.
Baylor College of Medicine. (2009, October 28). Dendritic Cells Spark Smoldering Inflammation In Smokers' Lungs. ScienceDaily. Retrieved October 1, 2014 from www.sciencedaily.com/releases/2009/10/091028142229.htm
Baylor College of Medicine. "Dendritic Cells Spark Smoldering Inflammation In Smokers' Lungs." ScienceDaily. www.sciencedaily.com/releases/2009/10/091028142229.htm (accessed October 1, 2014).

Share This



More Health & Medicine News

Wednesday, October 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola Cases Keep Coming for Monrovia's Island Hospital

Ebola Cases Keep Coming for Monrovia's Island Hospital

AFP (Oct. 1, 2014) A look inside Monrovia's Island Hospital, a key treatment centre in the fight against Ebola in Liberia's capital city. Duration: 00:34 Video provided by AFP
Powered by NewsLook.com
Ebola Puts Stress on Liberian Health Workers

Ebola Puts Stress on Liberian Health Workers

AP (Oct. 1, 2014) The Ebola outbreak is putting stress on first responders in Liberia. Ambulance drivers say they are struggling with chronic shortages of safety equipment and patients who don't want to go to the hospital. (Oct. 1) Video provided by AP
Powered by NewsLook.com
Doctors Reassure Public Ebola Patient Won't Cause Outbreak

Doctors Reassure Public Ebola Patient Won't Cause Outbreak

Newsy (Sep. 30, 2014) After the announcement that the first U.S. patient had been diagnosed with Ebola, doctors were quick to say a U.S. outbreak is highly unlikely. Video provided by Newsy
Powered by NewsLook.com
TX Hospital Confirms Patient Admitted With Ebola

TX Hospital Confirms Patient Admitted With Ebola

AP (Sep. 30, 2014) Medical officials from Texas Health Presbyterian Hospital confirm they are treating a patient with the Ebola virus, the first case found in the US. (Sept. 30 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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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