Featured Research

from universities, journals, and other organizations

Research Elucidates Way Lungs Fight Bacteria And Prevent Infection

Date:
January 29, 2009
Source:
Columbia University Medical Center
Summary:
Airway epithelial cells initiate an immune response to inhaled bacteria by signaling for white blood cells to move from the bloodstream into the lungs and airway to fight potential infection. Researchers have demonstrated that this signaling cascade includes the activation of epithelial proteases, a type of enzyme capable of opening the junctions between the cells in the airway mucosa, to enable the white blood cells to get through to the site of the infection.

Process in which bacteria in the lung trigger an immune response allowing a white blood cell to move into the airspace.
Credit: Chun et al

Actor and pancreatic cancer patient Patrick Swayze's recent hospitalization with pneumonia as a result of his compromised immune system underscores the sensitivity of the lungs: many patients die from lung complications of a disease, rather than the disease itself.

Related Articles


Lungs are delicate and exposed to the environment, almost like an open wound. Consequently, the body has developed an elaborate immuno-defense system to combat inhaled pathogens and bacteria – in a healthy individual, this system effectively blocks hundreds of potentially sickening assaults daily.

It works like this: airway epithelial cells initiate an immune response to inhaled bacteria by signaling for white blood cells to move from the bloodstream into the lungs and airway to fight potential infection.

For the first time, researchers at Columbia University Medical Center have demonstrated that this signaling cascade includes the activation of epithelial proteases, a type of enzyme capable of opening the junctions between the cells in the airway mucosa, to enable the white blood cells to get through to the site of the infection. The opening of these junctions is initiated by a change in calcium levels.

The work by Drs. Jarin Chun and Alice Prince in the Departments of Pharmacology and Pediatrics at Columbia's College of Physicians and Surgeons was published Jan. 22, 2009 in the journal Cell Host & Microbe.

Getting white blood cells to the site of an infection, however, is often a double-edged sword. On the one hand, having as many white blood cells as possible at the site of an infection is beneficial, but on the other hand too many white blood cells can lead to excessive inflammation, interfering with breathing and damaging the airways.

Cystic fibrosis is one disease where this work might have particular import, Dr. Chun says. People with cystic fibrosis possess an abnormal gene that causes normal mucus to become thick and sticky, leaving the lung more prone to infection and inflammation, while still killing infection-causing bacteria.

The findings, in mice, demonstrate a way to inhibit proteases and restrict the junctions between cells in the airway mucosa, meaning that fewer white blood cells can get into the airway – causing less inflammation.

Thus, epithelial proteases could be an important target to control inflammation in the lung, and could serve as the basis for the development of novel drugs to help the human body get the optimal number of white blood cells to an infection site without letting inflammation spiral out of control.


Story Source:

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


Cite This Page:

Columbia University Medical Center. "Research Elucidates Way Lungs Fight Bacteria And Prevent Infection." ScienceDaily. ScienceDaily, 29 January 2009. <www.sciencedaily.com/releases/2009/01/090123101205.htm>.
Columbia University Medical Center. (2009, January 29). Research Elucidates Way Lungs Fight Bacteria And Prevent Infection. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2009/01/090123101205.htm
Columbia University Medical Center. "Research Elucidates Way Lungs Fight Bacteria And Prevent Infection." ScienceDaily. www.sciencedaily.com/releases/2009/01/090123101205.htm (accessed October 31, 2014).

Share This



More Health & Medicine News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

U.S. Ebola Response Measures Demonstrated

U.S. Ebola Response Measures Demonstrated

AP (Oct. 31, 2014) Officials in the Washington area showed off Ebola response measures being taken at Dulles International Airport and the National Institutes of Health. (Oct. 31) Video provided by AP
Powered by NewsLook.com
Fauci Says Ebola Risk in US "essentially Zero"

Fauci Says Ebola Risk in US "essentially Zero"

AP (Oct. 30, 2014) NIAID Director Anthony Fauci said the risk of Ebola becoming an epidemic in the U.S. is essentially zero Thursday at the Washington Ideas Forum. He also said an Ebola vaccine will be tested in West Africa in the next few months. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Nurse Defies Ebola Quarantine With Bike Ride

Nurse Defies Ebola Quarantine With Bike Ride

AP (Oct. 30, 2014) A nurse who vowed to defy Maine's voluntary quarantine for health care workers who treated Ebola patients followed through on her promise Thursday, leaving her home for an hour-long bike ride. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Pot-Infused Edibles Raise Concerns in Colorado

Pot-Infused Edibles Raise Concerns in Colorado

AFP (Oct. 30, 2014) Colorado may have legalized marijuana for recreational use, but the debate around the decision still continues, with a recent - failed - attempt to ban cannabis-infused edibles. Duration: 01:53 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:

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