Featured Research

from universities, journals, and other organizations

How salmonella avoids the body's immune response

Date:
March 14, 2012
Source:
University of California - Irvine
Summary:
Researchers have discovered how salmonella, a bacterium found in contaminated raw foods that causes major gastrointestinal distress in humans, thrives in the digestive tract despite the immune system's best efforts to destroy it.

UC Irvine researchers have discovered how salmonella, a bacterium found in contaminated raw foods that causes major gastrointestinal distress in humans, thrives in the digestive tract despite the immune system's best efforts to destroy it.

Their findings help explain why salmonella is difficult to eradicate and point to new approaches for possible treatments. Most people infected with salmonella suffer from diarrhea, fever and abdominal cramps for up to seven days before the infection resolves.

Lead researcher Manuela Raffatellu, a UCI assistant professor of microbiology & molecular genetics, and colleagues identified a novel molecular mechanism that allows salmonella to survive. Results of their study appear in the March issue of Cell Host & Microbe.

Pathogens like salmonella flourish and cause disease in humans through a process by which they acquire metal ions, such as zinc, from the body. One of the body's key immune responses is to flood the infected area with antimicrobial proteins that include calprotectin, which removes zinc. Without enough of this vital element, most pathogens eventually die.

Raffatellu's team found, however, that salmonellae overcome this immune response by expressing specialized transporter proteins that enable the bacteria to acquire zinc in spite of calprotectin reducing the amount available in the digestive tract. This distinctive mechanism lets salmonellae continue proliferating.

At the same time, calprotectin inadvertently promotes salmonella growth by killing the microbes that normally reside within the intestines and help the immune system battle pathogenic bacteria.

"We're beginning to learn more about the mechanisms that allow pathogens like salmonella to evade our natural defenses and make us sick," Raffatellu said. "In light of this, if we can devise therapies that block the acquisition of zinc and other metals by salmonella specifically, we can fight this infection."

Additionally, she said, the new findings may have relevance for other illnesses, such as inflammatory bowel disease and colon cancer, in which high levels of calprotectin are detected.

Also contributing to the study, which was supported by grants from the National Institutes of Health, were Janet Z. Liu, Stefan Jellbauer, Adam Poe, Vivian Ton, Michele Pesciaroli, Martin Hosking, Robert A. Edwards and Thomas E. Lane of UCI; Thomas Kehl-Fie, Nicole A. Restrepo, Walter J. Chazin and Eric P. Skaar of Vanderbilt University; Andrea Battistoni of the University of Rome; Thomas Vogl and Johannes Roth of the University of Munster, Germany; and Paolo Pasquali of the Superior Health Institute in Rome.


Story Source:

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


Journal Reference:

  1. Janet Z. Liu, Stefan Jellbauer, Adam J. Poe, Vivian Ton, Michele Pesciaroli, Thomas E. Kehl-Fie, Nicole A. Restrepo, Martin P. Hosking, Robert A. Edwards, Andrea Battistoni et al. Zinc Sequestration by the Neutrophil Protein Calprotectin Enhances Salmonella Growth in the Inflamed Gut. Cell Host & Microbe, 15 March 2012 DOI: 10.1016/j.chom.2012.01.017

Cite This Page:

University of California - Irvine. "How salmonella avoids the body's immune response." ScienceDaily. ScienceDaily, 14 March 2012. <www.sciencedaily.com/releases/2012/03/120314125923.htm>.
University of California - Irvine. (2012, March 14). How salmonella avoids the body's immune response. ScienceDaily. Retrieved April 17, 2014 from www.sciencedaily.com/releases/2012/03/120314125923.htm
University of California - Irvine. "How salmonella avoids the body's immune response." ScienceDaily. www.sciencedaily.com/releases/2012/03/120314125923.htm (accessed April 17, 2014).

Share This



More Health & Medicine News

Thursday, April 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Could Even Casual Marijuana Use Alter Your Brain?

Could Even Casual Marijuana Use Alter Your Brain?

Newsy (Apr. 16, 2014) A new study conducted by researchers at Northwestern and Harvard suggests even casual marijuana use can alter your brain. Video provided by Newsy
Powered by NewsLook.com
Thousands Of Vials Of SARS Virus Go Missing

Thousands Of Vials Of SARS Virus Go Missing

Newsy (Apr. 16, 2014) A research institute in Paris somehow misplaced more than 2,000 vials of the deadly SARS virus. Video provided by Newsy
Powered by NewsLook.com
Formerly Conjoined Twins Released From Dallas Hospital

Formerly Conjoined Twins Released From Dallas Hospital

Newsy (Apr. 16, 2014) Conjoined twins Emmett and Owen Ezell were separated by doctors in August. Now, nearly nine months later, they're being released from the hospital. Video provided by Newsy
Powered by NewsLook.com
Ebola Outbreak Now Linked To 121 Deaths

Ebola Outbreak Now Linked To 121 Deaths

Newsy (Apr. 15, 2014) The ebola virus outbreak in West Africa is now linked to 121 deaths. Health officials fear the virus will continue to spread in urban areas. 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