Featured Research

from universities, journals, and other organizations

How Superbugs Control Their Lethal Weapons

Date:
May 27, 2009
Source:
University of Western Ontario
Summary:
It appears some superbugs have evolved to develop the ability to manipulate the immune system to everyone's advantage. Scientists have discovered some processes that reduce the lethal effects of toxins from superbugs, allowing humans and microbes to co-evolve. This discovery may lead to novel alternatives to antibiotics.

It appears that some superbugs have evolved to develop the ability to manipulate the immune system to everyone's advantage.

A team of researchers at The University of Western Ontario, led by Joaquin (Quim) Madrenas of the Robarts Research Institute, has discovered some processes that reduce the lethal effects of toxins from superbugs, allowing humans and microbes to co-evolve. This discovery may lead to novel alternatives to antibiotics that specifically target the toxic effects of these superbugs.

Madrenas holds a Canada Research Chair in Immunobiology and is a Professor of Microbiology & Immunology, and Medicine at the Schulich School of Medicine & Dentistry at Western. He also is head of Immunology at Robarts Research Institute and Director of the FOCIS Centre for Clinical Immunology and Immunotherapeutics.

Staphylococcus (staph) aureus is the leading cause of infections in hospitals and the second most common cause of infections in the general population. By itself, it is linked to more than half a million hospital admissions a year in North America with estimated costs of more than $6 billion per year. Among the many weapons produced by this superbug, the most potent and lethal ones are known as superantigens. These lethal weapons cause massive and harmful activation of the immune system that leads to Toxic Shock Syndrome (TSS). TSS is a very serious disease that carries a high mortality, for which we do not have a specific treatment.

Scientists have been puzzled as to why, when the body is directly exposed to the TSS toxins, a human can die within hours whereas individuals may carry toxin-producing staph and not get sick or die.

What has the staph bug got that prevents the immune system of the host from being kicked into high gear? Madrenas and his collaborators at Western, Calgary and Chicago have identified the process that allows the bug to stay in the body without causing that massive activation of the immune system.

The secret lies in molecules found in the cell wall of staph. These molecules bind to receptors known as TLR2 on immune cells of the host triggering the production of a protein called IL-10, an anti-inflammatory molecule that will prevent TSS.

"It is clear that staph superbugs have developed strategies to control the toxicity of its lethal superantigen toxins, thereby preventing TSS. We believe that this is an important mechanism that warrants continued investigation. It also illustrates that evolution may operate not only by competition but also by networking ultimately leading to peaceful co-existence" says Madrenas.

Based on these studies, Madrenas and colleagues have developed a computer model that will help predict the outcomes of encounters between staph and a host, and will reveal new aspects of these encounters.

The multidisciplinary team led by Madrenas includes David Heinrichs, Ewa Cairns, Mansour Haeryfar, and John McCormick of the Departments of Microbiology and Immunology, and Medicine at The University of Western Ontario, as well as Paul Kubes from the University of Calgary and Gary An from Northwestern University in Chicago.

The findings are being published in the journal Nature Medicine and are available online May 24, 2009. The research was funded by the Canadian Institutes of Health Research and the Kidney Foundation of Canada.


Story Source:

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


Cite This Page:

University of Western Ontario. "How Superbugs Control Their Lethal Weapons." ScienceDaily. ScienceDaily, 27 May 2009. <www.sciencedaily.com/releases/2009/05/090524170653.htm>.
University of Western Ontario. (2009, May 27). How Superbugs Control Their Lethal Weapons. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2009/05/090524170653.htm
University of Western Ontario. "How Superbugs Control Their Lethal Weapons." ScienceDaily. www.sciencedaily.com/releases/2009/05/090524170653.htm (accessed July 23, 2014).

Share This




More Health & Medicine News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Courts Conflicted Over Healthcare Law

Courts Conflicted Over Healthcare Law

AP (July 22, 2014) Two federal appeals courts issued conflicting rulings Tuesday on the legality of the federally-run healthcare exchange that operates in 36 states. (July 22) Video provided by AP
Powered by NewsLook.com
Why Do People Believe We Only Use 10 Percent Of Our Brains?

Why Do People Believe We Only Use 10 Percent Of Our Brains?

Newsy (July 22, 2014) The new sci-fi thriller "Lucy" is making people question whether we really use all our brainpower. But, as scientists have insisted for years, we do. Video provided by Newsy
Powered by NewsLook.com
Scientists Find New Way To Make Human Platelets

Scientists Find New Way To Make Human Platelets

Newsy (July 22, 2014) Boston scientists have discovered a new way to create fully functioning human platelets using a bioreactor and human stem cells. Video provided by Newsy
Powered by NewsLook.com
Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

TheStreet (July 21, 2014) New research shows Gilead Science's drug Sovaldi helps in curing hepatitis C in those who suffer from HIV. In a medical study, the combination of Gilead's Hep C drug with anti-viral drug Ribavirin cured 76% of HIV-positive patients suffering from the most common hepatitis C strain. Hepatitis C and related complications have been a top cause of death in HIV-positive patients. Typical medication used to treat the disease, including interferon proteins, tended to react badly with HIV drugs. However, Sovaldi's %1,000-a-pill price tag could limit the number of patients able to access the treatment. TheStreet's Keris Lahiff reports from New York. Video provided by TheStreet
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