Bacteria use host's immune response to their competitive advantage

July 21, 2005

Millions of bacteria live within the recesses of our noses and upper respiratory tracts, waiting for a chance to infiltrate and infect. But long before these bacteria break through our immune defenses, they must first compete against other bacterial species to colonize the mucus-lined surfaces of our noses.

Competition between two common nose bacteria involves some interesting trickery, according to a new study in PLoS Pathogens. "We're looking at how bacteria use their host, and we've found that the presence of one species leads to the elimination of another," says Jeffrey Weiser, coauthor of the study and professor of pediatrics and microbiology at the University of Pennsylvania, School of Medicine.

In a mouse model, Haemophilus influenzae--a common bacterium that infects children--stimulates the immune system to send out specialized white blood cells that attack its competitor, Streptococcus pneumoniae--a leading cause of pneumonia. "It is striking that the host's response can so completely eliminate the competitor," says Weiser.

The findings also demonstrate how antibiotics and vaccines that target one microbe might inadvertently alter the competitive interactions among other species present.
-end-
Citation: Lysenko ES, Ratner AJ, Nelson AL, Weiser JN (2005) The role of innate immune responses in the outcome of interspecies competition for colonization of mucosal surfaces. PLoS Pathogens 1(1): e1.

PLEASE ADD THE LINK TO THE PUBLISHED ARTICLE IN ONLINE VERSIONS OF YOUR REPORT: http://dx.doi.org/10.1371/journal.ppat.0010001

CONTACT:

Jeffrey N. Weiser M.D.
University of Pennsylvania School of Medicine
402A Johnson Pavilion
3610 Hamilton Walk
Philadelphia, PA 19104-6076
215-573-3511; FAX 215-573-4856
weiser@mail.med.upenn.edu

The Public Library of Science (PLoS) is pleased to offer a preview of PLoS Pathogens (http://www.plospathogens.org), a new open-access, peer-reviewed journal that will premiere on September 30, 2005. The journal is led by Editor-in-Chief John A.T. Young, a professor in the Infectious Disease Laboratory at the Salk Institute for Biological Studies.

"Understanding pathogens and how they interact with their hosts is one of the most serious scientific challenges we face. New pathogens are emerging all the time, and others adapt to treatments efforts," Young says. The journal will publish rigorously peer-reviewed papers in the broad field of pathogens research, which includes bacteria, fungi, parasites, prions, and viruses.

Open access--free availability and unrestricted use­--to all articles published in the journal is central to the mission of PLoS Pathogens and the Public Library of Science. "Our open-access license means [the research published] is immediately available to scientists all over the world," the journal's editorial team explains.

PLEASE MENTION PLoS PATHOGENS (http://www.plospathogens.org/) AS THE SOURCE FOR THESE ARTICLES. THANK YOU.

All works published in PLoS Pathogens are open access. Everything is immediately available without cost to anyone, anywhere--to read, download, redistribute, include in databases, and otherwise use--subject only to the condition that the original authorship is properly attributed. Copyright is retained by the authors. The Public Library of Science uses the Creative Commons Attribution License.

CONTACT:
Rocky Choi
Publications Assistant
Public Library of Science
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San Francisco, CA USA 94107
U.S. :1-415-624-1210
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rchoi@plos.org

PLOS

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