Saturday, July 17, 2010

interspecies quorum sensing?

mBio | ABSTRACT Otitis media (OM) is among the leading diseases of childhood and is caused by opportunists that reside within the nasopharynx, such as Haemophilus influenzae and Moraxella catarrhalis. As with most airway infections, it is now clear that OM infections involve multiple organisms. This study addresses the hypothesis that polymicrobial infection alters the course, severity, and/or treatability of OM disease. The results clearly show that coinfection with H. influenzae and M. catarrhalis promotes the increased resistance of biofilms to antibiotics and host clearance. Using H. influenzae mutants with known biofilm defects, these phenotypes were shown to relate to biofilm maturation and autoinducer-2 (AI-2) quorum signaling. In support of the latter mechanism, chemically synthesized AI-2 (dihydroxypentanedione [DPD]) promoted increased M. catarrhalis biofilm formation and resistance to antibiotics. In the chinchilla infection model of OM, polymicrobial infection promoted M. catarrhalis persistence beyond the levels seen in animals infected with M. catarrhalis alone. Notably, no such enhancement of M. catarrhalis persistence was observed in animals infected with M. catarrhalis and a quorum signaling-deficient H. influenzae luxS mutant strain. We thus conclude that H. influenzae promotes M. catarrhalis persistence within polymicrobial biofilms via interspecies quorum signaling. AI-2 may therefore represent an ideal target for disruption of chronic polymicrobial infections. Moreover, these results strongly imply that successful vaccination against the unencapsulated H. influenzae strains that cause airway infections may also significantly impact chronic M. catarrhalis disease by removing a reservoir of the AI-2 signal that promotes M. catarrhalis persistence within biofilm.

IMPORTANCE Otitis media (OM) is one of the most common childhood infections and is a leading reason for antibiotic prescriptions to children. Chronic and recurrent OM involves persistence of bacteria within biofilm communities, a state in which they are highly resistant to immune clearance and antibiotic treatment. While it is clear that most of these infections involve multiple species, the vast majority of knowledge about OM infections has been derived from work involving single bacterial species. There is a pressing need for better understanding of the impact of polymicrobial infection on the course, severity, and treatability of OM disease. In this study, we show that communication between bacterial species promotes bacterial persistence and resistance to antibiotics, which are important considerations in the diagnosis, prevention, and treatment of OM. Moreover, the results of this study indicate that successful preventive measures against H. influenzae could reduce the levels of disease caused by M. catarrhalis.

4 comments:

Anonymous said...

qmws [url=http://stylomontblancsoldes.fr]stylo mont blanc[/url] wurljo http://stylomontblancsoldes.fr zcmw [url=http://montblancstylopascher.fr]mont blanc[/url] dmohmi http://montblancstylopascher.fr rwpa [url=http://montblancpenscheap.co.uk]cheap mont blanc[/url] cfzyen http://montblancpenscheap.co.uk rgdf [url=http://montblancukstores.co.uk]mont blanc pens[/url] qjecwk http://montblancukstores.co.uk rmhg [url=http://montblancpensuksale.co.uk]mont blanc[/url] anbzwe http://montblancpensuksale.co.uk korr [url=http://montblancpensuksale.co.uk]mont blanc uk[/url] hmjewg http://montblancpensuksale.co.uk rezd

Anonymous said...

xecdy [url=http://drdrebeatsuksales.co.uk]dr dre beats[/url] meggr http://drdrebeatsuksales.co.uk mcryy [url=http://beatsbydreukforsales.co.uk]beats by dre[/url] zyrji http://beatsbydreukforsales.co.uk gxeff [url=http://cheapdrebeatsuksale.co.uk]cheap beats by dre[/url] vrfmp http://cheapdrebeatsuksale.co.uk atyqy [url=http://cheapestbeatsheadphones.co.uk]cheap beats by dre[/url] ljrgf http://cheapestbeatsheadphones.co.uk woexd [url=http://cheapestdrebeats.co.uk]beats by dr dre[/url] nmzrr http://cheapestdrebeats.co.uk gcgpd [url=http://cheapdrebeatssale.co.uk]beats by dre uk[/url] tpdbz http://cheapdrebeatssale.co.uk yqhd

Anonymous said...

obu [url=http://www.beatsbydrename.com]Beats By Dre[/url] tic http://www.beatsbydrename.com shj [url=http://www.cheapbeatsbydrelo.com]Dr Dre Beats[/url] sti http://www.cheapbeatsbydrelo.com uvq [url=http://www.drdrebeatswe.com]Dr Dre Beats[/url] emq http://www.drdrebeatswe.com pvu [url=http://www.cheapbeatsbydrewe.com]Cheap Beats By Dre[/url] xin http://www.cheapbeatsbydrewe.com vke [url=http://www.beatsbydrewe.com]Dr Dre Beats[/url] tdb http://www.beatsbydrewe.com osm [url=http://www.celineluggagetotediscount.com]Celine Handbags[/url] kju http://www.celineluggagetotediscount.com noe [url=http://www.celinehandbagsdiscount.com]Celine Handbags[/url] rva http://www.celinehandbagsdiscount.com ass

Anonymous said...

bam [url=http://www.celineluggagetotediscount.com]Celine Handbags[/url] uam http://www.celineluggagetotediscount.com xmp [url=http://www.celinehandbagsdiscount.com]Celine Handbags[/url] kjl http://www.celinehandbagsdiscount.com esb [url=http://www.celinebagxiao.com]Celine Bag[/url] puy http://www.celinebagxiao.com ghz [url=http://www.celinehandbagswe.com]Celine Bag[/url] uvn http://www.celinehandbagswe.com ozi [url=http://www.drdrebeatsname.com]Cheap Beats By Dre[/url] nnu http://www.drdrebeatsname.com xlv