Host-pathogen interaction with reference to uropathogenic E. coli
-
1
Karolinska University, Departement of Clinical Microbiology, Sweden
Urinary tract infections are among the most common infectious diseases worldwide, primarily caused by uropathogenic E. coli. With emerging bacterial resistance against conventional antimicrobial therapy, including multi drug resistance, there is a need for novel strategies to treat and prevent urinary tract infections. It is well known that the innate immune system takes active part in the host-pathogen interaction. Antimicrobial peptides like cathelicidin, LL-37, are produced and secreted by the bladder epithelium and have been shown to fend off invading bacteria and thereby protect the host from infection. To circumvent eradication, bacteria form biofilm. Formation of biofilm includes surface adhesion, cell-cell interactions and production of extracellular matrix, which offers advantage to the bacteria. Biofilm formation is promoted by bacterial components like cellulose and curli fimbriae. Cellulose reduces immune induction and hence delays bacterial elimination from the kidneys. Curli fimbriae, on the other hand, increase the induction of the proinflammatory cytokine IL-8. In addition, curli expression promotes resistance to LL-37 by binding the peptide before reaching the bacterial cell membrane and exhibiting its bactericidal activity. However, LL-37 prevents the formation of new curli fimbriae by inhibiting polymerization of the major subunit CsgA. Even relatively low concentrations of LL-37 inhibit curli-mediated biofilm formation. To enhance the endogenous cathelicidin, LL-37, would therefore be a possible way to fight urinary tract infections. The observation that vitamin D can induce LL-37 in the urinary bladder, followed by enhanced killing of invading bacteria, is therefore of interest and could serve as a possible complementary treatment strategy to fight urinary tract infections.
Keywords:
Biofilm,
Cellulose,
Curli fimbriae,
LL-37,
UPEC,
Urinary Tract,
Vitamin D
Conference:
ECMIS - E. coli and the Mucosal Immune System : Interaction, Modulation and Vaccination, Ghent, Belgium, 2 Jul - 5 Jul, 2011.
Presentation Type:
Oral Presentation
Topic:
Immune responses in humans, ruminants, pigs and poultry
Citation:
Brauner
A
(2011). Host-pathogen interaction with reference to uropathogenic E. coli.
Front. Immunol.
Conference Abstract:
ECMIS - E. coli and the Mucosal Immune System : Interaction, Modulation and Vaccination.
doi: 10.3389/conf.fimmu.2011.01.00005
Copyright:
The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers.
They are made available through the Frontiers publishing platform as a service to conference organizers and presenters.
The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated.
Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed.
For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions.
Received:
22 Sep 2011;
Published Online:
26 Sep 2011.
*
Correspondence:
Prof. Annelie Brauner, Karolinska University, Departement of Clinical Microbiology, Stockholm, Sweden, Annelie.Brauner@ki.se