IAI FigSearch
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by van Rossum, A. M. C.
Right arrow Articles by Weiser, J. N.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by van Rossum, A. M. C.
Right arrow Articles by Weiser, J. N.

 Previous Article  |  Next Article 

Infection and Immunity, November 2005, p. 7718-7726, Vol. 73, No. 11
0019-9567/05/$08.00+0     doi:10.1128/IAI.73.11.7718-7726.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Host and Bacterial Factors Contributing to the Clearance of Colonization by Streptococcus pneumoniae in a Murine Model

Annemarie M. C. van Rossum,{dagger} Elena S. Lysenko, and Jeffrey N. Weiser*

Departments of Microbiology and Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania

Received 18 May 2005/ Returned for modification 20 June 2005/ Accepted 1 August 2005

Nasopharyngeal colonization is the first step in the interaction between Streptococcus pneumoniae (the pneumococcus) and its human host. Factors that contribute to clearance of colonization are likely to affect the spread of the pneumococcus and the rate of pneumococcal disease in the population. To identify host and bacterial factors contributing to this process, we examined the time course of colonization using genetically modified mice and pneumococci. Severe combined immunodeficient mice remained persistently colonized (>6 weeks). Major histocompatibility complex II-deficient mice, but not µMT mice, were unable to clear colonization and showed a diminished T helper 1 response. Thus, CD4+ T cells, rather than the generation of specific antibody, appear to be required for effective Th1-mediated clearance. In addition, the microbial pattern recognition receptor toll-like receptor 2 (TLR2), but not TLR4, was necessary for efficient clearance of colonization. In contrast, no role of complement component 3, inducible nitric oxide synthetase, interleukin 12 (IL-12), or IL-4 could be demonstrated. Expression of the pneumococcal toxin pneumolysin enhanced acute localized inflammatory responses and promoted clearance of colonization in a TLR4-independent manner. We conclude that both innate and CD4+ T-cell-mediated immunity and proinflammatory bacterial factors, rather than a humoral adaptive immune response, are important for clearance of S. pneumoniae from the murine nasopharynx.

* Corresponding author. Mailing address: University of Pennsylvania, 402A Johnson Pavilion, Philadelphia, PA 19104-6076. Phone: (215) 573-3511. Fax: (215) 573-4856. E-mail: weiser{at}mail.med.upenn.edu.

Editor: F. C. Fang

{dagger} Present address: Department of Pediatrics, Erasmus Medical Center—Sophia Children's Hospital, Rotterdam, The Netherlands.

Infection and Immunity, November 2005, p. 7718-7726, Vol. 73, No. 11
0019-9567/05/$08.00+0     doi:10.1128/IAI.73.11.7718-7726.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. J. Virol. Eukaryot. Cell
Microbiol. Mol. Biol. Rev. Clin. Vaccine Immunol. All ASM Journals

Copyright © 2005 by the American Society for Microbiology. All rights reserved.