J Med Microbiol Track the topics, authors and articles important to you
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

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
Right arrow Citation Map
Services
Right arrow Email this article to a friend
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 arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Vankerckhoven, V.
Right arrow Articles by Entenza, J. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Vankerckhoven, V.
Right arrow Articles by Entenza, J. M.
Agricola
Right arrow Articles by Vankerckhoven, V.
Right arrow Articles by Entenza, J. M.
J Med Microbiol 56 (2007), 1017-1024; DOI: 10.1099/jmm.0.46929-0
© 2007 Society for General Microbiology
ISSN 1473-5644

Infectivity of Lactobacillus rhamnosus and Lactobacillus paracasei isolates in a rat model of experimental endocarditis

Vanessa Vankerckhoven1, Philippe Moreillon2, Stéphane Piu2, Marlyse Giddey2, Geert Huys3, Marc Vancanneyt4, Herman Goossens1,5 and José M. Entenza2

1 Laboratory of Medical Microbiology, University of Antwerp, Belgium

2 Department of Fundamental Microbiology, University of Lausanne, Switzerland

3 Laboratory of Microbiology, Ghent University, Ghent, Belgium

4 BCCM/LMG Bacteria Collection, Ghent University, Ghent, Belgium

5 LUMC, Department of Medical Microbiology, Leiden, The Netherlands

Correspondence
José M. Entenza
jose.entenza{at}unil.ch

Received 6 September 2006
Accepted 16 April 2007

The potential pathogenicity of selected (potentially) probiotic and clinical isolates of Lactobacillus rhamnosus and Lactobacillus paracasei was investigated in a rat model of experimental endocarditis. In addition, adhesion properties of the lactobacilli for fibrinogen, fibronectin, collagen and laminin, as well as the killing activity of the platelet-microbicidal proteins fibrinopeptide A (FP-A) and connective tissue activating peptide 3 (CTAP-3), were assessed. The 90 % infective dose (ID90) of the L. rhamnosus endocarditis isolates varied between 106 and 107 c.f.u., whereas four of the six (potentially) probiotic L. rhamnosus isolates showed an ID90 that was at least 10-fold higher (108 c.f.u.) (P<0.001). In contrast, the two other probiotic L. rhamnosus isolates exhibited an ID90 (106 and 107 c.f.u.) comparable to the ID90 of the clinical isolates of this species investigated (P>0.05). Importantly, these two probiotic isolates shared the same fluorescent amplified fragment length polymorphism cluster type as the clinical isolate showing the lowest ID90 (106 c.f.u.). L. paracasei tended to have a lower infectivity than L. rhamnosus (ID90 of 107 to ≥108 c.f.u.). All isolates had comparable bacterial counts in cardiac vegetations (P>0.05). Except for one L. paracasei strain adhering to all substrates, all tested lactobacilli adhered only weakly or not at all. The platelet peptide FP-A did not show any microbicidal activity against the tested lactobacilli, whereas CTAP-3 killed the majority of the isolates. In general, these results indicate that probiotic lactobacilli display a lower infectivity in experimental endocarditis compared with true endocarditis pathogens. However, the difference in infectivity between L. rhamnosus endocarditis and (potentially) probiotic isolates could not be explained by differences in adherence or platelet microbicidal protein susceptibility. Other disease-promoting factors may exist in these organisms and warrant further investigation.

Abbreviations: FAFLP, fluorescent amplified fragment length polymorphism; ID90, 90 % infective dose.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
INT J SYST EVOL MICROBIOL J MED MICROBIOL MICROBIOLOGY J GEN VIROL ALL SGM JOURNALS
Copyright © 2007 Society for General Microbiology.