Journal article
Comparison of Staphylococcus aureus strains for ability to cause infective endocarditis and lethal sepsis in rabbits
Frontiers in cellular and infection microbiology, Vol.2, pp.18-18
2012
DOI: 10.3389/fcimb.2012.00018
PMCID: PMC3417574
PMID: 22919610
Abstract
Staphylococcus aureus
is a major cause of infective endocarditis (IE) and sepsis. Both methicillin-resistant (MRSA) and methicillin-sensitive (MSSA) strains cause these illnesses. Common
S. aureus
strains include pulsed-field gel electrophoresis (PFGE) types USA200, 300, and 400 types where we hypothesize that secreted virulence factors contribute to both IE and sepsis. Rabbit cardiac physiology is considered similar to humans, and rabbits exhibit susceptibility to
S. aureus
superantigens (SAgs) and cytolysins. As such, rabbits are an excellent model for studying IE and sepsis, which over the course of four days develop IE vegetations and/or fatal septicemia. We examined the ability of MRSA and MSSA strains (4 USA200, 2 USA300, 2 USA400, and three additional common strains, FRI1169, Newman, and COL) to cause vegetations and lethal sepsis in rabbits. USA200, TSST-1
+
strains that produce only low amounts of α-toxin, exhibited modest LD
50
in sepsis (1 × 10
8
– 5 × 10
8
) colony-forming units (CFUs), and 3/4 caused significant IE. USA200 strain MNPE, which produces high-levels of α-toxin, was both highly lethal (LD
50
5 × 10
6
CFUs) and effective in causing IE. In contrast, USA300 strains were highly effective in causing lethal sepsis (LD
50
s 1 × 10
6
and 5 × 10
7
CFUs) but were minimally capable of causing IE. Strain Newman, which is phylogenetically related to USA300 strains, was not highly lethal (LD
50
of 2 × 10
9
CFUs) and was effective in causing IE. USA400 strains were both highly lethal (LD
50
s of 1 × 10
7
and 5 × 10
7
CFUs) and highly effective causes of IE. The menstrual TSS isolate FRI1169, that is TSST-1
+
, produces high-levels of α-toxin, but is not USA200, was both highly lethal and effective in causing IE. Additional studies showed that phenol soluble modulins (PSMs) produced by FRI1169 were important for sepsis but did not contribute to IE. Our studies show that these clonal groups of
S. aureus
differ in abilities to cause IE and lethal sepsis and suggest that secreted virulence factors, including SAgs and cytolysins, account for some of these differences.
Details
- Title: Subtitle
- Comparison of Staphylococcus aureus strains for ability to cause infective endocarditis and lethal sepsis in rabbits
- Creators
- Adam R Spaulding - Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa CityErin A Satterwhite - 3M Infection Prevention Division, 3M Company, St. Paul, MinneapolisYing-Chi Lin - Department of Experimental and Clinical Pharmacology, College of Pharmacy, University of Minnesota, MinneapolisOlivia N Chuang-Smith - Department of Microbiology, Medical School, University of Minnesota, MinneapolisKristi L Frank - Department of Microbiology, Medical School, University of Minnesota, MinneapolisJoseph A Merriman - Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa CityMatthew M Schaefers - Department of Experimental and Clinical Pharmacology, College of Pharmacy, University of Minnesota, MinneapolisJeremy M Yarwood - 3M Corporate Research Laboratory, 3M Company, St. Paul, MinneapolisMarnie L Peterson - Department of Experimental and Clinical Pharmacology, College of Pharmacy, University of Minnesota, MinneapolisPatrick M Schlievert - Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa City
- Resource Type
- Journal article
- Publication Details
- Frontiers in cellular and infection microbiology, Vol.2, pp.18-18
- DOI
- 10.3389/fcimb.2012.00018
- PMID
- 22919610
- PMCID
- PMC3417574
- NLM abbreviation
- Front Cell Infect Microbiol
- ISSN
- 2235-2988
- eISSN
- 2235-2988
- Publisher
- Frontiers Media S.A
- Language
- English
- Date published
- 2012
- Academic Unit
- Microbiology and Immunology; Internal Medicine
- Record Identifier
- 9984001129502771
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