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Saphylococcal toxic shock syndrome (TSS) is a life-threatening illness characterized by fever, rash, desquamation, organ dysfunction, and shock. In 1980, the use of highly absorbent tampons in the United States [...]

The bacterial toxin staphylococcal enterotoxin C2 (SEC2) can cause staphylococcal toxic shock syndrome and food poisoning. Although the previously determined crystal structure of SEC2 revealed that some histidine residues (His47, His118 and His122) contribute to the binding of zinc ions, little is known about their biological roles in SEC2. This prompted us to investigate the role of the zinc site coordinating histidine residues in the biological activities of SEC2. The mutants with substitutions at positions 118 and 122 all retained T-cell stimulatory activity, whereas the histidine mutants at position 47 were defective in the ability to stimulate T-cell proliferation. Further toxicity assays in vivo indicated that mutants SEC2-H118A and SEC2-H122A were defective in emetic and febrile activities. However, mutant SEC2-H47A could cause significant emetic and febrile responses in comparison with the other two histidine mutants. These findings suggested that the zinc-coordinating histidine residues play significant roles in superantigen and toxic activities of SEC2 and further implied that superantigen and febrile activities could be separable in staphylococcal enterotoxins. The results also show that it should be possible to design new SEC2 immunotherapeutic agents that have superantigen activity and low toxicity.

We undertook a prospective active surveillance study of invasive group A streptococcal (GAS) disease in Fiji over a 23-month period, 2005-2007. We identified 64 cases of invasive GAS disease, which [...]

Byline: Sylvie Cornelie (1), Eric Wiel (2), Niels Lund (3), Gilles Lebuffe (2), Catherine Vendeville (1), Gilles Riveau (1), Benoit Vallet (2), Elisabeth Ban (1) Keywords: Cytosine-phosphate-guanine (CpG) oligodeoxynucleotide Lipopolysaccharide (LPS) D-galactosamine Tumor necrosis factor [alpha] Septic shock Abstract: Abstract Objective. Unmethylated cytosine-phosphate-guanine (CpG) oligodeoxynucleotides are highly frequent motifs in bacterial DNA and rare in the mammalian genome. They are potent inducers of inflammatory cytokines and act synergistically with lipopolysaccharide (LPS) for the induction of tumor necrosis factor [alpha] (TNF-[alpha]) production in vivo. It has therefore been suggested that innate immune reaction to bacterial unmethylated CpG motifs might contribute to the development of septic shock. We designed this study to assess the sensitization role of CpG motifs in LPS-induced shock using the D-galactosamine (D-GalN)-sensitized mouse model. Design. A prospective, randomized in vivo animal laboratory study. Setting. Experimental research laboratory. Intervention. We performed experiments in which CpG, LPS and D-GalN were administrated sequentially in various orders or simultaneously in 8week-old BALB/c mice. Measurements and results. Cytosine-phosphate-guanine treatment potentiated LPS action only if injected prior to LPS. A combination of predefined sublethal doses of CpG (1 nmol/mouse) and LPS (1 ng/mouse) not only had a synergetic effect on TNF-[alpha] production (20.3+-9.2 IU/ml versus 2.5+-1.4 IU/ml and 5.6+-3.4 IU/ml for CpG and LPS groups, respectively, p Conclusion. Our findings indicate that CpG motifs act synergistically with LPS by initializing the synthesis of TNF-[alpha] and/or TNF-[alpha] regulating factors, thereby acting as a sensitizing agent. Author Affiliation: (1) Unite INSERM U547, Institut Pasteur de Lille, 59019 Lille Cedex,France (2) Departement d'Anesthesie-Reanimation 2, Hopital Claude Huriez, CHRU de Lille, 59037 Lille Cedex, France (3) Department of Anesthesiology, University of Rochester Medical Center, 14642 Rochester, NY, USA Article History: Received Date: 27/12/2001 Accepted Date: 12/06/2002 Article note: Electronic Publication

Key Words Staphylococcus aureus, Streptococcus pyogenes, hypotension, T cell stimulation Abstract Toxic shock syndrome (TSS) is an acute onset illness characterized by fever, rash formation, and hypotension that can lead [...]

Byline: Stefan Fronhoffs (1), Joachim Luyken (1), Kurt Steuer (2), Martin Hansis (2), Hans Vetter (1), Peter Walger (1) Keywords: Streptococcal toxic shock syndrome Capillary leak syndrome Necrotizing fasciitis C1-esterase inhibitor Abstract: Objective: To evaluate the effect of adjunctive C1-esterase inhibitor substitution therapy on clinical characteristics and outcome of patients with streptococcal toxic shock syndrome (TSS). Design: Observational. Setting: Medizinische Poliklinik, University of Bonn, Germany. Patients: Seven patients with direct or indirect evidence of streptococcal TSS. Intervention: In addition to conventional and supportive therapy, all patients received 2--3 single doses of C1-esterase inhibitor totaling 6,000--10,000 U within the first 24 h after admission. Measurements and results: All patients developed fulminant septic shock, multiorgan failure and/or capillary leak syndrome and necrotizing fasciitis within 10--72 h following the onset of first symptoms. Between 1 and 4 days following administration of C1-esterase inhibitor, a marked shift of fluid from extravascular to intravascular compartments took place in all but one patient, accompanied by a transient intra-alveolar lung edema and rapidly decreasing need for adrenergic agents. Six of seven patients survived. Conclusions: These clinical observations in a small series of patients and the favorable outcome point towards a positive effect of early and high-dose administration of C1-esterase inhibitor as adjunctive therapy in streptococcal TSS. The possible mechanism involved may be the attenuation of capillary leak syndrome (CLS) via early inactivation of complement and contact systems. Controlled studies are needed to establish an improvement of the survival rates of patients with streptococcal TSS following administration of C1-esterase inhibitor. Author Affiliation: (1) Medizinische Universitats-Poliklinik, University of Bonn, Wilhelmstrasse 35--37, 53111 Bonn, Germany (2) Universitats-Klinik und -Poliklinik fur Traumatologie und Unfallchirurgie, University of Bonn, Sigmund-Freud-Strasse 25, 53105 Bonn, Germany Article History: Received Date: 02/03/2000 Accepted Date: 03/08/2000 Article note: Final revision received: 2 August 2000 Electronic Publication

This article addresses menstrual toxic shock syndrome (TSS) from the context of it being a health threat to women of reproductive age. Results examine national suveillance data on 5,296 cases of TSS with reference to epidemiology, awareness, and monitoring of TSS., Menstrual toxic shock syndrome (TSS) emerged as a public health threat to women of reproductive age in 1979-80. We reviewed surveillance data for the period 1979 to 1996, when 5,296 [...]

A study was conducted to characterize the structures of toxic shock syndrome toxin-1 (TSST-1) mutants. Molecular replacement was carried out to determine the structures using XPLOR. The mutants were also purified by ethanol precipitation from stationary phase cultures of Staphylococcus aureus. Results showed differences in how TSST-1 and the staphylococcal enterotoxin serotype SEB bind class II major histocompatibility complexes and T-cell receptors.

The function of inducible nitric oxide synthase (iNOS) in preventing infections was determined by examining the response of mice lacking iNOS to tissue damage and shock. Wild-type mice exhibited high risk to shock and death upon exposure to bacterial endotoxic lipopolysaccharide (LPS), but iNOS mice were protected to collapse and shock. This suggests that iNOS deficiency increases risk to damage, shock and infections.

Superantigens bind to major histocompatibility complex class II molecules on antigen-presenting cells and stimulate T cells. Staphylococcus aureus enterotoxin B (SEB) and toxic shock syndrome toxin-1 (TSST-1) bind to the [...]

The three-dimensional structure of a Staphylococcus aureus superantigen, toxic shock syndrome toxin-1 (TSST-1), complexed with a human class II major histocompatibility molecule DR1), was determined by x-ray crystallography. The TSST-1 [...]

A study was done on the distinct binding sites on HLA-DR for invariant chain and staphylococcal enterotoxins. It was shown that staphylococcal enterotoxins A to E and exfoliative toxin bind to cells expressing the alphabetaIi complex at levels similar to cells expressing only alphabeta chains at the cell surface. Ii inhibits the binding of toxic shock syndrome toxin and the subsequent stimulation of T cells.