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Zhu Z, Hu Z, Li S, Fang R, Ono HK, Hu DL. Molecular Characteristics and Pathogenicity of Staphylococcus aureus Exotoxins. Int J Mol Sci 2023; 25:395. [PMID: 38203566 PMCID: PMC10778951 DOI: 10.3390/ijms25010395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 12/24/2023] [Accepted: 12/26/2023] [Indexed: 01/12/2024] Open
Abstract
Staphylococcus aureus stands as one of the most pervasive pathogens given its morbidity and mortality worldwide due to its roles as an infectious agent that causes a wide variety of diseases ranging from moderately severe skin infections to fatal pneumonia and sepsis. S. aureus produces a variety of exotoxins that serve as important virulence factors in S. aureus-related infectious diseases and food poisoning in both humans and animals. For example, staphylococcal enterotoxins (SEs) produced by S. aureus induce staphylococcal foodborne poisoning; toxic shock syndrome toxin-1 (TSST-1), as a typical superantigen, induces toxic shock syndrome; hemolysins induce cell damage in erythrocytes and leukocytes; and exfoliative toxin induces staphylococcal skin scalded syndrome. Recently, Panton-Valentine leucocidin, a cytotoxin produced by community-associated methicillin-resistant S. aureus (CA-MRSA), has been reported, and new types of SEs and staphylococcal enterotoxin-like toxins (SEls) were discovered and reported successively. This review addresses the progress of and novel insights into the molecular structure, biological activities, and pathogenicity of both the classic and the newly identified exotoxins produced by S. aureus.
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Affiliation(s)
- Zhihao Zhu
- Department of Zoonoses, Kitasato University School of Veterinary Medicine, Towada 034-8628, Japan; (Z.Z.); (Z.H.); (H.K.O.)
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China;
| | - Zuo Hu
- Department of Zoonoses, Kitasato University School of Veterinary Medicine, Towada 034-8628, Japan; (Z.Z.); (Z.H.); (H.K.O.)
| | - Shaowen Li
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China;
| | - Rendong Fang
- Joint International Research Laboratory of Animal Health and Animal Food Safety, College of Veterinary Medicine, Southwest University, Chongqing 400715, China;
| | - Hisaya K. Ono
- Department of Zoonoses, Kitasato University School of Veterinary Medicine, Towada 034-8628, Japan; (Z.Z.); (Z.H.); (H.K.O.)
| | - Dong-Liang Hu
- Department of Zoonoses, Kitasato University School of Veterinary Medicine, Towada 034-8628, Japan; (Z.Z.); (Z.H.); (H.K.O.)
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Targeted Proteomics Analysis of Staphylococcal Superantigenic Toxins in Menstrual Fluid from Women with Menstrual Toxic Shock Syndrome (mTSS). Toxins (Basel) 2022; 14:toxins14120886. [PMID: 36548783 PMCID: PMC9788610 DOI: 10.3390/toxins14120886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Revised: 11/23/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
Menstrual toxic shock syndrome (mTSS) is a rare life-threatening febrile illness that occurs in women using intravaginal menstrual protection. It is caused by toxic shock syndrome toxin 1 (TSST-1) produced by Staphylococcus aureus, triggering a sudden onset of rash and hypotension, subsequently leading to multiple organ failure. Detecting TSST-1 and S. aureus virulence factors in menstrual fluid could accelerate the diagnosis and improve therapeutic management of mTSS. However, menstrual fluid is a highly complex matrix, making detection of bacterial toxins challenging. Here, we present a mass-spectrometry-based proteomics workflow for the targeted, quantitative analysis of four S. aureus superantigenic toxins in menstrual fluids (TSST-1, SEA, SEC, and SED). This method was applied to characterize toxin levels in menstrual fluids collected from patients with mTSS and healthy women. Toxins were detectable in samples from patients with mTSS and one healthy donor at concentrations ranging from 0 to 0.46 µg/mL for TSST-1, and 0 to 1.07 µg/mL for SEC. SEA and SED were never detected in clinical specimens, even though many S. aureus strains were positive for the corresponding genes. The method presented here could be used to explore toxin production in vivo in users of intravaginal devices to improve the diagnosis, understanding, and prevention of mTSS.
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Lutz MB, Backer RA, Clausen BE. Revisiting Current Concepts on the Tolerogenicity of Steady-State Dendritic Cell Subsets and Their Maturation Stages. THE JOURNAL OF IMMUNOLOGY 2021; 206:1681-1689. [PMID: 33820829 DOI: 10.4049/jimmunol.2001315] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 01/11/2021] [Indexed: 12/25/2022]
Abstract
The original concept stated that immature dendritic cells (DC) act tolerogenically whereas mature DC behave strictly immunogenically. Meanwhile, it is also accepted that phenotypically mature stages of all conventional DC subsets can promote tolerance as steady-state migratory DC by transporting self-antigens to lymph nodes to exert unique functions on regulatory T cells. We propose that in vivo 1) there is little evidence for a tolerogenic function of immature DC during steady state such as CD4 T cell anergy induction, 2) all tolerance as steady-state migratory DC undergo common as well as subset-specific molecular changes, and 3) these changes differ by quantitative and qualitative markers from immunogenic DC, which allows one to clearly distinguish tolerogenic from immunogenic migratory DC.
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Affiliation(s)
- Manfred B Lutz
- Institute for Virology and Immunobiology, University of Würzburg, 97070 Würzburg, Germany; and
| | - Ronald A Backer
- Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg-University Mainz, 55122 Mainz, Germany
| | - Björn E Clausen
- Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg-University Mainz, 55122 Mainz, Germany
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Belen SM, Sofía NT, Romina M, Belén AM, Santiago C, María Julieta FL, Pablo R, Cristina V, Martín D, Mauricio DM, Emilio M, Marisa F. Optimized surface plasmon resonance immunoassay for staphylococcal enterotoxin G detection using silica nanoparticles. Biochem Biophys Res Commun 2021; 558:168-174. [PMID: 33932776 DOI: 10.1016/j.bbrc.2021.04.077] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 04/19/2021] [Indexed: 10/21/2022]
Abstract
Staphylococcal enterotoxins are one of the most important causative agents of food poisoning. These molecules function as both gastrointestinal toxins and superantigens (SAgs) which can simultaneously bind MHC-II and T cell receptor leading to a non-specific polyclonal T cell activation and massive proinflammatory cytokine release. Common symptoms include vomiting and diarrhea; however, in more severe cases, systemic dissemination may result in toxic shock syndrome and can be lethal in a few hours. Only small amounts of these heat-stable toxins are needed to cause the disease. Therefore, it is highly important to detect quickly low concentrations of SAgs in biological samples. In this work, we report a surface plasmon resonance (SPR)-based capture immunoassay for the detection of the SAg SEG. We analyzed the use of different amplification strategies. The SPR-based double-antibody sandwich approach could detect picomolar levels of SEG. The use of antibody-coated silica nanoparticles (AbSiNPs) as an alternative enhancing reagent also detected SEG in the picomolar range. Although AbSiNPs did not improve the limit of detection, for the same amount of SAg tested, AbSiNPs gave a higher response level than free antibodies. This work highlights the suitability of silica nanoparticles for signal amplification in SPR-based biosensors. Overall, SPR biosensors offer the capability for continuous real-time monitoring and high sensitivity that can be befitting for the detection of enterotoxins in food industries, laboratories and regulatory agencies.
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Affiliation(s)
- Sarratea Maria Belen
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
| | - Noli Truant Sofía
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
| | - Mitarotonda Romina
- Universidad Nacional de Luján, Departamento de Ciencias Básicas, Luján, Argentina; Universidad Nacional de Luján, Instituto de Ecología y Desarrollo Sustentable (INEDES)-CONICET, Laboratorio de Inmunología, Buenos Aires, Argentina
| | - Antonoglou María Belén
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
| | - Chiappini Santiago
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
| | - Fernández Lynch María Julieta
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
| | - Romasanta Pablo
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
| | - Vescina Cristina
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Química Analítica, Buenos Aires, Argentina
| | - Desimone Martín
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de la Química y Metabolismo del Fármaco (IQUIMEFA), Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
| | - De Marzi Mauricio
- Universidad Nacional de Luján, Departamento de Ciencias Básicas, Luján, Argentina; Universidad Nacional de Luján, Instituto de Ecología y Desarrollo Sustentable (INEDES)-CONICET, Laboratorio de Inmunología, Buenos Aires, Argentina
| | - Malchiodi Emilio
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
| | - Fernández Marisa
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina.
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Fries-Craft K, Meyer MM, Sato Y, El-Gazzar M, Bobeck EA. Age and Staphylococcus aureus Inoculation Route Differentially Alter Metabolic Potential and Immune Cell Populations in Laying Hens. Front Vet Sci 2021; 8:653129. [PMID: 33842579 PMCID: PMC8032939 DOI: 10.3389/fvets.2021.653129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 03/03/2021] [Indexed: 01/13/2023] Open
Abstract
In 2018 and 2019, Staphylococcus aureus was isolated from multiple post-molt commercial laying hens with unusually high mortality. A challenge study was conducted to elucidate the role of S. aureus in this disease outbreak and the work herein represents the assessment of immunological responses in laying hens experimentally infected with S. aureus isolates from these cases. A total of 200 laying hens at 22 or 96 weeks of age (100/ age group) were assigned to 1 of 4 experimental inoculation groups (negative control, oral gavage, subcutaneous injection, or intravenous injection) after a 72 h acclimation period. Blood samples were taken prior to inoculation (baseline), 6 h post-inoculation (pi), 24 hpi, 3 dpi, and 7 dpi. Additional spleen samples to further assess systemic immunity were taken at baseline, 3 and 8 dpi. Metabolic phenotypes of peripheral blood mononuclear cells (PBMC) were isolated and assessed by Seahorse metabolic assay. Immune cell profiles in the spleen and PBMC were assessed by multicolor flow cytometry. At baseline, 96-week-old laying hens had 26.7% fewer PBMC-derived T cells compared to 22-week-old birds. Older hens had 28.9% increased helper T cell (TH) populations and 60.5% reduced γδ T cells (P = 0.03 and < 0.0001) which may contribute to variable clinical responses between age groups; however, no age-related differences in metabolic potential were observed. Metabolic outcomes showed that birds remained stressed from transport and re-housing past a 72 h acclimation period and through 24 h- 3 days post-inoculation. Inoculation with S. aureus generally reduced oxidative and glycolytic potentials compared to the control, with the greatest reductions observed in birds inoculated by intravenous injection (P < 0.05). Overall CD3+ T cell populations showed significant reductions in the intravenous group compared to other inoculation routes from 24 hpi to 7 dpi (23.6–39.0%; P ≤ 0.0001). These results suggest that age-related baseline differences in T cell populations and changes to T cell subpopulations and other immune cells due to inoculation route may have an additive effect on S. aureus- induced reductions in metabolic potential; however, further research linking metabolic potential and immune cell profiles is needed.
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Affiliation(s)
- Krysten Fries-Craft
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Meaghan M Meyer
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Yuko Sato
- Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, United States
| | - Mohamed El-Gazzar
- Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, United States
| | - Elizabeth A Bobeck
- Department of Animal Science, Iowa State University, Ames, IA, United States
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Van der Sluis RM, Kumar NA, Pascoe RD, Zerbato JM, Evans VA, Dantanarayana AI, Anderson JL, Sékaly RP, Fromentin R, Chomont N, Cameron PU, Lewin SR. Combination Immune Checkpoint Blockade to Reverse HIV Latency. THE JOURNAL OF IMMUNOLOGY 2020; 204:1242-1254. [PMID: 31988180 DOI: 10.4049/jimmunol.1901191] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 12/18/2019] [Indexed: 12/11/2022]
Abstract
In people living with HIV on antiretroviral therapy, HIV latency is the major barrier to a cure. HIV persists preferentially in CD4+ T cells expressing multiple immune checkpoint (IC) molecules, including programmed death (PD)-1, T cell Ig and mucin domain-containing protein 3 (TIM-3), lymphocyte associated gene 3 (LAG-3), and T cell immunoreceptor with Ig and ITIM domains (TIGIT). We aimed to determine whether these and other IC molecules have a functional role in maintaining HIV latency and whether blocking IC molecules with Abs reverses HIV latency. Using an in vitro model that establishes latency in both nonproliferating and proliferating human CD4+ T cells, we show that proliferating cells express multiple IC molecules at high levels. Latent infection was enriched in proliferating cells expressing PD-1. In contrast, nonproliferating cells expressed IC molecules at significantly lower levels, but latent infection was enriched in cells expressing PD-1, TIM-3, CTL-associated protein 4 (CTLA-4), or B and T lymphocyte attenuator (BTLA). In the presence of an additional T cell-activating stimulus, staphylococcal enterotoxin B, Abs to CTLA-4 and PD-1 reversed HIV latency in proliferating and nonproliferating CD4+ T cells, respectively. In the absence of staphylococcal enterotoxin B, only the combination of Abs to PD-1, CTLA-4, TIM-3, and TIGIT reversed latency. The potency of latency reversal was significantly higher following combination IC blockade compared with other latency-reversing agents, including vorinostat and bryostatin. Combination IC blockade should be further explored as a strategy to reverse HIV latency.
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Affiliation(s)
- Renée M Van der Sluis
- The Peter Doherty Institute for Infection and Immunity, The University of Melbourne and Royal Melbourne Hospital, Melbourne, Victoria 3000, Australia
| | - Nitasha A Kumar
- The Peter Doherty Institute for Infection and Immunity, The University of Melbourne and Royal Melbourne Hospital, Melbourne, Victoria 3000, Australia
| | - Rachel D Pascoe
- The Peter Doherty Institute for Infection and Immunity, The University of Melbourne and Royal Melbourne Hospital, Melbourne, Victoria 3000, Australia
| | - Jennifer M Zerbato
- The Peter Doherty Institute for Infection and Immunity, The University of Melbourne and Royal Melbourne Hospital, Melbourne, Victoria 3000, Australia
| | - Vanessa A Evans
- The Peter Doherty Institute for Infection and Immunity, The University of Melbourne and Royal Melbourne Hospital, Melbourne, Victoria 3000, Australia
| | - Ashanti I Dantanarayana
- The Peter Doherty Institute for Infection and Immunity, The University of Melbourne and Royal Melbourne Hospital, Melbourne, Victoria 3000, Australia
| | - Jenny L Anderson
- The Peter Doherty Institute for Infection and Immunity, The University of Melbourne and Royal Melbourne Hospital, Melbourne, Victoria 3000, Australia
| | | | - Rémi Fromentin
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montreal, Quebec H2X 3E4, Canada
| | - Nicolas Chomont
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montreal, Quebec H2X 3E4, Canada.,Department of Microbiology, Infectiology and Immunology, Faculty of Medicine, Université de Montréal, Montreal, Quebec H3T 1J4, Canada; and
| | - Paul U Cameron
- The Peter Doherty Institute for Infection and Immunity, The University of Melbourne and Royal Melbourne Hospital, Melbourne, Victoria 3000, Australia.,Department of Infectious Diseases, Monash University and the Alfred Hospital, Melbourne, Victoria 3000, Australia
| | - Sharon R Lewin
- The Peter Doherty Institute for Infection and Immunity, The University of Melbourne and Royal Melbourne Hospital, Melbourne, Victoria 3000, Australia; .,Department of Infectious Diseases, Monash University and the Alfred Hospital, Melbourne, Victoria 3000, Australia
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Radcliff FJ, Waldvogel-Thurlow S, Clow F, Mahadevan M, Johnston J, Li G, Proft T, Douglas RG, Fraser JD. Impact of Superantigen-Producing Bacteria on T Cells from Tonsillar Hyperplasia. Pathogens 2019; 8:pathogens8030090. [PMID: 31252586 PMCID: PMC6789895 DOI: 10.3390/pathogens8030090] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 06/23/2019] [Accepted: 06/24/2019] [Indexed: 02/07/2023] Open
Abstract
Staphylococcus aureus and Group A Streptococcus (GAS) are common occupants of the tonsils and many strains produce potent exotoxins (mitogens) that directly target T cells, which could be a driver for tonsillar hyperplasia. Tonsil tissues from 41 patients were tested for these bacteria in conjunction with profiling of B and T cells by flow cytometry. S. aureus and GAS were detected in tonsil tissue from 44% and 7%, respectively, of patients by bacteriological culture; immuno-histology showed bacteria in close proximity to both B and T lymphocytes. The presence of tonsillar S. aureus did not alter B or T cell populations, whereas peripheral blood mucosal-associated invariant T (MAIT) cells were significantly increased in S. aureus culture positive individuals (p < 0.006). Alterations of tonsil CD4+ TCR Vβ family members relative to peripheral blood were evident in 29 patients. Three patients had strong TCR Vβ skewing indicative of recent exposure to superantigens, their tonsils contained mitogenic bacteria, and supernatants from these bacteria were used to partially recapitulate the skewing profile in vitro, supporting the notion that superantigens can target tonsillar T cells in situ. Tonsils are a reservoir for superantigen-producing bacteria with the capacity to alter the composition and function of key immune cells.
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Affiliation(s)
- Fiona J Radcliff
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland 1023, New Zealand.
| | | | - Fiona Clow
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland 1023, New Zealand
| | - Murali Mahadevan
- Department of Surgery, University of Auckland, Auckland 1023, New Zealand
| | - James Johnston
- Department of Surgery, University of Auckland, Auckland 1023, New Zealand
| | - Gen Li
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland 1023, New Zealand
| | - Thomas Proft
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland 1023, New Zealand
| | - Richard G Douglas
- Department of Surgery, University of Auckland, Auckland 1023, New Zealand
| | - John D Fraser
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland 1023, New Zealand
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Staphylococcal Superantigens: Pyrogenic Toxins Induce Toxic Shock. Toxins (Basel) 2019; 11:toxins11030178. [PMID: 30909619 PMCID: PMC6468478 DOI: 10.3390/toxins11030178] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 03/18/2019] [Accepted: 03/20/2019] [Indexed: 01/01/2023] Open
Abstract
Staphylococcal enterotoxin B (SEB) and related superantigenic toxins produced by Staphylococcus aureus are potent activators of the immune system. These protein toxins bind to major histocompatibility complex (MHC) class II molecules and specific Vβ regions of T-cell receptors (TCRs), resulting in the activation of both monocytes/macrophages and T lymphocytes. The bridging of TCRs with MHC class II molecules by superantigens triggers an early “cytokine storm” and massive polyclonal T-cell proliferation. Proinflammatory cytokines, tumor necrosis factor α, interleukin 1 (IL-1), IL-2, interferon γ (IFNγ), and macrophage chemoattractant protein 1 elicit fever, inflammation, multiple organ injury, hypotension, and lethal shock. Upon MHC/TCR ligation, superantigens induce signaling pathways, including mitogen-activated protein kinase cascades and cytokine receptor signaling, which results in NFκB activation and the phosphoinositide 3-kinase/mammalian target of rapamycin pathways. In addition, gene profiling studies have revealed the essential roles of innate antimicrobial defense genes in the pathogenesis of SEB. The genes expressed in a murine model of SEB-induced shock include intracellular DNA/RNA sensors, apoptosis/DNA damage-related molecules, endoplasmic reticulum/mitochondrial stress responses, immunoproteasome components, and IFN-stimulated genes. This review focuses on the signaling pathways induced by superantigens that lead to the activation of inflammation and damage response genes. The induction of these damage response genes provides evidence that SEB induces danger signals in host cells, resulting in multiorgan injury and toxic shock. Therapeutics targeting both host inflammatory and cell death pathways can potentially mitigate the toxic effects of staphylococcal superantigens.
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Schmitz M, Roux X, Huttner B, Pugin J. Streptococcal toxic shock syndrome in the intensive care unit. Ann Intensive Care 2018; 8:88. [PMID: 30225523 PMCID: PMC6141408 DOI: 10.1186/s13613-018-0438-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 09/11/2018] [Indexed: 11/10/2022] Open
Abstract
The streptococcal toxic shock syndrome is a severe complication associated with invasive infections by group A streptococci. In spite of medical progresses in the care of patients with septic shock during the last decades, this condition has remained associated with a high mortality. Early recognition and multidisciplinary management are key to the care of patients with streptococcal toxic shock syndrome, with intensive and appropriate intensive support of failing organs, rapid diagnosis of infectious source(s), and surgical management. The epidemiology and risk factors for streptococcal toxic shock syndrome remain to be better studied, including the possible causal role of exposure to nonsteroidal anti-inflammatory drugs. In this review article, the authors review the current knowledge of streptococcal toxic shock syndrome and discuss the pathophysiology as well as its supportive and specific treatment.
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Affiliation(s)
- Marylin Schmitz
- Division of Intensive Care, Faculty of Medicine Geneva, University Hospitals of Geneva, University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14, Switzerland
| | - Xavier Roux
- Division of Intensive Care, Faculty of Medicine Geneva, University Hospitals of Geneva, University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14, Switzerland
| | - Benedikt Huttner
- Division of Infectious Diseases, Faculty of Medicine Geneva, University Hospitals of Geneva, University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14, Switzerland
| | - Jérôme Pugin
- Division of Intensive Care, Faculty of Medicine Geneva, University Hospitals of Geneva, University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14, Switzerland
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Maina IW, Patel NN, Cohen NA. Understanding the Role of Biofilms and Superantigens in Chronic Rhinosinusitis. CURRENT OTORHINOLARYNGOLOGY REPORTS 2018; 6:253-262. [PMID: 30859016 PMCID: PMC6407876 DOI: 10.1007/s40136-018-0212-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE OF REVIEW This review explores recent discoveries in our understanding of how biofilms and superantigens contribute to the pathogenesis of chronic rhinosinusitis (CRS). It also examines clinical implications and novel treatment approaches for biofilm associated CRS. RECENT FINDINGS While the role of biofilms in CRS has been studied for 14 years, research interest has now turned toward elucidating new methods of biofilm detection, microbial diversity, and novel treatment approaches. Recent studies on biofilm superantigens aim to clarify the immunological mechanisms of upper airway inflammation, particularly the type-2 response seen in nasal polyposis. SUMMARY Biofilms are a topic of research interest for their role in the pathogenesis of chronic rhinosinusitis, particularly when they elute superantigens. New studies on this topic focus on the molecular and cellular mechanisms at play.
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Affiliation(s)
- Ivy W Maina
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
- Philadelphia Veterans Affairs Medical Center, Philadelphia, PA
| | - Neil N Patel
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
- Philadelphia Veterans Affairs Medical Center, Philadelphia, PA
| | - Noam A Cohen
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
- Philadelphia Veterans Affairs Medical Center, Philadelphia, PA
- Monell Chemical Senses Center, Philadelphia, PA
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11
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Detección y expresión de superantígenos y de resistencia antimicrobiana en aislamientos obtenidos de mujeres portadoras de Staphylococcus aureus que cuidan y alimentan niños. BIOMEDICA 2018; 38:96-104. [PMID: 29676866 DOI: 10.7705/biomedica.v38i0.3653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 05/10/2017] [Indexed: 11/21/2022]
Abstract
Introducción. Staphylococcus aureus coloniza mucosas y piel, y causa graves infecciones en el hombre y los animales. Es importante establecer el estatus de portadoras de cepas enterotoxigénicas de este microorganismo en manipuladoras de alimentos, con el fin de prevenir intoxicaciones alimentarias.Objetivo. Establecer las correlaciones entre los genes de enterotoxinas clásicas, el gen tsst-1, la producción de toxinas en cultivo y la resistencia antimicrobiana en aislamientos de S. aureus provenientes de manipuladoras de alimentos que cuidan niños en sus comunidades.Materiales y métodos. Se cultivaron muestras de las fosas nasales y las yemas de los dedos de las manos, y se identificó S. aureus empleando las pruebas de rutina y métodos automatizados. La extracción de ADN se hizo mediante el método de bromuro de cetil-trimetil-amonio (Cetyl-Trimethyl-Ammonium Bromide, CTAB) modificado. Para la detección de superantígenos se emplearon pruebas de reacción en cadena de la polimerasa (PCR) simple y múltiple, y para la de toxinas, estuches comerciales.Resultados. Se encontró que el 22,0 % de los aislamientos correspondía a portadoras de S. aureus: 17,0 % en los aislamientos de fosas nasales; 5,0 % en los de las manos y 6,7 % simultáneamente en los dos sitios. La prevalencia de superantígenos fue de 73,7 %. El genotipo más frecuente fue el seatsst-1, con 10,0 %. La resistencia a un solo antibiótico fue de 74,7 % y, a cuatro antibióticos, de 3,2 %; de los aislamientos, el 93,7 % correspondía a cepas productoras de betalactamasas. La detección de genes clásicos y de tsst-1 mediante PCR fue de 48,4 % y la de toxinas en el sobrenadante, de 42,1 %,con una correlación de 95,7 %. Las mayores correlaciones se establecieron entre las toxinas TSST-1 (22/22) y SEA (17/18). La correlación del gen tsst-1 con la proteína y la resistencia fue de 100 %. Todos los aislamientos con el genotipo sea-tsst-1 t fueron resistentes y productores de las toxinas.Conclusión. La tasa de aislamientos de S. aureus toxigénicos y resistentes obtenidos de mujeres que cuidan y preparan alimentos para niños fue de más de 70 %, lo que demostró su gran virulencia y la consecuente necesidad de aplicar estrictamente las normas higiénicas y sanitarias vigentes para evitar el riesgo de intoxicación alimentaria.
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Javouhey E, Bolze PA, Jamen C, Lina G, Badiou C, Poyart C, Portefaix A, Tristan A, Laurent F, Bes M, Vandenesch F, Gilletand Y, Dauwalder O. Similarities and Differences Between Staphylococcal and Streptococcal Toxic Shock Syndromes in Children: Results From a 30-Case Cohort. Front Pediatr 2018; 6:360. [PMID: 30547021 PMCID: PMC6280580 DOI: 10.3389/fped.2018.00360] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 11/05/2018] [Indexed: 11/24/2022] Open
Abstract
Introduction: Toxic shock syndromes (TSS) are severe shocks due to staphylococcal or streptococcal infection that require specific treatments. The early recognition of these shocks is crucial to improve their outcomes. Objectives: The primary objective of this study was to compare characteristics and outcomes of staphylococcal and streptococcal TSS in children, in order to identify putative early clinical diagnostic criteria. Secondary objectives were to determine the toxin gene profiles of associated isolated strains and the relevance of measuring Vβ T-cell signatures to confirm the diagnosis. Study design: We performed a multicenter retrospective evaluation of clinical data, biological results, and treatment outcomes of children with a confirmed or probable case of staphylococcal or streptococcal TSS. Children were consecutively included if they were admitted to the pediatric intensive care units of Lyon (France), between January 2005 and July 2011. Results: Among the 30 analyzed children, 15 presented staphylococcal TSS and 15 streptococcal TSS. The most frequent origin of staphylococcal and streptococcal TSS was the lower respiratory tract (53%) and the genital tract (47%) respectively. Non-menstrual TSS syndrome cases presented more frequently with neurological alterations, and digestive signs were predominant in menstrual forms. Compared to Staphylococcal TSS, Streptococcal TSS presented with higher organ dysfunction scores (median Pediatric Index of Mortality 2 score 20.9 (4.1-100) vs. 1.7 (1.3-2.3), p = 0.001), required respiratory support more frequently (80 vs. 33%, p = 0.02), were intubated for a longer time (3 days (0.75-5) vs. 1 day (0-1.5), p = 0.006) and had a non-significant trend of higher, case-fatality rate (20 vs. 7%, p = 0.60). The lack of antitoxin therapy was associated with higher case-fatality rate (50 vs. 4%, p = 0.04). The Vβ repertoire measurements exhibited toxin dependent-alterations in accordance with the toxin gene profiles of isolated strains in both types of toxic shock syndromes. Regarding toxin gene profiles of isolated strains, 10/15 Staphylococcus aureus belonged to clonal complex (CC) 30 and 6/12 Streptococcus pyogenes were emm1 type suggesting clonal etiologies for both staphylococcal and streptococcal TSS. Conclusion: Despite the involvement of functionally similar toxins, staphylococcal and streptococcal TSS differed by their clinical signs, origin of infection and prognosis. The detection of Vβ profiles was useful to confirm the diagnosis of staphylococcal and streptococcal TSS and for the identification of involved toxins.
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Affiliation(s)
- Etienne Javouhey
- Pediatric Emergency and Critical Care Unit, Hospices Civils de Lyon, Hôpital Femme Mère Enfant, Bron, France.,Faculté de Médecine Lyon Est, Université de Lyon, Domaine de la Buire, Lyon, France
| | - Pierre-Adrien Bolze
- Service de Gynécologie et Obstétrique, Hospices Civils de Lyon, Hôpital Femme Mère Enfant, Bron, France
| | - Claire Jamen
- Pediatric Emergency and Critical Care Unit, Hospices Civils de Lyon, Hôpital Femme Mère Enfant, Bron, France
| | - Gerard Lina
- Centre National de Référence des Staphylocoques, Institut des Agents Infectieux, Centre de Biologie et de Pathologie Nord, Hospices Civils de Lyon, Lyon, France.,Laboratoire de Bactériologie, Centre de Biologie et de Pathologie Nord, Institut des Agents Infectieux, Hospices Civils de Lyon, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Lyon 1, Ecole Normale Supérieure de Lyon, CNRS UMR5308, Lyon, France
| | - Cédric Badiou
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Lyon 1, Ecole Normale Supérieure de Lyon, CNRS UMR5308, Lyon, France
| | - Claire Poyart
- Centre National de Références des Streptocoques - Groupe Hospitalier Paris Centre Cochin-Hôtel Dieu-Broca, Assistance Publique Hôpitaux de Paris, Paris, France.,Institut Cochin Université Sorbonne Paris Descartes, Paris, France.,INSERM 1016, Institut Cochin, Paris, France.,CNRS, UMR8104, Institut Cochin, Paris, France
| | - Aurelie Portefaix
- Pediatric Emergency and Critical Care Unit, Hospices Civils de Lyon, Hôpital Femme Mère Enfant, Bron, France.,EPICIME-CIC 1407 de Lyon, Inserm, Service de Pharmacotoxicologie, Hospices Civils de Lyon, Bron, France
| | - Anne Tristan
- Faculté de Médecine Lyon Est, Université de Lyon, Domaine de la Buire, Lyon, France.,Centre National de Référence des Staphylocoques, Institut des Agents Infectieux, Centre de Biologie et de Pathologie Nord, Hospices Civils de Lyon, Lyon, France.,Laboratoire de Bactériologie, Centre de Biologie et de Pathologie Nord, Institut des Agents Infectieux, Hospices Civils de Lyon, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Lyon 1, Ecole Normale Supérieure de Lyon, CNRS UMR5308, Lyon, France
| | - Frédéric Laurent
- Faculté de Médecine Lyon Est, Université de Lyon, Domaine de la Buire, Lyon, France.,Centre National de Référence des Staphylocoques, Institut des Agents Infectieux, Centre de Biologie et de Pathologie Nord, Hospices Civils de Lyon, Lyon, France.,Laboratoire de Bactériologie, Centre de Biologie et de Pathologie Nord, Institut des Agents Infectieux, Hospices Civils de Lyon, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Lyon 1, Ecole Normale Supérieure de Lyon, CNRS UMR5308, Lyon, France
| | - Michèle Bes
- Centre National de Référence des Staphylocoques, Institut des Agents Infectieux, Centre de Biologie et de Pathologie Nord, Hospices Civils de Lyon, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Lyon 1, Ecole Normale Supérieure de Lyon, CNRS UMR5308, Lyon, France
| | - François Vandenesch
- Faculté de Médecine Lyon Est, Université de Lyon, Domaine de la Buire, Lyon, France.,Centre National de Référence des Staphylocoques, Institut des Agents Infectieux, Centre de Biologie et de Pathologie Nord, Hospices Civils de Lyon, Lyon, France.,Laboratoire de Bactériologie, Centre de Biologie et de Pathologie Nord, Institut des Agents Infectieux, Hospices Civils de Lyon, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Lyon 1, Ecole Normale Supérieure de Lyon, CNRS UMR5308, Lyon, France
| | - Yves Gilletand
- Pediatric Emergency and Critical Care Unit, Hospices Civils de Lyon, Hôpital Femme Mère Enfant, Bron, France.,Centre National de Référence des Staphylocoques, Institut des Agents Infectieux, Centre de Biologie et de Pathologie Nord, Hospices Civils de Lyon, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Lyon 1, Ecole Normale Supérieure de Lyon, CNRS UMR5308, Lyon, France
| | - Olivier Dauwalder
- Centre National de Référence des Staphylocoques, Institut des Agents Infectieux, Centre de Biologie et de Pathologie Nord, Hospices Civils de Lyon, Lyon, France.,Laboratoire de Bactériologie, Centre de Biologie et de Pathologie Nord, Institut des Agents Infectieux, Hospices Civils de Lyon, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Lyon 1, Ecole Normale Supérieure de Lyon, CNRS UMR5308, Lyon, France
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Stentzel S, Gläser R, Bröker BM. Elucidating the anti-Staphylococcus aureusantibody response by immunoproteomics. Proteomics Clin Appl 2016; 10:1011-1019. [DOI: 10.1002/prca.201600050] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 06/20/2016] [Accepted: 08/08/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Sebastian Stentzel
- Department of Immunology; University Medicine Greifswald; Greifswald Germany
| | - Regine Gläser
- Department of Dermatology; University Hospital Schleswig-Holstein; Kiel Germany
| | - Barbara M. Bröker
- Department of Immunology; University Medicine Greifswald; Greifswald Germany
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Yokochi T, Sakanishi S, Ishidou Y, Kawano G, Matsuishi T, Akita Y, Obu K. Acute encephalopathy with biphasic seizures and late reduced diffusion associated with staphylococcal toxic shock syndrome caused by burns. Brain Dev 2016; 38:875-9. [PMID: 27117386 DOI: 10.1016/j.braindev.2016.04.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 04/05/2016] [Accepted: 04/07/2016] [Indexed: 01/19/2023]
Abstract
We report a case of acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) associated with toxic shock syndrome caused by burns. A one-year-old girl was admitted to our hospital for treatment of severe burns. On day 3, she exhibited a fever, generalized rash and multiple organ failure. She was diagnosed with toxic shock syndrome after burns. She had seizures with fever twice on the same day, followed by secondary seizures on day 8 and transient deterioration of the gross motor functions involved in sitting alone and rolling over. On day 9, MRI diffusion-weighted images showed bright tree appearance (BTA). We conclude that she developed AESD.
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Affiliation(s)
- Takaoki Yokochi
- Department of Pediatrics, St Mary's Hospital, Fukuoka, Japan
| | | | - Yuuki Ishidou
- Department of Pediatrics, St Mary's Hospital, Fukuoka, Japan
| | - Go Kawano
- Department of Pediatrics, St Mary's Hospital, Fukuoka, Japan
| | | | - Yukihiro Akita
- Department of Pediatrics, St Mary's Hospital, Fukuoka, Japan
| | - Keizo Obu
- Department of Pediatrics, St Mary's Hospital, Fukuoka, Japan
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Schwameis M, Roppenser B, Firbas C, Gruener CS, Model N, Stich N, Roetzer A, Buchtele N, Jilma B, Eibl MM. Safety, tolerability, and immunogenicity of a recombinant toxic shock syndrome toxin (rTSST)-1 variant vaccine: a randomised, double-blind, adjuvant-controlled, dose escalation first-in-man trial. THE LANCET. INFECTIOUS DISEASES 2016; 16:1036-1044. [DOI: 10.1016/s1473-3099(16)30115-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 05/11/2016] [Accepted: 05/11/2016] [Indexed: 01/04/2023]
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Opportunities for the development of novel therapies based on host-microbial interactions. Pharmacol Res 2016; 112:68-83. [PMID: 27107789 DOI: 10.1016/j.phrs.2016.04.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 04/07/2016] [Accepted: 04/08/2016] [Indexed: 12/21/2022]
Abstract
Immune responses are fundamental for protecting against most infectious agents. However, there is now much evidence to suggest that the pathogenesis and tissue damage after infection are not usually related to the direct action of the replication of microorganisms, but instead to altered immune responses triggered after the contact with the pathogen. This review article discusses several mechanisms necessary for the host to protect against microbial infection and focuses in aspects that cause altered inflammation and drive immunopathology. These basic findings can ultimately reveal pathways amenable to host-directed therapy in adjunct to antimicrobial therapy for future improved control measures for many infectious diseases. Therefore, modulating the effects of inflammatory pathways may represent a new therapy during infection outcome and disease.
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Thammavongsa V, Kim HK, Missiakas D, Schneewind O. Staphylococcal manipulation of host immune responses. Nat Rev Microbiol 2015; 13:529-43. [PMID: 26272408 DOI: 10.1038/nrmicro3521] [Citation(s) in RCA: 368] [Impact Index Per Article: 40.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Staphylococcus aureus, a bacterial commensal of the human nares and skin, is a frequent cause of soft tissue and bloodstream infections. A hallmark of staphylococcal infections is their frequent recurrence, even when treated with antibiotics and surgical intervention, which demonstrates the bacterium's ability to manipulate innate and adaptive immune responses. In this Review, we highlight how S. aureus virulence factors inhibit complement activation, block and destroy phagocytic cells and modify host B cell and T cell responses, and we discuss how these insights might be useful for the development of novel therapies against infections with antibiotic resistant strains such as methicillin-resistant S. aureus.
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Affiliation(s)
- Vilasack Thammavongsa
- 1] Department of Microbiology, University of Chicago, 920 East 58th Street, Chicago, Illinois 60637, USA. [2] Regeneron Pharmaceuticals, 755 Old Saw Mill River Road, Tarrytown, New York 10591, USA
| | - Hwan Keun Kim
- Department of Microbiology, University of Chicago, 920 East 58th Street, Chicago, Illinois 60637, USA
| | - Dominique Missiakas
- Department of Microbiology, University of Chicago, 920 East 58th Street, Chicago, Illinois 60637, USA
| | - Olaf Schneewind
- Department of Microbiology, University of Chicago, 920 East 58th Street, Chicago, Illinois 60637, USA
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Andrey DO, Ferry T, Siegenthaler N, Fletcher C, Calmy A, Lina G, Emonet S. Unusual staphylococcal toxic shock syndrome presenting as a scarlet-like fever. New Microbes New Infect 2015; 8:10-3. [PMID: 26543563 PMCID: PMC4590715 DOI: 10.1016/j.nmni.2015.08.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2015] [Revised: 07/15/2015] [Accepted: 08/07/2015] [Indexed: 10/30/2022] Open
Abstract
Diagnosis of nonmenstrual staphylococcal toxic shock syndrome (TSS) is often challenging. A female medical colleague had a rare entity, a staphylococcal pharyngitis complicated by TSS. The diagnosis was confirmed by isolation of tst-positive Staphylococcus aureus in throat culture and by identification of a specific Vβ2 expansion pattern of her T lymphocytes. Recent improvements in microbiology can be of great help for the diagnosis of nonmenstrual TSS.
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Affiliation(s)
- D O Andrey
- Service of Infectious Diseases, Department of Medical Specialties, Switzerland
| | - T Ferry
- Hospices Civils de Lyon, CIRI, Université Lyon 1, Inserm U1111, CNRS UMR5308, Ecole Normale Supérieure de Lyon, Centre National de Référence des Staphylocoques, Lyon, France
| | - N Siegenthaler
- Intensive Care Unit, Department of Anaesthesiology, Pharmacology and Intensive Care, Switzerland
| | - C Fletcher
- St Helens Clinical Commissioning Group, United Kingdom
| | - A Calmy
- Service of Infectious Diseases, Department of Medical Specialties, Switzerland
| | - G Lina
- Hospices Civils de Lyon, CIRI, Université Lyon 1, Inserm U1111, CNRS UMR5308, Ecole Normale Supérieure de Lyon, Centre National de Référence des Staphylocoques, Lyon, France
| | - S Emonet
- Service of Infectious Diseases, Department of Medical Specialties, Switzerland ; Bacteriology Laboratory, Department of Laboratories and Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
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Clostridium perfringens epsilon toxin: a malevolent molecule for animals and man? Toxins (Basel) 2013; 5:2138-60. [PMID: 24284826 PMCID: PMC3847718 DOI: 10.3390/toxins5112138] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 10/30/2013] [Accepted: 10/31/2013] [Indexed: 12/27/2022] Open
Abstract
Clostridium perfringens is a prolific, toxin-producing anaerobe causing multiple diseases in humans and animals. One of these toxins is epsilon, a 33 kDa protein produced by Clostridium perfringens (types B and D) that induces fatal enteric disease of goats, sheep and cattle. Epsilon toxin (Etx) belongs to the aerolysin-like toxin family. It contains three distinct domains, is proteolytically-activated and forms oligomeric pores on cell surfaces via a lipid raft-associated protein(s). Vaccination controls Etx-induced disease in the field. However, therapeutic measures are currently lacking. This review initially introduces C. perfringens toxins, subsequently focusing upon the Etx and its biochemistry, disease characteristics in various animals that include laboratory models (in vitro and in vivo), and finally control mechanisms (vaccines and therapeutics).
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Krakauer T. Update on staphylococcal superantigen-induced signaling pathways and therapeutic interventions. Toxins (Basel) 2013; 5:1629-54. [PMID: 24064719 PMCID: PMC3798877 DOI: 10.3390/toxins5091629] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 09/13/2013] [Accepted: 09/13/2013] [Indexed: 12/20/2022] Open
Abstract
Staphylococcal enterotoxin B (SEB) and related bacterial toxins cause diseases in humans and laboratory animals ranging from food poisoning, acute lung injury to toxic shock. These superantigens bind directly to the major histocompatibility complex class II molecules on antigen-presenting cells and specific Vβ regions of T-cell receptors (TCR), resulting in rapid hyper-activation of the host immune system. In addition to TCR and co-stimulatory signals, proinflammatory mediators activate signaling pathways culminating in cell-stress response, activation of NFκB and mammalian target of rapamycin (mTOR). This article presents a concise review of superantigen-activated signaling pathways and focuses on the therapeutic challenges against bacterial superantigens.
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Affiliation(s)
- Teresa Krakauer
- Department of Immunology, Integrated Toxicology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, MD 21702 5011, USA.
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Abstract
OBJECTIVE Septic syndromes are the leading causes of mortality in intensive care units. In patients, the occurrence of sepsis-induced immune suppression is associated with delayed mortality, although the exact role of lymphocyte dysfunctions is not well established. The objective of this study was to investigate T-cell receptor diversity, an important feature of T-cell response, in patients with septic shock. DESIGN Preliminary prospective observational study. SETTING Adult intensive care units in a university hospital. SUBJECTS Patients with septic shock (n = 41) sampled twice after the onset of shock (early after inclusion [day 1] and at the end of the first week [day 7]). MEASUREMENTS AND MAIN RESULTS Using a novel molecular biology technique, the combinatorial diversity of human T-cell receptor β-chain (TRB locus) was measured in peripheral blood. Patients with septic shock presented with a marked decreased T-cell receptor diversity after the onset of shock in comparison with normal values. Importantly, in paired samples, a very steep recovery slope of T-cell receptor diversity, never described in other clinical situations, was observed between day 1 and day 7 (p < 0.0001, Wilcoxon's paired test). Decreased T-cell receptor diversity was associated with mortality (log-rank test, p = 0.0058; hazard ratio = 4.48; 95% confidence interval 1.96-53.32), and the development of nosocomial infections (p < 0.05, Mann-Whitney U test). CONCLUSION Our results show for the first time that septic patients present with a marked decreased T-cell receptor diversity that returned rapidly toward normal values over time. This opens novel cognitive research perspectives that deserve to be investigated in experimental models of sepsis. After confirmation in larger cohorts of these preliminary results, T-cell receptor diversity measurements may become a crucial tool to monitor immune functions in ICU patients.
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Krakauer T. PI3K/Akt/mTOR, a pathway less recognized for staphylococcal superantigen-induced toxicity. Toxins (Basel) 2012; 4:1343-66. [PMID: 23202320 PMCID: PMC3509712 DOI: 10.3390/toxins4111343] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 11/12/2012] [Accepted: 11/13/2012] [Indexed: 12/27/2022] Open
Abstract
Immunostimulating staphylococcal enterotoxin B (SEB) and related superantigenic toxins cause diseases in humans and laboratory animals by activating cells of the immune system. These toxins bind directly to the major histocompatibility complex (MHC) class II molecules on antigen-presenting cells and specific Vβ regions of T-cell receptors (TCR), resulting in hyperactivation of both T lymphocytes and monocytes/macrophages. Activated host cells produce excessive amounts of proinflammatory cytokines and chemokines, especially tumor necrosis factor α, interleukin 1 (IL-1), IL-2, interferon γ (IFNγ), and macrophage chemoattractant protein 1 causing clinical symptoms of fever, hypotension, and shock. The well-explored signal transduction pathways for SEB-induced toxicity downstream from TCR/MHC ligation and interaction of cell surface co-stimulatory molecules include the mitogen-activated protein kinase cascades and cytokine receptor signaling, culminating in NFκB activation. Independently, IL-2, IFNγ, and chemokines from activated T cells signal via the phosphoinositide 3-kinase (PI3K), the serine/threonine kinases, Akt and mammalian target of rapamycin (mTOR) pathways. This article reviews the signaling molecules induced by superantigens in the activation of PI3K/Akt/mTOR pathways leading to staphylococcal superantigen-induced toxicity and updates potential therapeutics against superantigens.
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Affiliation(s)
- Teresa Krakauer
- Department of Immunology, Integrated Toxicology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, MD 21702, USA.
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Dauwalder O, Venet F, Javouhey E, Badiou C, Gillet Y, Guignant C, Plainvert C, Etienne J, Poyart C, Vandenesch F, Lina G, Monneret G. Assessment of cellular immune parameters in paediatric toxic shock syndrome: a report of five cases. ACTA ACUST UNITED AC 2012; 66:116-9. [PMID: 22587469 DOI: 10.1111/j.1574-695x.2012.00990.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 05/08/2012] [Accepted: 05/08/2012] [Indexed: 01/08/2023]
Abstract
Toxic shock syndrome (TSS) and septic shock (SS) share many clinical signs of an exacerbated inflammatory response. In this report, we investigated whether TSS presents similar features of delayed immunosuppression as described in SS. Five children with TSS from paediatric intensive care units in a university hospital were monitored. TSS cases were defined by the association of standardized clinical signs of TSS and confirmed by measurement of specific Vbeta expansions corresponding to toxin gene profile of the isolated strains. As in SS, an increased percentage of circulating regulatory T cells (Treg) was observed in patients with TSS. However, in contrast to SS, neither lymphopenia nor decreased HLA-DR expression on monocytes was measured. In conclusion, whereas SS and TSS exhibited similar clinical presentation, the present observation suggests that respective pathophysiological mechanisms induce different immune alterations. Future studies must isolate and better characterize the phenotypic and functional properties of Treg subsets during TSS to understand the mechanisms sustaining their increase, especially the putative role of superantigens.
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Affiliation(s)
- Olivier Dauwalder
- Centre National de Références des Staphylocoques, Faculté de Médecine Lyon Est, Université de Lyon, France.
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Adrait A, Lebert D, Trauchessec M, Dupuis A, Louwagie M, Masselon C, Jaquinod M, Chevalier B, Vandenesch F, Garin J, Bruley C, Brun V. Development of a Protein Standard Absolute Quantification (PSAQ™) assay for the quantification of Staphylococcus aureus enterotoxin A in serum. J Proteomics 2012; 75:3041-9. [DOI: 10.1016/j.jprot.2011.11.031] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 11/23/2011] [Accepted: 11/26/2011] [Indexed: 10/14/2022]
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Chocs toxiques dans les infections à cocci à Gram positif. MEDECINE INTENSIVE REANIMATION 2012. [DOI: 10.1007/s13546-012-0460-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Xu SX, McCormick JK. Staphylococcal superantigens in colonization and disease. Front Cell Infect Microbiol 2012; 2:52. [PMID: 22919643 PMCID: PMC3417409 DOI: 10.3389/fcimb.2012.00052] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 03/29/2012] [Indexed: 12/28/2022] Open
Abstract
Superantigens (SAgs) are a family of potent immunostimulatory exotoxins known to be produced by only a few bacterial pathogens, including Staphylococcus aureus. More than 20 distinct SAgs have been characterized from different S. aureus strains and at least 80% of clinical strains harbor at least one SAg gene, although most strains encode many. SAgs have been classically associated with food poisoning and toxic shock syndrome (TSS), for which these toxins are the causative agent. TSS is a potentially fatal disease whereby SAg-mediated activation of T cells results in overproduction of cytokines and results in systemic inflammation and shock. Numerous studies have also shown a possible role for SAgs in other diseases such as Kawasaki disease (KD), atopic dermatitis (AD), and chronic rhinosinusitis (CRS). There is also now a rich understanding of the mechanisms of action of SAgs, as well as their structures and function. However, we have yet to discover what purpose SAgs play in the life cycle of S. aureus, and why such a wide array of these toxins exists. This review will focus on recent developments within the SAg field in terms of the molecular biology of these toxins and their role in both colonization and disease.
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Affiliation(s)
- Stacey X Xu
- Department of Microbiology and Immunology, Centre for Human Immunology, Schulich School of Medicine and Dentistry, University of Western Ontario, London ON, Canada
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Rasigade JP, Thomas D, Perpoint T, Peyramond D, Chidiac C, Etienne J, Vandenesch F, Lina G, Ferry T. T-cell response to superantigen restimulation during menstrual toxic shock syndrome. ACTA ACUST UNITED AC 2011; 62:368-71. [PMID: 21492259 DOI: 10.1111/j.1574-695x.2011.00808.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Menstrual toxic shock syndrome (MTSS) is a severe toxin-mediated disease associated with Staphylococcus aureus producing toxic shock syndrome toxin 1 (TSST-1), a superantigen that mediates a potent activation of Vβ-2 T cells. In animal models, superantigen treatment of responsive T cells induces their initial proliferation, followed by unresponsiveness upon further superantigen stimulation. To determine whether T cell unresponsiveness occurs in humans during the acute phase of MTSS, we collected T cells from a patient with MTSS and restimulated them ex vivo with recombinant TSST-1. The expansion of T cells collected during the acute phase of disease was compared with positive controls including basal-state T cells (collected 70 days after MTSS) restimulated with TSST-1, and T cells stimulated with enterotoxin B superantigen. We found that TSST-1-induced expansion of acute phase T cells was not inferior to that observed in positive controls. We conclude that T cells were still reactive to TSST-1 during the acute phase of MTSS in this patient. As the persistence of TSST-1 production could thus be associated with further expansion of TSST-1-reactive T cells and a rapid worsening of symptoms, this study adds further support to the need for immediate eradication of the focus of infection as soon as MTSS is suspected.
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Affiliation(s)
- Jean-Philippe Rasigade
- INSERM U851, National Reference Center for Staphylococci, University of Lyon Claude Bernard, Lyon, France.
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The systemic and pulmonary immune response to staphylococcal enterotoxins. Toxins (Basel) 2010; 2:1898-912. [PMID: 22069664 PMCID: PMC3153275 DOI: 10.3390/toxins2071898] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Accepted: 07/12/2010] [Indexed: 11/21/2022] Open
Abstract
In response to environmental cues the human pathogen Staphylococcus aureus synthesizes and releases proteinaceous enterotoxins. These enterotoxins are natural etiologic entities of severe food poisoning, toxic shock syndrome, and acute diseases. Staphylococcal enterotoxins are currently listed as Category B Bioterrorism Agents by the Center for Disease Control and Prevention. They are associated with respiratory illnesses, and may contribute to exacerbation of pulmonary disease. This likely stems from the ability of Staphylococcal enterotoxins to elicit powerful episodes of T cell stimulation resulting in release of pro-inflammatory cytokines. Here, we discuss the role of the immune system and potential mechanisms of disease initiation and progression.
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Linking innate and adaptive immunity: human Vgamma9Vdelta2 T cells enhance CD40 expression and HMGB-1 secretion. Mediators Inflamm 2009; 2009:819408. [PMID: 19841752 PMCID: PMC2762119 DOI: 10.1155/2009/819408] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2009] [Accepted: 07/17/2009] [Indexed: 11/30/2022] Open
Abstract
γδ T cells play an important role in regulating the immune response to stress stimuli; however, the mean by which these innate lymphocytes fulfill this function remains
poorly defined. The main subset of human peripheral blood γδ T cells responds to
nonpeptidic antigens, such as isopentylpyrophosphate (IPP), a metabolite in the
mevalonate pathway for both eukaryote and prokaryote cells. IPP-primed γδ T cells
significantly augment the inflammatory response mediated by monocytes and αβ T cells
to TSST-1, the staphylococcal superantigen that is the major causative agent of toxic
shock syndrome. Here we show that the small pool of activated peripheral γδ T cells
induces an early upregulation of CD40 on monocytes and the local release of High
Mobility Group Box-1 (HMGB-1), the molecule designated as the late mediator of
systemic inflammation. This finding provides a new basis for how γδ T cells may serve
as influential modulators of both endogenous and exogenous stress stimuli.
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Hayworth JL, Kasper KJ, Leon-Ponte M, Herfst CA, Yue D, Brintnell WC, Mazzuca DM, Heinrichs DE, Cairns E, Madrenas J, Hoskin DW, McCormick JK, Haeryfar SMM. Attenuation of massive cytokine response to the staphylococcal enterotoxin B superantigen by the innate immunomodulatory protein lactoferrin. Clin Exp Immunol 2009; 157:60-70. [PMID: 19659771 DOI: 10.1111/j.1365-2249.2009.03963.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Staphylococcal enterotoxin B (SEB) is a pyrogenic exotoxin and a potent superantigen which causes massive T cell activation and cytokine secretion, leading to profound immunosuppression and morbidity. The inhibition of SEB-induced responses is thus considered a goal in the management of certain types of staphylococcal infections. Lactoferrin (LF) is a multi-functional glycoprotein with both bacteriostatic and bactericidal activities. In addition, LF is known to have potent immunomodulatory properties. Given the anti-microbial and anti-inflammatory properties of this protein, we hypothesized that LF can modulate T cell responses to SEB. Here, we report that bovine LF (bLF) was indeed able to attenuate SEB-induced proliferation, interleukin-2 production and CD25 expression by human leucocyte antigen (HLA)-DR4 transgenic mouse T cells. This inhibition was not due to bLF's iron-binding capacity, and could be mimicked by the bLF-derived peptide lactoferricin. Cytokine secretion by an engineered SEB-responsive human Jurkat T cell line and by peripheral blood mononuclear cells from healthy donors was also inhibited by bLF. These findings reveal a previously unrecognized property of LF in modulation of SEB-triggered immune activation and suggest a therapeutic potential for this naturally occurring protein during toxic shock syndrome.
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Affiliation(s)
- J L Hayworth
- Department of Microbiology and Immunology, University of Western Ontario, ON, USA
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Diverse enterotoxin gene profiles among clonal complexes of Staphylococcus aureus isolates from the Bronx, New York. Appl Environ Microbiol 2009; 75:6839-49. [PMID: 19749060 DOI: 10.1128/aem.00272-09] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Staphylococcal enterotoxins (SE) can cause toxin-mediated disease, and those that function as superantigens are implicated in the pathogenesis of allergic diseases. The prevalence of 19 enterotoxin genes was determined by PCR in clinical S. aureus strains derived from wounds (108) and blood (99). We performed spa typing and multilocus sequence typing (MLST) to determine clonal origin, and for selected strains staphylococcal enterotoxin B (SEB) production was measured by enzyme-linked immunosorbent assay. Strains carried a median of five SE genes. For most SE genes, the prevalence rates among methicillin-resistant and methicillin-sensitive S. aureus isolates, as well as wound- and blood-derived isolates, did not differ. At least one SE gene was detected in all except two S. aureus isolates (>99%). Complete egc clusters were found in only 11% of S. aureus isolates, whereas the combination of sed, sej, and ser was detected in 24% of clinical strains. S. aureus strains exhibited distinct combinations of SE genes, even if their pulsed-field gel electrophoresis and MLST patterns demonstrated clonality. USA300 strains also showed considerable variability in SE content, although they contained a lower number of SE genes (mean, 3). By contrast, SE content was unchanged in five pairs of serial isolates. SEB production by individual strains varied up to 200-fold, and even up to 15-fold in a pair of serial isolates. In conclusion, our results illustrate the genetic diversity of S. aureus strains with respect to enterotoxin genes and suggest that horizontal transfer of mobile genetic elements encoding virulence genes occurs frequently.
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Abstract
Toxic shock syndrome (TSS) is an acute, multi-system, toxin-mediated illness, often resulting in multi-organ failure. It represents the most fulminant expression of a spectrum of diseases caused by toxin-producing strains of Staphylococcus aureus and Streptococcus pyogenes (group A streptococcus). The importance of Gram-positive organisms as pathogens is increasing, and TSS is likely to be underdiagnosed in patients with staphylococcal or group A streptococcal infection who present with shock. TSS results from the ability of bacterial toxins to act as superantigens, stimulating immune-cell expansion and rampant cytokine expression in a manner that bypasses normal MHC-restricted antigen processing. A repetitive cycle of cell stimulation and cytokine release results in a cytokine avalanche that causes tissue damage, disseminated intravascular coagulation, and organ dysfunction. Specific therapy focuses on early identification of the illness, source control, and administration on antimicrobial agents including drugs capable of suppressing toxin production (eg, clindamycin, linezolid). Intravenous immunoglobulin has the potential to neutralise superantigen and to mitigate subsequent tissue damage.
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Loughman JA, Fritz SA, Storch GA, Hunstad DA. Virulence gene expression in human community-acquired Staphylococcus aureus infection. J Infect Dis 2009; 199:294-301. [PMID: 19115951 DOI: 10.1086/595982] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Isolates of methicillin-resistant Staphylococcus aureus (MRSA) were once linked uniformly with hospital-associated infections; however, community-acquired MRSA (CA-MRSA) now represents an emerging threat worldwide. To examine the association of differential virulence gene expression with outcomes of human infection, we measured transcript levels of target staphylococcal genes directly in clinical samples from children with active known or suspected CA-MRSA infections. Virulence genes encoding secreted toxins, including Panton-Valentine leukocidin, were highly expressed during superficial and invasive CA-MRSA infections. In contrast, increased expression of surface-associated protein A was linked only with invasive disease. Comparisons with laboratory-grown corresponding clinical isolates revealed that tissue-specific expression profiles reflect the activity of the staphylococcal accessory gene regulator during human infection. These results represent the first demonstration of staphylococcal gene expression and regulation directly in human tissue. Such analysis will help to unravel the complex interactions between CA-MRSA and its host environmental niches during disease development.
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Affiliation(s)
- Jennifer A Loughman
- Department of Pediatrics, Washington University School of Medicine, Saint Louis, Missouri 63110-1093, USA
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Staphylococcus aureus superantigens elicit redundant and extensive human Vbeta patterns. Infect Immun 2009; 77:2043-50. [PMID: 19255190 DOI: 10.1128/iai.01388-08] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Staphylococcus aureus can produce a wide variety of exotoxins, including toxic shock syndrome toxin 1 (TSST-1), staphylococcal enterotoxins, and staphylococcal enterotoxin-like toxins. These toxins share superantigenic activity. To investigate the beta chain (Vbeta) specificities of each of these toxins, TSST-1 and all known S. aureus enterotoxins and enterotoxin-like toxins were produced as recombinant proteins and tested for their ability to induce the selective in vitro expansion of human T cells bearing particular Vbeta T-cell receptors (TCR). Although redundancies were observed between the toxins and the Vbeta populations, each toxin induced the expansion of distinct Vbeta subsets, including enterotoxin H and enterotoxin-like toxin J. Surprisingly, the Vbeta signatures were not associated with a specific phylogenic group of toxins. Interestingly, each human Vbeta analyzed in this study was stimulated by at least one staphylococcal superantigen, suggesting that the bacterium derives a selective advantage from targeting the entire human TCR Vbeta panel.
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