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https://www.readbyqxmd.com/read/29328525/a-role-of-sialic-acid-containing-glycans-of-matrix-metalloproteinase-9-mmp-9-in-the-interaction-between-mmp-9-and-staphylococcal-superantigen-like-protein-5-ssl5
#1
Chisato Kurisaka, Teruaki Oku, Saotomo Itoh, Tsutomu Tsuji
The staphylococcal superantigen-like proteins (SSLs) exhibit no superantigenic activity but have recently been considered to act as immune suppressors. It was previously reported that SSL5 bound to P-selectin glycoprotein ligand-1 (PSGL-1) and matrix metalloproteinase (MMP)-9, leading to inhibition of leukocyte adhesion and invasion. These interactions were suggested to depend on sialic acid-containing glycans of MMP-9, but the roles of sialic acids in the interaction between SSL5 and MMP-9 are still controversial...
January 12, 2018: Microbiology and Immunology
https://www.readbyqxmd.com/read/29247497/the-prevalence-of-antibody-responses-against-staphylococcus-aureus-antigens-in-patients-with-atopic-dermatitis-a-systematic-review-and-meta-analysis
#2
REVIEW
J de Wit, J E E Totté, F J M van Buchem, S G M A Pasmans
Staphylococcus (S.) aureus plays a role in the pathogenesis of atopic dermatitis (AD), possibly via the expression of various virulence antigens. An altered antibody response towards these antigens might contribute to inflammation. We aimed to provide an overview of the varying prevalences and odds of antibody responses against S. aureus antigens in AD patients. Data were systematically obtained from Embase, Medline, Web of Science, Scopus, Cochrane, PubMed and Google Scholar (up to February 12th 2016). We selected all original observational and experimental studies assessing anti-staphylococcal antibodies in serum of AD patients...
December 16, 2017: British Journal of Dermatology
https://www.readbyqxmd.com/read/29237775/induction-of-immunosuppressive-cd8-cd25-foxp3-regulatory-t-cells-by-suboptimal-stimulation-with-staphylococcal-enterotoxin-c1
#3
Juyeun Lee, Nogi Park, Joo Youn Park, Barbara L F Kaplan, Stephen B Pruett, Juw Won Park, Yong Ho Park, Keun Seok Seo
Superantigens (SAgs) produced by Staphylococcus aureus at high concentrations induce proliferation of T cells bearing specific TCR Vβ sequences and massive cytokinemia that cause toxic shock syndrome. However, the biological relevance of SAgs produced at very low concentrations during asymptomatic colonization or chronic infections is not understood. In this study, we demonstrate that suboptimal stimulation of human PBMCs with a low concentration (1 ng/ml) of staphylococcal enterotoxin C1, at which half-maximal T cell proliferation was observed, induced CD8+CD25+ T cells expressing markers related to regulatory T cells (Tregs), such as IFN-γ, IL-10, TGF-β, FOXP3, CD28, CTLA4, TNFR2, CD45RO, and HLA-DR...
December 13, 2017: Journal of Immunology: Official Journal of the American Association of Immunologists
https://www.readbyqxmd.com/read/29233782/expression-of-superantigens-and-the-agr-system-in-staphylococcus-epidermidis
#4
Valéria Cataneli Pereira, Luiza Pinheiro, Adilson Oliveira, Katheryne Martins, Danilo Riboli, Maria de Lourdes Cunha
Infections with coagulase-negative staphylococci (CoNS) can involve the production of toxins such as superantigens, which contribute to tissue degradation and inflammatory immune responses. The accessory gene regulator (agr) quorum sensing system coordinates the expression of most S. aureus virulence factors. Therefore, the aim of this study was to investigate the expression of these superantigens and the presence of the agr locus in CoNS strains isolated from blood cultures. PCR was used to detect enterotoxin and agr genes and expression was analyzed by RT-PCR...
December 9, 2017: Microbial Pathogenesis
https://www.readbyqxmd.com/read/29233606/staphylococcus-aureus-and-atopic-dermatitis-a-complex-and-evolving-relationship
#5
REVIEW
Joan A Geoghegan, Alan D Irvine, Timothy J Foster
Staphylococcus aureus is frequently isolated from the skin of atopic dermatitis (AD) patients during flares. The normal microbiota is disrupted and the diversity of the microorganisms on the skin is reduced. Many species that produce inhibitors of S. aureus growth decline. Strains from S. aureus clonal complex 1 are enriched among AD sufferers whereas the CC30 strains most frequently isolated from nasal carriers in the normal population are much rarer in AD. S. aureus expresses several molecules that contribute to the intensity of symptoms, including δ-toxin which stimulates mast cells, α-toxin which damages keratinocytes, phenol-soluble modulins which stimulate cytokine release by keratinocytes, protein A which triggers inflammatory responses from keratinocytes, superantigens which trigger B cell expansion and cytokine release, and proinflammatory lipoproteins...
December 9, 2017: Trends in Microbiology
https://www.readbyqxmd.com/read/29229737/the-superantigen-toxic-shock-syndrome-toxin-1-alters-human-aortic-endothelial-cell-function
#6
Katarina Kulhankova, Kyle J Kinney, Jessica M Stach, Françoise A Gourronc, Isabella M Grumbach, Aloysius J Klingelhutz, Wilmara Salgado-Pabón
Staphylococcus aureus infective endocarditis (IE) is a fast-progressing and tissue destructive infection of the cardiac endothelium. The superantigens (SAgs) toxic shock syndrome toxin-1 (TSST-1), staphylococcal enterotoxin C (SEC), and the enterotoxin gene cluster (egc) play a novel and essential role in the etiology of S. aureus IE. Recent studies indicate that SAgs act at the infection site to cause tissue pathology and promote vegetation growth. The underlying mechanism of SAg involvement has not been clearly defined...
December 11, 2017: Infection and Immunity
https://www.readbyqxmd.com/read/29193036/cxcl4-is-a-novel-inducer-of-human-th17-cells-and-correlates-with-il-17-and-il-22-in-psoriatic-arthritis
#7
Alsya J Affandi, Sandra C Silva-Cardoso, Samuel Garcia, Emmerik F A Leijten, Tessa S van Kempen, Wioleta Marut, Joel A G van Roon, Timothy R D J Radstake
CXCL4 regulates multiple facets of the immune response and is highly upregulated in various Th17-associated rheumatic diseases. However, whether CXCL4 plays a direct role in the induction of IL-17 production by human CD4 T cells is currently unclear. Here, we demonstrated that CXCL4 induced human CD4 T cells to secrete IL-17 that co-expressed IFNγ and IL-22, and differentiated naïve CD4 T cells to become Th17-cytokine producing cells. In a co-culture system of human CD4 T cells with monocytes or myeloid dendritic cells, CXCL4 induced IL-17 production upon triggering by superantigen...
November 29, 2017: European Journal of Immunology
https://www.readbyqxmd.com/read/29174495/global-spread-of-mouse-adapted-staphylococcus-aureus-lineages-cc1-cc15-and-cc88-among-mouse-breeding-facilities
#8
Daniel M Mrochen, Dorothee Grumann, Daniel Schulz, Janine Gumz, Patricia Trübe, Kathleen Pritchett-Corning, Sarah Johnson, Werner Nicklas, Petra Kirsch, Karine Martelet, Jens van den Brandt, Sabine Berg, Barbara M Bröker, Siouxsie Wiles, Silva Holtfreter
We previously reported that laboratory mice from all global vendors are frequently colonized with Staphylococcus aureus (S. aureus). Genotyping of a snap sample of murine S. aureus isolates from Charles River, US, showed that mice were predominantly colonized with methicillin-sensitive CC88 strains. Here, we expanded our view and investigated whether laboratory mice from other global animal facilities are colonized with similar strains or novel S. aureus lineages, and whether the murine S. aureus isolates show features of host adaptation...
November 20, 2017: International Journal of Medical Microbiology: IJMM
https://www.readbyqxmd.com/read/29149330/s101-an-inhibitor-of-proliferating-t-cells-rescues-mice-from-superantigen-induced-shock
#9
Alexei Shir, Shoshana Klein, Idit Sagiv-Barfi, Tamar Geiger, Maya Zigler, Yael Langut, Nufar Edinger, Alexander Levitzki
Superantigens (SAg) are extremely potent bacterial toxins, which evoke a virulent immune response, inducing non-specific T-cell proliferation, rapid cytokine release and lethal toxic shock, for which there is no effective treatment. We previously developed a small molecule, S101, which potently inhibits proliferating T-cells (Sagiv-Barfi et al, Bioorg Med Chem (2010) 18:6404-6413). In a severe mouse model of toxic shock, a single injection of S101 given together with superantigen challenge, rescued 100% of the mice...
November 15, 2017: Journal of Infectious Diseases
https://www.readbyqxmd.com/read/29100762/staphylococcal-pathogenicity-islands-movers-and-shakers-in-the-genomic-firmament
#10
REVIEW
Richard P Novick, Geeta Ram
The staphylococcal pathogenicity islands (SaPIs) are highly mobile 15kb genomic islands that carry superantigen genes and other virulence factors and are mobilized by helper phages. Helper phages counteract the SaPI repressor to induce the SaPI replication cycle, resulting in encapsidation in phage like particles, enabling high frequency transfer. The SaPIs split from a protophage lineage in the distant past, have evolved a variety of novel and salient features, and have become an invaluable component of the staphylococcal genome...
August 2017: Current Opinion in Microbiology
https://www.readbyqxmd.com/read/29099691/phylogenetic-distribution-and-expression-of-a-penicillin-binding-protein-homologue-ear-and-its-significance-in-virulence-of-staphylococcus-aureus
#11
Vineet K Singh, Robert P Ring, Vijay Aswani, Mary E Stemper, Jennifer Kislow, Zhan Ye, Sanjay K Shukla
PURPOSE: Staphylococcus aureus is an opportunistic human pathogen that can cause serious infections in humans. A plethora of known and putative virulence factors are produced by staphylococci that collectively orchestrate pathogenesis. Ear protein (Escherichia coli ampicillin resistance) in S. aureus is an exoprotein in COL strain, predicted to be a superantigen, and speculated to play roles in antibiotic resistance and virulence. The goal of this study was to determine if expression of ear is modulated by single nucleotide polymorphisms in its promoter and coding sequences and whether this gene plays roles in antibiotic resistance and virulence...
November 3, 2017: Journal of Medical Microbiology
https://www.readbyqxmd.com/read/29095152/structure-of-the-staphylococcal-enterotoxin-b-vaccine-candidate-s19-showing-eliminated-superantigen-activity
#12
Woo Hyeon Jeong, Dong Hyun Song, Gyeung Haeng Hur, Seong Tae Jeong
Four mutations (N23A, Y90A, R110A and F177A) were introduced into S19, a vaccine candidate for staphylococcal enterotoxin B (SEB), resulting in a lower binding affinity towards the T-cell receptor beta chain (TCB) and reducing its superantigen activity. The structure of S19 was solved and was superposed on the native or complex structure of SEB. In the superposition model, mutations that were introduced seemed to reduce the number of hydrogen bonds at the SEB-TCB interface. S19 also displayed an unexpected structural change around the flexible-loop region owing to the Y90A mutation...
November 1, 2017: Acta Crystallographica. Section F, Structural Biology Communications
https://www.readbyqxmd.com/read/29056305/exotoxins-and-endotoxins-inducers-of-inflammatory-cytokines
#13
REVIEW
Jean-Marc Cavaillon
Endotoxins and exotoxins are among the most potent bacterial inducers of cytokines. During infectious processes, the production of inflammatory cytokines including tumor necrosis factor (TNF), interleukin-1β (IL-1β), gamma interferon (IFNγ) and chemokines orchestrates the anti-infectious innate immune response. However, an overzealous production, leading up to a cytokine storm, can be deleterious and contributes to mortality consecutive to sepsis or toxic shock syndrome. Endotoxins of Gram-negative bacteria (lipopolysaccharide, LPS) are particularly inflammatory because they generate auto-amplificatory loops after activation of monocytes/macrophages...
October 19, 2017: Toxicon: Official Journal of the International Society on Toxinology
https://www.readbyqxmd.com/read/29051689/detection-of-newly-defined-superantigenic-toxin-genes-and-coagulase-gene-polymorphism-in-staphylococcus-aureus-isolates
#14
Bareq A Al-Ajealy, Maysa S M Al-Shukri, Hassan S Al-Jumaily
The current study aims to use coagulase (coa) polymorphism gene to identify Staphylococcus aureus isolated from stool samples, evaluate the efficiency of these methods in discriminating variable strains, and compare these subtypes with antibiotypes. A total of 100 specimens were collected from patients in Babylon province, Iraq, between July 2016 and September 2016. Twenty S. aureus strains were isolated and identified using standard laboratory microbiological tests. The bacterial isolates were then examined by coa gene restriction fragment length polymorphism genotyping...
October 2017: Reviews in Medical Microbiology: a Journal of the Pathological Society of Great Britain and Ireland
https://www.readbyqxmd.com/read/28990820/interleukin-2-secretion-by-t-cells-for-detection-of-biologically-active-staphylococcal-enterotoxin-type-e
#15
Reuven Rasooly, Paula Do, Bradley J Hernlem
Staphylococcus aureus is a significant worldwide source of clinical infections and foodborne illnesses; it acts through the synthesis of a group of enterotoxins (SEs) that cause gastroenteritis and also function as superantigens that activate T cells, resulting in massive cytokine production, yielding life-threatening toxicity. It is important that methods for detection and quantification of these toxins respond to their activity and not just the presence of the toxin molecule, which may be deactivated. Traditionally, live animals have been used to test for emesis following administration of the toxin-containing sample...
October 9, 2017: Journal of Food Protection
https://www.readbyqxmd.com/read/28967544/wild-rodents-and-shrews-are-natural-hosts-of-staphylococcus-aureus
#16
Daniel M Mrochen, Daniel Schulz, Stefan Fischer, Kathrin Jeske, Heba El Gohary, Daniela Reil, Christian Imholt, Patricia Trübe, Josef Suchomel, Emilie Tricaud, Jens Jacob, Marta Heroldová, Barbara M Bröker, Birgit Strommenger, Birgit Walther, Rainer G Ulrich, Silva Holtfreter
Laboratory mice are the most commonly used animal model for Staphylococcus aureus infection studies. We have previously shown that laboratory mice from global vendors are frequently colonized with S. aureus. Laboratory mice originate from wild house mice. Hence, we investigated whether wild rodents, including house mice, as well as shrews are naturally colonized with S. aureus and whether S. aureus adapts to the wild animal host. 295 animals of ten different species were caught in different locations over four years (2012-2015) in Germany, France and the Czech Republic...
September 22, 2017: International Journal of Medical Microbiology: IJMM
https://www.readbyqxmd.com/read/28943993/effectiveness-of-a-glycylcycline-antibiotic-for-reducing-the-pathogenicity-of-superantigen-producing-methicillin-resistant-staphylococcus-aureus-in-burn-wounds
#17
Lauren B Nosanov, Daniel Y Jo, Pranay R Randad, Lauren T Moffatt, Bonnie C Carney, Rachel T Ortiz, Jeffrey W Shupp
Objective: Burn-injured patients are highly susceptible to infectious complications, which are often associated with increased morbidity and mortality. Rates of antibiotic resistance have increased, and resistant species such as methicillin-resistant Staphylococcus aureus provide additional challenges in the form of virulence factors. Proteins can disrupt local healing, leading to systemic immune disruption. To optimize outcomes, treatments that reduce pathogenicity must be identified. This study aims to compare a glycylcycline antibiotic-tigecycline-with clindamycin for effectiveness in treating superantigenic methicillin-resistant Staphylococcus aureus in burn wounds...
2017: Eplasty
https://www.readbyqxmd.com/read/28939882/genetic-loci-of-staphylococcus-aureus-associated-with-anti-neutrophil-cytoplasmic-autoantibody-anca-associated-vasculitides
#18
Corinna Glasner, Marcus C de Goffau, Mirjan M van Timmeren, Mirja L Schulze, Benita Jansen, Mehri Tavakol, Willem J B van Wamel, Coen A Stegeman, Cees G M Kallenberg, Jan P Arends, John W Rossen, Peter Heeringa, Jan Maarten van Dijl
The proteinase 3 (PR3)-positive anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) granulomatosis with polyangiitis (GPA) has been associated with chronic nasal S. aureus carriage, which is a risk factor for disease relapse. The present study was aimed at comparing the genetic make-up of S. aureus isolates from PR3-ANCA-positive GPA patients with that of isolates from patients suffering from myeloperoxidase (MPO)-ANCA-positive AAV, and isolates from healthy controls. Based on a DNA microarray-based approach, we show that not only PR3-ANCA-positive GPA patients, but also MPO-ANCA-positive AAV patients mainly carried S...
September 22, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28934904/clonal-deletion-of-t-cell-repertoires-with-specific-t-cell-receptor-v%C3%AE-chains-by-two-endogenous-superantigens-in-nc-nga-mice
#19
Kozo Ohkusu-Tsukada, Teruyo Tsukada, Kimimasa Takahashi
Superantigens (SAgs) are powerful T-cell stimulatory proteins. Because an atopic dermatitis (AD) model NC/Nga mice had two endogenous SAgs, namely minor lymphocyte-stimulating locus-1(a) (Mls-1(a)) and mouse mammary tumor virus (MMTV)(SHN), SAg-responsive T-cells bearing Vβ5.1, Vβ6, Vβ8.1, Vβ8.2, Vβ8.3, Vβ9, and Vβ11 should be endogenously deleted. Here, we discuss that the endogenous SAgs-expression may be involved in AD-sensitivity in NC/Nga mice.
November 2017: Bioscience, Biotechnology, and Biochemistry
https://www.readbyqxmd.com/read/28901485/a-novel-non%C3%A2-contact-communication-between-human-keratinocytes-and-t-cells-exosomes-derived-from-keratinocytes-support-superantigen%C3%A2-induced-proliferation-of-resting-t-cells
#20
Xiao-Wei Cai, Rong Zhu, Lei Ran, Yi-Qian Li, Ke Huang, Jing Peng, Wei He, Chun-Li Zhou, Ru-Peng Wang
It is widely accepted that keratinocytes act as non‑professional antigen‑presenting cells and support superantigen‑induced proliferation of resting T cells; however, it remains unknown whether keratinocytes function in situ with T cells via a non‑contact mechanism. The current study used a transwell co‑culture system and demonstrated, for the first time to the best of the authors' knowledge, that HaCaT cells (the human keratinocyte cell line) did induce T cell proliferation via indirect contact. The data further indicated that exosomes, small membrane vesicles that transfer antigens to recipient cells, are also involved in the superantigen‑associated immunity of keratinocytes...
November 2017: Molecular Medicine Reports
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