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Gao SX, Sun C, Zhu YT, Zhao JB, Sun J, Zhou P, Jiang HY, Fan YA, Wei L, Zhang T, Guan JC. Exposure of pregnant rats to staphylococcal enterotoxin B increases offspring splenic Treg number and function via decreasing FoxP3 methylation. Immunobiology 2021; 226:152060. [PMID: 33529803 DOI: 10.1016/j.imbio.2021.152060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 01/12/2021] [Accepted: 01/20/2021] [Indexed: 12/30/2022]
Abstract
Staphylococcus aureus is an infectious pathogen that is relatively common, but that can cause severe disease in pregnant women and their fetus. We previously demonstrated that exposing pregnant rats to staphylococcal enterotoxin B (SEB) altered splenic CD4/CD8 T cell frequencies in their offspring. Whether prenatal SEB exposure impacts Tregs in these offspring, however, remains to be determined. As such, in this study, we intravenously injected pregnant rats with 15 μg of SEB on gestational day 16. Splenic tissue was then harvested from 1-, 3-, and 5-day-old neonatal rats and analyzed via flow cytometry to assess Treg numbers. In addition, FoxP3 expression levels were assessed via qPCR and western blotting, while FoxP3 methylation status was evaluated via methyl-DNA immunoprecipitation qPCR. Immunosuppression assays were additionally used to gauge Treg suppressive functionality. We found that exposing pregnant rats to SEB resulted in a significant increase in Treg numbers, FoxP3 expression, and Treg suppressive capacity in the spleens of both neonatal and adult offspring. In addition, total T cell, CD4+T cell, and non-Treg CD4+ T cell numbers were elevated in the spleens of offspring following prenatal SEB exposure. We additionally determined that SEB exposure resulted in a significant reduction in FoxP3 DNA methylation. Together, our results indicate that prenatal SEB exposure can markedly enhance offspring splenic Treg numbers and functionality at least in part by decreasing FoxP3 methylation.
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Affiliation(s)
- Shu-Xian Gao
- Anhui Key Laboratory of Infection and Immunity, Bengbu Medical College, Bengbu, Anhui 233030, PR China
| | - Chao Sun
- Anhui Key Laboratory of Infection and Immunity, Bengbu Medical College, Bengbu, Anhui 233030, PR China
| | - Yu-Ting Zhu
- Anhui Key Laboratory of Infection and Immunity, Bengbu Medical College, Bengbu, Anhui 233030, PR China
| | - Jia-Bao Zhao
- Anhui Key Laboratory of Infection and Immunity, Bengbu Medical College, Bengbu, Anhui 233030, PR China
| | - Jing Sun
- Anhui Key Laboratory of Infection and Immunity, Bengbu Medical College, Bengbu, Anhui 233030, PR China
| | - Ping Zhou
- Anhui Key Laboratory of Infection and Immunity, Bengbu Medical College, Bengbu, Anhui 233030, PR China
| | - Hao-Yuan Jiang
- An Under Graduate Student Majored Clinical Medicine, Bengbu Medical College, Anhui 233030, PR China
| | - Ying-Ao Fan
- An Under Graduate Student Majored Clinical Medicine, Bengbu Medical College, Anhui 233030, PR China
| | - Li Wei
- Anhui Key Laboratory of Infection and Immunity, Bengbu Medical College, Bengbu, Anhui 233030, PR China
| | - Tao Zhang
- Anhui Key Laboratory of Infection and Immunity, Bengbu Medical College, Bengbu, Anhui 233030, PR China
| | - Jun-Chang Guan
- Anhui Key Laboratory of Infection and Immunity, Bengbu Medical College, Bengbu, Anhui 233030, PR China; Department of Microbiology, Bengbu Medical College, Bengbu, Anhui 233030, PR China.
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2
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Kale SD, Mehrkens BN, Stegman MM, Kastelberg B, Carnes H, McNeill RJ, Rizzo A, Karyala SV, Coutermarsh-Ott S, Fretz JA, Sun Y, Koff JL, Rajagopalan G. "Small" Intestinal Immunopathology Plays a "Big" Role in Lethal Cytokine Release Syndrome, and Its Modulation by Interferon-γ, IL-17A, and a Janus Kinase Inhibitor. Front Immunol 2020; 11:1311. [PMID: 32676080 PMCID: PMC7333770 DOI: 10.3389/fimmu.2020.01311] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 05/22/2020] [Indexed: 12/11/2022] Open
Abstract
Chimeric antigen receptor T cell (CART) therapy, administration of certain T cell-agonistic antibodies, immune check point inhibitors, coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome–coronavirus 2 (SARS-CoV-2) and Toxic shock syndrome (TSS) caused by streptococcal as well as staphylococcal superantigens share one common complication, that is T cell-driven cytokine release syndrome (CRS) accompanied by multiple organ dysfunction (MOD). It is not understood whether the failure of a particular organ contributes more significantly to the severity of CRS. Also not known is whether a specific cytokine or signaling pathway plays a more pathogenic role in precipitating MOD compared to others. As a result, there is no specific treatment available to date for CRS, and it is managed only symptomatically to support the deteriorating organ functions and maintain the blood pressure. Therefore, we used the superantigen-induced CRS model in HLA-DR3 transgenic mice, that closely mimics human CRS, to delineate the immunopathogenesis of CRS as well as to validate a novel treatment for CRS. Using this model, we demonstrate that (i) CRS is characterized by a rapid rise in systemic levels of several Th1/Th2/Th17/Th22 type cytokines within a few hours, followed by a quick decline. (ii) Even though multiple organs are affected, small intestinal immunopathology is the major contributor to mortality in CRS. (iii) IFN-γ deficiency significantly protected from lethal CRS by attenuating small bowel pathology, whereas IL-17A deficiency significantly increased mortality by augmenting small bowel pathology. (iv) RNA sequencing of small intestinal tissues indicated that IFN-γ-STAT1-driven inflammatory pathways combined with enhanced expression of pro-apoptotic molecules as well as extracellular matrix degradation contributed to small bowel pathology in CRS. These pathways were further enhanced by IL-17A deficiency and significantly down-regulated in mice lacking IFN-γ. (v) Ruxolitinib, a selective JAK-1/2 inhibitor, attenuated SAg-induced T cell activation, cytokine production, and small bowel pathology, thereby completely protecting from lethal CRS in both WT and IL-17A deficient HLA-DR3 mice. Overall, IFN-γ-JAK-STAT-driven pathways contribute to lethal small intestinal immunopathology in T cell-driven CRS.
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Affiliation(s)
- Shiv D Kale
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
| | - Brittney N Mehrkens
- The Discipline of Microbiology and Immunology, Edward via College of Osteopathic Medicine, Blacksburg, VA, United States
| | - Molly M Stegman
- College of Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Bridget Kastelberg
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
| | - Henry Carnes
- The Discipline of Microbiology and Immunology, Edward via College of Osteopathic Medicine, Blacksburg, VA, United States
| | - Rachel J McNeill
- Research and Graduate Studies, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, United States
| | - Amy Rizzo
- Office of the University Veterinarian, Virginia Tech, Blacksburg, VA, United States
| | - Saikumar V Karyala
- Genomics Sequencing Center, Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
| | - Sheryl Coutermarsh-Ott
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, United States
| | - Jackie A Fretz
- Histology and Histomorphometry Laboratory, Department of Orthopedics and Rehabilitation, Yale School of Medicine, New Haven, CT, United States
| | - Ying Sun
- Division of Pulmonary Critical Care and Sleep Medicine, Department of Medicine, Yale School of Medicine, New Haven, CT, United States
| | - Jonathan L Koff
- Division of Pulmonary Critical Care and Sleep Medicine, Department of Medicine, Yale School of Medicine, New Haven, CT, United States
| | - Govindarajan Rajagopalan
- The Discipline of Microbiology and Immunology, Edward via College of Osteopathic Medicine, Blacksburg, VA, United States.,Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, United States.,Division of Pulmonary Critical Care and Sleep Medicine, Department of Medicine, Yale School of Medicine, New Haven, CT, United States
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van Gessel YA, Mani S, Bi S, Hammamieh R, Shupp JW, Das R, Coleman GD, Jett M. Functional Piglet Model for the Clinical Syndrome and Postmortem Findings Induced by Staphylococcal Enterotoxin B. Exp Biol Med (Maywood) 2016; 229:1061-71. [PMID: 15522843 DOI: 10.1177/153537020422901011] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Staphylococcal enterotoxin (SE) B causes serious gastrointestinal illness, and intoxication with this exotoxin can lead to lethal toxic shock syndrome. In order to overcome significant shortcomings of current rodent and nonhuman primate models, we developed a piglet model of lethal SEB intoxication. Fourteen-day-old Yorkshire piglets were given intravenous SEB, observed clinically, and sacrificed at 4, 6, 24, 48, 72, or 96 hrs posttreatment. Clinical signs were biphasic with pyrexia, vomiting, and diarrhea within 4 hrs, followed by terminal hypotension and shock by 96 hrs. Mild lymphoid lesions were identified as early as 24 hrs, with severe lymphadenopathy, splenomegaly, and prominent Peyer's patches found by 72 hrs. Widespread edema—most prominent in the mesentery, between loops of spiral colon, and in retroperitoneal connective tissue—was found in animals at 72 hrs. Additional histologic changes included perivascular aggregates of large lymphocytes variably present in the lung and brain, circulating lymphoblasts, and lymphocytic portal hepatitis. Preliminary molecular investigation using gene array has uncovered several gene profile changes that may have implications in the pathophysiology leading to irreversible shock. Five genes were selected for further study, and all showed increased mRNA levels subsequent to SEB exposure. The use of this piglet model will continue to elucidate the pathogenesis of SEB intoxication and facilitate the testing of new therapeutic regimens that may better correlate with human lesions.
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Affiliation(s)
- Yvonne A van Gessel
- Division of Pathology, Department of Molecular Pathology, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
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Krakauer T, Pradhan K, Stiles BG. Staphylococcal Superantigens Spark Host-Mediated Danger Signals. Front Immunol 2016; 7:23. [PMID: 26870039 PMCID: PMC4735405 DOI: 10.3389/fimmu.2016.00023] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 01/18/2016] [Indexed: 12/19/2022] Open
Abstract
Staphylococcal enterotoxin B (SEB) of Staphylococcus aureus, and related superantigenic toxins produced by myriad microbes, are potent stimulators of the immune system causing a variety of human diseases from transient food poisoning to lethal toxic shock. These protein toxins bind directly to specific Vβ regions of T-cell receptors (TCR) and major histocompatibility complex (MHC) class II on antigen-presenting cells, resulting in hyperactivation of 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. Because of superantigen-induced T cells skewed toward TH1 helper cells, and the induction of proinflammatory cytokines, superantigens can exacerbate autoimmune diseases. Upon TCR/MHC ligation, pathways induced by superantigens include the mitogen-activated protein kinase cascades and cytokine receptor signaling, resulting in activation of NFκB and the phosphoinositide 3-kinase/mammalian target of rapamycin pathways. Various mouse models exist to study SEB-induced shock including those with potentiating agents, transgenic mice and an “SEB-only” model. However, therapeutics to treat toxic shock remain elusive as host response genes central to pathogenesis of superantigens have only been identified recently. Gene profiling of a murine model for SEB-induced shock reveals novel molecules upregulated in multiple organs not previously associated with SEB-induced responses. The pivotal genes include intracellular DNA/RNA sensors, apoptosis/DNA damage-related molecules, immunoproteasome components, as well as antiviral and IFN-stimulated genes. The host-wide induction of these, and other, antimicrobial defense genes provide evidence that SEB elicits danger signals resulting in multi-organ damage and toxic shock. Ultimately, these discoveries might lead to novel therapeutics for various superantigen-based diseases.
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Affiliation(s)
- Teresa Krakauer
- Department of Immunology, Molecular Translational Sciences Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick , Frederick, MD , USA
| | - Kisha Pradhan
- Biology Department, Wilson College , Chambersburg, PA , USA
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5
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Gardner PJ, Yazid S, Chu CJ, Copland DA, Adamson P, Dick AD, Calder VL. TNFα Regulates SIRT1 Cleavage during Ocular Autoimmune Disease. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:1324-33. [DOI: 10.1016/j.ajpath.2015.01.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 12/23/2014] [Accepted: 01/07/2015] [Indexed: 11/30/2022]
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6
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Tirpude RJ, Batra H. Characteristics of Staphylococcus aureus isolated from acute, sub-acute and sub-clinical staphylococcosis in rabbits. WORLD RABBIT SCIENCE 2012. [DOI: 10.4995/wrs.2012.1203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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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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Shylaja R, Thakasi DKK, Murali HS, Reddy KPN, Batra HV. Application of a Chimeric Protein Construct having Enterotoxin B and Toxic Shock Syndrome Toxin Domains of S. aureus in Immunodiagnostics. Indian J Microbiol 2012; 52:449-55. [PMID: 23997338 DOI: 10.1007/s12088-012-0269-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Accepted: 03/17/2012] [Indexed: 11/30/2022] Open
Abstract
Staphylococcal enterotoxin B (SEB) and toxic shock syndrome toxin-1 are the super antigens responsible for diseases such as staphylococcal food poisoning and toxic shock syndrome. At low serum concentrations, SEB can trigger toxic shock, profound hypotension and multi organ failure and hence is recognized as biowarfare molecule. In this study, a multidomain fusion protein (r-TE) was generated with specificity for SEB and toxic shock syndrome toxin (Tsst-1). The fusion gene comprising the conserved regions of seb and the tsst genes was codon-optimized for expression in Escherichia coli and encoded a 26 kDa recombinant multidomain chimeric protein (r-TE). Hyperimmune antiserum raised against r-TE specifically reacted with SEB (~28 kDa) and Tsst-1 (~22 kDa) components during Western blot analysis and by plate ELISA in confirmed toxin producing strains of S. aureus. The antigenicity of the SEB component of the r-TE protein was also confirmed using TECRA kit. The described procedure of creating a single protein molecule carrying components of two different toxins whilst still retaining the original antigenic determinants of individual toxins proved highly advantageous in the development of rapid, reliable and cost effective immunoassays and may also have the potential to serve as candidate molecule for vaccine studies.
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Affiliation(s)
- R Shylaja
- Department of Microbiology, Defence Food Research Laboratory, Siddharthanagar, Mysore, 570011 India
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9
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Dang MH, Kato H, Ueshiba H, Omori-Miyake M, Yamagoe S, Ando K, Imanishi K, Arimura Y, Haruta I, Kotani T, Ozaki M, Suzuki K, Uchiyama T, Yagi J. Possible role of LECT2 as an intrinsic regulatory factor in SEA-induced toxicity in d-galactosamine-sensitized mice. Clin Immunol 2010; 137:311-21. [DOI: 10.1016/j.clim.2010.08.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2010] [Revised: 08/06/2010] [Accepted: 08/06/2010] [Indexed: 12/30/2022]
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10
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Therapeutic down-modulators of staphylococcal superantigen-induced inflammation and toxic shock. Toxins (Basel) 2010; 2:1963-83. [PMID: 22069668 PMCID: PMC3153276 DOI: 10.3390/toxins2081963] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Revised: 07/16/2010] [Accepted: 07/28/2010] [Indexed: 12/21/2022] Open
Abstract
Staphylococcal enterotoxin B (SEB) and related superantigenic toxins are potent stimulators of the immune system and cause a variety of diseases in humans, ranging from food poisoning to toxic shock. These toxins bind directly to 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 monocytes/macrophages and T lymphocytes. Activated host cells produce massive amounts of proinflammatory cytokines and chemokines, activating inflammation and coagulation, causing clinical symptoms that include fever, hypotension, and shock. This review summarizes the in vitro and in vivo effects of staphylococcal superantigens, the role of pivotal mediators induced by these toxins in the pathogenic mechanisms of tissue injury, and the therapeutic agents to mitigate the toxic effects of superantigens.
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11
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Kumar TDK, Balakrishna K, Murali HS, Batra HV. Construction of a recombinant intergenus multidomain chimeric protein for simultaneous expression of haemolysin BL of Bacillus cereus, listeriolysin O of Listeria monocytogenes and enterotoxin B of Staphylococcus aureus. J Med Microbiol 2009; 58:577-583. [PMID: 19369518 DOI: 10.1099/jmm.0.007658-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Haemolysin BL (HBL) of Bacillus cereus, listeriolysin O (LLO) of Listeria monocytogenes and enterotoxin B (SEB) of Staphylococcus aureus are among the major toxin components contributing to the pathogenicity of these organisms in foodborne illnesses. In this study, an intergenus non-toxic multidomain fusion protein (r-HLE) was generated with specificity for HBL, LLO and SEB. The fusion gene (r-hle) comprising the conserved regions of hblD and the hly and entB genes was codon-optimized for expression in Escherichia coli and encoded a 50 kDa recombinant multidomain chimeric protein (r-HLE). Hyperimmune antiserum raised against r-HLE specifically reacted with the L1 (38 kDa) component of the HBL complex of B. cereus, LLO (58 kDa) of L. monocytogenes and SEB (28 kDa) of S. aureus during Western blot analysis when tested on standard strains. During testing on isolates, the antiserum again identified the appropriate toxin molecules and was highly specific to the relevant bacterial species. The antigenicity of the SEB component of the r-HLE protein was also confirmed using a commercially available TECRA kit. The described procedure of creating a single antigenic molecule carrying components of three different toxins whilst still retaining the original antigenic determinants of individual toxins will be highly advantageous in the development of rapid, reliable and cost-effective immunoassays.
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Affiliation(s)
- T D Kalyan Kumar
- Division of Microbiology, Defense Food Research Laboratory, Siddhartha Nagar, Mysore, Karnataka 570011, India
| | - K Balakrishna
- Division of Microbiology, Defense Food Research Laboratory, Siddhartha Nagar, Mysore, Karnataka 570011, India
| | - H S Murali
- Division of Microbiology, Defense Food Research Laboratory, Siddhartha Nagar, Mysore, Karnataka 570011, India
| | - H V Batra
- Division of Microbiology, Defense Food Research Laboratory, Siddhartha Nagar, Mysore, Karnataka 570011, India
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Hayashida K, Chen Y, Bartlett AH, Park PW. Syndecan-1 is an in vivo suppressor of Gram-positive toxic shock. J Biol Chem 2008; 283:19895-903. [PMID: 18499671 DOI: 10.1074/jbc.m801614200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Heparan sulfate proteoglycans bind to and regulate many inflammatory mediators in vitro, suggesting that they serve an important role in influencing inflammatory responses in vivo. Here we evaluated the role of syndecan-1, a major heparan sulfate proteoglycan, in modulating inflammatory responses in Gram-positive toxic shock, a systemic disease that is a significant cause of morbidity and mortality. Syndecan-1-null and wild-type mice were injected intraperitoneally with staphylococcal enterotoxin B, a pyrogenic superantigen, and their inflammatory responses were assessed. Syndecan-1-null mice showed significantly increased liver injury, vascular permeability, and death in response to staphylococcal enterotoxin B challenge compared with wild-type mice. Although serum levels of systemic IL-2 and IFNgamma were similar between the two backgrounds, those of TNFalpha and IL-6 were significantly increased in syndecan-1-null mice undergoing Gram-positive toxic shock. Furthermore, syndecan-1-null mice challenged with staphylococcal enterotoxin B showed enhanced T cell accumulation in tissues, whereas immunodepletion of T cells protected syndecan-1-null mice from the magnified systemic cytokine storm, inflammatory tissue injury, and death. Importantly, syndecan-1 shedding was induced in wild-type mice injected with staphylococcal enterotoxin B, and the administration of heparan sulfate, but not syndecan-1 core protein, rescued syndecan-1-null mice from lethal toxic shock by suppressing the production of TNFalpha and IL-6, and attenuating inflammatory tissue injury. Altogether, these data suggest that syndecan-1 shedding is a key endogenous mechanism that protects the host from Gram-positive toxic shock by inhibiting the dysregulation and amplification of the inflammatory response.
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Affiliation(s)
- Kazutaka Hayashida
- Division of Respiratory Diseases, Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
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13
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A novel block to mouse mammary tumor virus infection of lymphocytes in B10.BR mice. J Virol 2007; 82:1314-22. [PMID: 18003725 DOI: 10.1128/jvi.01848-07] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Classic studies on C57BL-derived mouse strains showed that they were resistant to mouse mammary tumor virus (MMTV) infection. Although one form of resistance mapped to the major histocompatibility complex (MHC) locus, at least one other, unknown gene was implicated in this resistance. We show here that B10.BR mice, which are derived from C57BL mice but have the same MHC locus (H-2(k)) as susceptible C3H/HeN mice, are resistant to MMTV, and show a lack of virus spread in their lymphoid compartments but not their mammary epithelial cells. Although in vivo virus superantigen (Sag)-mediated activation of T cells was similar in C3H/HeN and B10.BR mice, T cell-dependent B-cell and dendritic cell activation was diminished in the latter. Ex vivo, B10.BR T cells showed a diminished capacity to proliferate in response to the MMTV Sag. The genetic segregation of the resistance phenotype indicated that it maps to a single allele. These data highlight the role of Sag-dependent T-cell responses in MMTV infection and point to a novel mechanism for the resistance of mice to retroviral infection that could lead to a better understanding of the interplay between hosts and pathogens.
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14
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Ragin MJ, Sahu N, August A. Differential regulation of cytokine production by CD1d-restricted NKT cells in response to superantigen staphylococcal enterotoxin B exposure. Infect Immun 2006; 74:282-8. [PMID: 16368982 PMCID: PMC1346674 DOI: 10.1128/iai.74.1.282-288.2006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
NKT cells are a heterogeneous population characterized by the ability to rapidly produce cytokines, such as interleukin 2 (IL-2), IL-4, and gamma interferon (IFN-gamma) in response to infections by viruses, bacteria, and parasites. The bacterial superantigen staphylococcal enterotoxin B (SEB) interacts with T cells bearing the Vbeta3, -7, or -8 T-cell receptors, inducing their expansion and cytokine secretion, leading to death in some cases due to cytokine poisoning. The majority of NKT cells bear the Vbeta7 or -8 T-cell receptor, suggesting that they may play a role in regulating this response. Using mice lacking NKT cells (CD1d(-/-) and Jalpha18(-/-) mice), we set out to identify the role of these cells in T-cell expansion, cytokine secretion, and toxicity induced by exposure to SEB. We find that Vbeta8(+) CD4(+) T-cell populations similarly expand in wild-type (WT) and NKT cell-null mice and that NKT cells did not regulate the secretion of IL-2. By contrast, these cells positively regulated the secretion of IL-4 and IFN-gamma production and negatively regulated the secretion of tumor necrosis factor alpha (TNF-alpha). However, this negative regulation of TNF-alpha secretion by NKT cells provides only a minor protective effect on SEB-mediated shock in WT mice compared to mice lacking NKT cells. These data suggest that NKT cells may regulate the nature of the cytokine response to exposure to the superantigen SEB and may act as regulatory T cells during exposure to this superantigen.
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MESH Headings
- Animals
- Antigens, CD1/genetics
- Antigens, CD1/metabolism
- Antigens, CD1/physiology
- Antigens, CD1d
- Cell Proliferation
- Cytokines/biosynthesis
- Enterotoxins/physiology
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Killer Cells, Natural/microbiology
- Mice
- Mice, Inbred BALB C
- Mice, Knockout
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- Staphylococcal Infections/immunology
- Staphylococcus aureus/immunology
- Superantigens/physiology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- T-Lymphocyte Subsets/microbiology
- T-Lymphocytes, Regulatory/immunology
- T-Lymphocytes, Regulatory/metabolism
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Affiliation(s)
- Melanie J Ragin
- Center for Molecular Immunology & Infectious Disease, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, 115 Henning Building, University Park, PA 16803, USA
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15
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Ragin MJ, Hu J, Henderson AJ, August A. A role for the Tec family kinase ITK in regulating SEB-induced interleukin-2 production in vivo via c-jun phosphorylation. BMC Immunol 2005; 6:19. [PMID: 16042784 PMCID: PMC1200558 DOI: 10.1186/1471-2172-6-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2004] [Accepted: 07/22/2005] [Indexed: 12/02/2022] Open
Abstract
Background Exposure to Staphylococcal Enterotoxin B (SEB), a bacterial superantigen secreted by the Gram-positive bacteria Staphyloccocus aureus, results in the expansion and eventual clonal deletion and anergy of Vβ8+ T cells, as well as massive cytokine release, including Interleukin-2 (IL-2). This IL-2 is rapidly secreted following exposure to SEB and may contribute to the symptoms seen following exposure to this bacterial toxin. The Tec family kinase ITK has been shown to be important for the production of IL-2 by T cells stimulated in vitro and may represent a good target for blocking the production of this cytokine in vivo. In order to determine if ITK represents such a target, mice lacking ITK were analyzed for their response to SEB exposure. Results It was found that T cells from mice lacking ITK exhibited significantly reduced proliferative responses to SEB exposure in vitro, as well as in vivo. Examination of IL-2 production revealed that ITK null mice produced reduced levels of this cytokine in vitro, and more dramatically, in vivo. In vivo analysis of c-jun phosphorylation, previously shown to be critical for regulating IL-2 production, revealed that this pathway was specifically activated in SEB reactive Vβ8+ (but not non-reactive Vβ6+) T cells from WT mice, but not in Vβ8+ T cells from ITK null mice. However, toxicity analysis indicated that both WT and ITK null animals were similarly affected by SEB exposure. Conclusion These data show that ITK is required for IL-2 production induced by SEB in vivo, and may regulate signals leading IL-2 production, in part by regulating phosphorylation of c-jun. The data also suggest that perturbing T cell activation pathways leading to IL-2 does not necessarily lead to improved responses to SEB toxicity.
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Affiliation(s)
- Melanie J Ragin
- Pathobiology Graduate Program, Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jianfang Hu
- Immunobiology Option of the Integrated Bioscience Graduate Program, Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science, The Pennsylvania State University, University Park, PA 16802, USA
| | - Andrew J Henderson
- Pathobiology Graduate Program, Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science, The Pennsylvania State University, University Park, PA 16802, USA
- Immunobiology Option of the Integrated Bioscience Graduate Program, Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science, The Pennsylvania State University, University Park, PA 16802, USA
- Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science The Pennsylvania State University, University Park, PA 16802, USA
| | - Avery August
- Pathobiology Graduate Program, Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science, The Pennsylvania State University, University Park, PA 16802, USA
- Immunobiology Option of the Integrated Bioscience Graduate Program, Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science, The Pennsylvania State University, University Park, PA 16802, USA
- Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science The Pennsylvania State University, University Park, PA 16802, USA
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16
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Yarovinsky TO, Mohning MP, Bradford MA, Monick MM, Hunninghake GW. Increased sensitivity to staphylococcal enterotoxin B following adenoviral infection. Infect Immun 2005; 73:3375-84. [PMID: 15908364 PMCID: PMC1111844 DOI: 10.1128/iai.73.6.3375-3384.2005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Staphylococcal enterotoxin B induces toxic shock and is a major virulence factor of staphylococcal diseases. We examined the effects of systemic adenoviral infection on responses to staphylococcal enterotoxin B in a murine model. We found that adenoviral infection markedly increases the severity of liver injury following exposure to staphylococcal enterotoxin B without d-galactosamine sensitization. In adenovirus-infected mice, staphylococcal enterotoxin B triggered a more profound hypothermia and increased apoptosis in the liver. Consistent with these observations, we also found that adenoviral infection primed for an increased production of gamma interferon in vivo and in vitro following stimulation with staphylococcal enterotoxin B. Gamma-interferon-knockout mice did not show increased sensitivity to staphylococcal enterotoxin B following adenoviral infection. These data suggest that a preexisting viral infection primes mice for subsequent staphylococcal enterotoxin B exposure, possibly via a gamma-interferon-mediated mechanism.
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Affiliation(s)
- Timur O Yarovinsky
- Division of Pulmonary, Critical Care, and Occupational Medicine, 100 EMRB, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA.
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17
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Grivennikov SI, Tumanov AV, Liepinsh DJ, Kruglov AA, Marakusha BI, Shakhov AN, Murakami T, Drutskaya LN, Förster I, Clausen BE, Tessarollo L, Ryffel B, Kuprash DV, Nedospasov SA. Distinct and nonredundant in vivo functions of TNF produced by t cells and macrophages/neutrophils: protective and deleterious effects. Immunity 2005; 22:93-104. [PMID: 15664162 DOI: 10.1016/j.immuni.2004.11.016] [Citation(s) in RCA: 156] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2004] [Revised: 11/06/2004] [Accepted: 11/24/2004] [Indexed: 11/16/2022]
Abstract
Tumor necrosis factor (TNF, TNFalpha) is implicated in various pathophysiological processes and can be either protective, as in host defense, or deleterious, as in autoimmunity or toxic shock. To uncover the in vivo functions of TNF produced by different cell types, we generated mice with TNF ablation targeted to various leukocyte subsets. Systemic TNF in response to lipopolysaccharide was produced mainly by macrophages and neutrophils. This source of TNF was indispensable for resistance to an intracellular pathogen, Listeria, whereas T-cell-derived TNF was important for protection against high bacterial load. Additionally, both T-cell-derived TNF and macrophage-derived TNF had critical and nonredundant functions in the promotion of autoimmune hepatitis. Our data suggest that T-cell-specific TNF ablation may provide a therapeutic advantage over systemic blockade.
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Affiliation(s)
- Sergei I Grivennikov
- Laboratory of Molecular Immunology, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences and Belozersky Institute of Physico-Chemical Biology, 32 Vavilov Str., 119991 Moscow, Russia
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18
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de Carvalho Uhl MV, Bottecchia RJ, Azevedo-Silva J, Antonio DL, Vieira-da-Motta O, Mittmann J, Ribeiro PD, de Souza Campos Fernandes RC, Távora N, Medina-Acosta E. Suitability of a recombinant Staphylococcus aureus enterotoxin C bovine variant for immunodiagnostics and therapeutic vaccine development. Vaccine 2004; 22:4191-202. [PMID: 15474709 DOI: 10.1016/j.vaccine.2004.05.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2003] [Accepted: 05/04/2004] [Indexed: 11/22/2022]
Abstract
Recombinant bovine variant of staphylococcal enterotoxin C (SECbovine), produced as a NH2-terminal histidine hexamer fusion protein (His6-tagged SECbovine), expressed at high levels (25%) in Escherichia coli and affinity purified to homogeneity (99.9%), was tested for its diagnostic and therapeutic potentials. His6-tagged SECbovine is antigenically authentic to native SECbovine across host species, as confirmed by antibody-based capture detection assays using human, mouse, rabbit and chicken hyperimmune sera. His6-tagged SECbovine showed significant T-cell stimulation activity in vitro. His6-tagged SECbovine was immunogenic for IgG in mice (intragastric and intravenous routes) and rabbits (intramuscular and subcutaneous routes), dispensing immunoadjuvant coadministration. The formation of neutralizing antibodies reduced the severity of intoxication symptoms in immunized rabbits. Purified anti-recombinant SECbovine rabbit polyclonal IgG neutralized the pyrexic and diarrhoeagenic effects of native SEC/SED and recombinant SEC, tested by the kitten and rabbit bioassays, respectively.
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Affiliation(s)
- Marcelle Vianna de Carvalho Uhl
- Laboratório de Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego 2000, Parque Califórnia, CEP 28013-602 Campos dos Goytacazes, RJ, Brazil
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19
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Savransky V, Rostapshov V, Pinelis D, Polotsky Y, Korolev S, Komisar J, Fegeding K. Murine lethal toxic shock caused by intranasal administration of staphylococcal enterotoxin B. Toxicol Pathol 2003; 31:373-8. [PMID: 12851102 DOI: 10.1080/01926230390201093] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Currently available murine staphylococcal enterotoxin B (SEB) shock models require pretreatment with various agents to increase mouse sensitivity to SEB. This study was performed to show that C3H/HeJ mice are highly susceptible to intranasal SEB inoculation, which caused toxic shock without using pretreatment agents. For this purpose, mice were injected intranasally with different doses of SEB and observed for up to 1 month. The median lethal dose of SEB was determined using the probit procedure. Tissue samples were taken at different time points for histopathological examination. The LD(50) was found at 1.6 microg/g (95% fiducial limit (f.l.) 0.7 to 2.2), the LD(80) at 2.7 microg/g (95% f.l. 1.9 to 4.0) and the LD(90) at 3.6 microg/g (95% f.l. 2.7 to 6.4). Histopathologic examination revealed pulmonary edema and bronchopneumonia. Mucosal-associated lymphoid tissue first became activated, followed by increasing lymphocyte apoptosis and depletion. In the liver there were intralobular and portal inflammatory foci with increasing lymphocyte apoptosis and degenerative necrosis. The splenic white pulp was characterized by early activation and subsequent depletion of lymphoid follicle germinal centers. The thymus initially was activated, followed by increasing apoptosis and migration of lymphoid cells from the cortex to the medulla. The pathological features detected in the mice were similar to those of rhesus monkeys treated with SEB aerosol challenge.
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Affiliation(s)
- Vladimir Savransky
- Department of Experimental Pathology, Division of Pathology, Walter Reed Army Institute of Research, Silver Spring, Maryland 20910, USA
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20
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Korolev S, Pinelis D, Savransky V, Komisar J, Vogel P, Fegeding K. Toxicity of the staphylococcal enterotoxin B mutants with histidine-to-tyrosine substitutions. Toxicology 2003; 187:229-38. [PMID: 12699911 DOI: 10.1016/s0300-483x(03)00049-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
In this study we made a series of site-directed mutants of staphylococcal enterotoxin B (SEB), in which histidine residues in the molecule were replaced by tyrosine. The mutant genes were cloned and expressed, and the corresponding proteins were purified. These mutant proteins were tested for binding to human HLA-DR4 and for mitogenetic activity in mouse splenocyte culture. Toxicity of the proteins in vivo was evaluated in the actinomycin D-primed C3H/HeJ mouse model. We found that SEB mutant proteins with fewer than four histidine-to-tyrosine (his-to-tyr) substitutions retained toxic properties similar to wild-type SEB. However, studies showed that his-to-tyr substitution of four consecutive histidine residues eliminated SEB toxicity. Our results clearly show that this genetically modified SEB protein is non-toxic and justifies its further development as a component of a new, safer vaccine to prevent SEB intoxication.
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Affiliation(s)
- Sergey Korolev
- Division of Pathology, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910-7500, USA
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21
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Rajagopalan G, Smart MK, Krco CJ, David CS. Expression and function of transgenic HLA-DQ molecules and lymphocyte development in mice lacking invariant chain. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 169:1774-83. [PMID: 12165499 DOI: 10.4049/jimmunol.169.4.1774] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Invariant chain (Ii) is a non-MHC-encoded molecule, which plays an accessory role in the proper assembly/expression of functional MHC class II molecules and there by plays an important role in Ag processing/presentation. The phenotype of mice lacking Ii depends on the allotype of the MHC class II molecule. In some mice strains, Ii deficiency results in reduction in expression of class II molecules accompanied by defective CD4(+) T cell development. Responses to conventional Ags/superantigens are also compromised. In this study, we describe for the first time the functionality of human class II molecules, HLA-DQ6 and HLA-DQ8, in transgenic mice lacking Ii. HLA transgenic Ii(-/-) mice expressed very low levels of surface DQ6 and DQ8 accompanied by severe reduction in CD4(+) T cells both in the thymus and periphery. In vitro proliferation and cytokine production to an exogenous superantigen, staphylococcal enterotoxin B (SEB) was diminished in HLA-transgenic Ii(-/-) mice. However, SEB-induced in vivo expansion of CD8(+) T cells expressing TCR Vbeta8 family in DQ8.Ii(-/-) mice was comparable with that of DQ8.Ii(+/+) mice. Systemic IFN-gamma production following in vivo challenge with SEB was reduced in DQ8.Ii(-/-) mice and were also protected from SEB-induced toxic shock. Although the T cell response to a known peptide Ag was diminished in DQ8.Ii(-/-) mice, DQ8.Ii(-/-) APCs were capable of presenting that peptide to primed T cells from wild-type DQ8 mice as well as to a specific T cell hybridoma. Differentiation of mature B cells was also affected to a certain extent in DQ8.Ii(-/-) mice.
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MESH Headings
- Animals
- Antigen Presentation
- Antigens/administration & dosage
- Antigens, Differentiation, B-Lymphocyte/genetics
- Antigens, Differentiation, B-Lymphocyte/metabolism
- B-Lymphocytes/cytology
- B-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/cytology
- CD4-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/cytology
- CD8-Positive T-Lymphocytes/immunology
- Cell Differentiation
- Cytoskeletal Proteins
- Enterotoxins/immunology
- Enterotoxins/toxicity
- Gene Expression
- HLA-DQ Antigens/genetics
- HLA-DQ Antigens/metabolism
- Histocompatibility Antigens Class II/genetics
- Histocompatibility Antigens Class II/metabolism
- Humans
- In Vitro Techniques
- Interferon-gamma/biosynthesis
- Lymphocyte Activation
- Lymphocyte Subsets/cytology
- Lymphocyte Subsets/immunology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Shock, Septic/etiology
- Shock, Septic/genetics
- Shock, Septic/immunology
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22
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Collins LV, Eriksson K, Ulrich RG, Tarkowski A. Mucosal tolerance to a bacterial superantigen indicates a novel pathway to prevent toxic shock. Infect Immun 2002; 70:2282-7. [PMID: 11953361 PMCID: PMC127931 DOI: 10.1128/iai.70.5.2282-2287.2002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enterotoxins with superantigenic properties secreted during systemic Staphylococcus aureus infection are responsible for toxic shock. We show that intranasal administration of staphylococcal enterotoxin A (SEA), but not a recombinant SEA lacking superantigenic activity, protected mice against lethal systemic SEA challenge. Protection was superantigen specific since intranasal exposure to SEA would not protect against death caused by subsequent toxic shock syndrome toxin 1 systemic challenge. Protection was neither due to selective depletion of SEA-specific T-cell receptor Vbeta families nor due to production of neutralizing anti-SEA antibodies. Importantly, the production of interleukin 10 (IL-10) induced by "tolerization" (that is, by the induction of immunological tolerance) contributed to the observed protection against lethal superantigen-triggered disease. In support of this notion we found that (i) significantly increased levels of IL-10 in sera of "tolerized" animals (that is, animals rendered tolerant) and (ii) IL-10(-/-) mice could not be tolerized by mucosal SEA administration. Altogether, this is the first study to show that mucosal tolerance to a superantigen is readily triggered by means of immunodeviation.
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Affiliation(s)
- L Vincent Collins
- Department of Rheumatology, University of Göteborg, Göteborg, Sweden.
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