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Sample records for anthrax edema toxin

  1. Transcriptional Stimulation of Anthrax Toxin Receptors by Anthrax Edema Toxin and Bacillus anthracis Sterne Spore

    PubMed Central

    Xu, Qingfu; Hesek, Eric D.; Zeng, Mingtao

    2007-01-01

    We used quantitative real-time RT-PCR to not only investigate the mRNA levels of anthrax toxin receptor 1 (ANTXR1) and 2 (ANTXR2) in the murine J774A.1 macrophage cells and different tissues of mice, but also evaluate the effect of anthrax edema toxin and Bacillus anthracis Sterne spores on the expression of mRNA of these receptors. The mRNA transcripts of both receptors was detected in J774A.1 cells and mouse tissues such as the lung, heart, kidney, spleen, stomach, jejunum, brain, skeleton muscle, and skin. The ANTXR2 mRNA level was significantly higher than that of ANTXR1 in J774A.1 cells and all tissues examined. The mRNA expression of both receptors in the lung was the highest among the tissues evaluated. Interestingly, the mRNA expression of both receptors in J774A.1 cells was up-regulated by edema toxin. In addition, ANTXR mRNA expression in the lung was down-regulated after subcutaneous inoculation of B. anthracis Sterne spores as well as after intranasal administration of anthrax toxin-based vaccine BioThrax™. These results suggest that anthrax edema toxin and B. anthracis Sterne spore are involved in the ANTXR mRNA regulation in host cells. PMID:17459655

  2. In situ gastrointestinal protection against anthrax edema toxin by single-chain antibody fragment producing lactobacilli

    PubMed Central

    2011-01-01

    Background Anthrax is caused by the bacterium Bacillus anthracis and is regarded as one of the most prominent bioterrorism threats. Anthrax toxicity is induced by the tripartite toxin complex, composed of the receptor-binding anthrax protective antigen and the two enzymatic subunits, lethal factor and edema factor. Recombinant lactobacilli have previously been used to deliver antibody fragments directed against surface epitopes of a variety of pathogens, including Streptococcus mutans, Porphyromonas gingivalis, and rotavirus. Here, we addressed whether or not anthrax toxins could be targeted and neutralised in the gastrointestinal tract by lactobacilli producing recombinant antibody fragments as a model system for toxin neutralisation in the gastrointestinal lumen. Results The neutralising anti-PA scFv, 1H, was expressed in L. paracasei as a secreted protein, a cell wall-anchored protein or both secreted and wall-anchored protein. Cell wall display on lactobacilli and PA binding of the anchored constructs was confirmed by flow cytometry analysis. Binding of secreted or attached scFv produced by lactobacilli to PA were verified by ELISA. Both construct were able to protect macrophages in an in vitro cytotoxicity assay. Finally, lactobacilli producing the cell wall attached scFv were able to neutralise the activity of anthrax edema toxin in the GI tract of mice, in vivo. Conclusion We have developed lactobacilli expressing a neutralising scFv fragment against the PA antigen of the anthrax toxin, which can provide protection against anthrax toxins both in vitro and in vivo. Utilising engineered lactobacilli therapeutically for neutralising toxins in the gastrointestinal tract can potential be expanded to provide protection against a range of additional gastrointestinal pathogens. The ability of lactobacilli to colonise the gastrointestinal tract may allow the system to be used both prophylactically and therapeutically. PMID:22185669

  3. The Potential Contributions of Lethal and Edema Toxins to the Pathogenesis of Anthrax Associated Shock

    PubMed Central

    Hicks, Caitlin W.; Cui, Xizhong; Sweeney, Daniel A.; Li, Yan; Barochia, Amisha; Eichacker, Peter Q.

    2011-01-01

    Outbreaks of Bacillus anthracis in the US and Europe over the past 10 years have emphasized the health threat this lethal bacteria poses even for developed parts of the world. In contrast to cutaneous anthrax, inhalational disease in the US during the 2001 outbreaks and the newly identified injectional drug use form of disease in the UK and Germany have been associated with relatively high mortality rates. One notable aspect of these cases has been the difficulty in supporting patients once shock has developed. Anthrax bacilli produce several different components which likely contribute to this shock. Growing evidence indicates that both major anthrax toxins may produce substantial cardiovascular dysfunction. Lethal toxin (LT) can alter peripheral vascular function; it also has direct myocardial depressant effects. Edema toxin (ET) may have even more pronounced peripheral vascular effects than LT, including the ability to interfere with the actions of conventional vasopressors. Additionally, ET also appears capable of interfering with renal sodium and water retention. Importantly, the two toxins exert their actions via quite different mechanisms and therefore have the potential to worsen shock and outcome in an additive fashion. Finally, both toxins have the ability to inhibit host defense and microbial clearance, possibly contributing to the very high bacterial loads noted in patients dying with anthrax. This last point is clinically relevant since emerging data has begun to implicate other bacterial components such as anthrax cell wall in the shock and organ injury observed with infection. Taken together, accumulating evidence regarding the potential contribution of LT and ET to anthrax-associated shock supports efforts to develop adjunctive therapies that target both toxins in patients with progressive shock. PMID:22069762

  4. Noninvasive Imaging Technologies Reveal Edema Toxin as a Key Virulence Factor in Anthrax

    PubMed Central

    Dumetz, Fabien; Jouvion, Grégory; Khun, Huot; Glomski, Ian Justin; Corre, Jean-Philippe; Rougeaux, Clémence; Tang, Wei-Jen; Mock, Michèle; Huerre, Michel; Goossens, Pierre Louis

    2011-01-01

    Powerful noninvasive imaging technologies enable real-time tracking of pathogen-host interactions in vivo, giving access to previously elusive events. We visualized the interactions between wild-type Bacillus anthracis and its host during a spore infection through bioluminescence imaging coupled with histology. We show that edema toxin plays a central role in virulence in guinea pigs and during inhalational infection in mice. Edema toxin (ET), but not lethal toxin (LT), markedly modified the patterns of bacterial dissemination leading, to apparent direct dissemination to the spleen and provoking apoptosis of lymphoid cells. Each toxin alone provoked particular histological lesions in the spleen. When ET and LT are produced together during infection, a specific temporal pattern of lesion developed, with early lesions typical of LT, followed at a later stage by lesions typical of ET. Our study provides new insights into the complex spatial and temporal effects of B. anthracis toxins in the infected host, suggesting a greater role than previously suspected for ET in anthrax and suggesting that therapeutic targeting of ET contributes to protection. PMID:21641378

  5. Tumor Targeting and Drug Delivery by Anthrax Toxin

    PubMed Central

    Bachran, Christopher; Leppla, Stephen H.

    2016-01-01

    Anthrax toxin is a potent tripartite protein toxin from Bacillus anthracis. It is one of the two virulence factors and causes the disease anthrax. The receptor-binding component of the toxin, protective antigen, needs to be cleaved by furin-like proteases to be activated and to deliver the enzymatic moieties lethal factor and edema factor to the cytosol of cells. Alteration of the protease cleavage site allows the activation of the toxin selectively in response to the presence of tumor-associated proteases. This initial idea of re-targeting anthrax toxin to tumor cells was further elaborated in recent years and resulted in the design of many modifications of anthrax toxin, which resulted in successful tumor therapy in animal models. These modifications include the combination of different toxin variants that require activation by two different tumor-associated proteases for increased specificity of toxin activation. The anthrax toxin system has proved to be a versatile system for drug delivery of several enzymatic moieties into cells. This highly efficient delivery system has recently been further modified by introducing ubiquitin as a cytosolic cleavage site into lethal factor fusion proteins. This review article describes the latest developments in this field of tumor targeting and drug delivery. PMID:27376328

  6. Tumor Targeting and Drug Delivery by Anthrax Toxin.

    PubMed

    Bachran, Christopher; Leppla, Stephen H

    2016-01-01

    Anthrax toxin is a potent tripartite protein toxin from Bacillus anthracis. It is one of the two virulence factors and causes the disease anthrax. The receptor-binding component of the toxin, protective antigen, needs to be cleaved by furin-like proteases to be activated and to deliver the enzymatic moieties lethal factor and edema factor to the cytosol of cells. Alteration of the protease cleavage site allows the activation of the toxin selectively in response to the presence of tumor-associated proteases. This initial idea of re-targeting anthrax toxin to tumor cells was further elaborated in recent years and resulted in the design of many modifications of anthrax toxin, which resulted in successful tumor therapy in animal models. These modifications include the combination of different toxin variants that require activation by two different tumor-associated proteases for increased specificity of toxin activation. The anthrax toxin system has proved to be a versatile system for drug delivery of several enzymatic moieties into cells. This highly efficient delivery system has recently been further modified by introducing ubiquitin as a cytosolic cleavage site into lethal factor fusion proteins. This review article describes the latest developments in this field of tumor targeting and drug delivery. PMID:27376328

  7. The Ins and Outs of Anthrax Toxin

    PubMed Central

    Friebe, Sarah; van der Goot, F. Gisou; Bürgi, Jérôme

    2016-01-01

    Anthrax is a severe, although rather rare, infectious disease that is caused by the Gram-positive, spore-forming bacterium Bacillus anthracis. The infectious form is the spore and the major virulence factors of the bacterium are its poly-γ-D-glutamic acid capsule and the tripartite anthrax toxin. The discovery of the anthrax toxin receptors in the early 2000s has allowed in-depth studies on the mechanisms of anthrax toxin cellular entry and translocation from the endocytic compartment to the cytoplasm. The toxin generally hijacks the endocytic pathway of CMG2 and TEM8, the two anthrax toxin receptors, in order to reach the endosomes. From there, the pore-forming subunit of the toxin inserts into endosomal membranes and enables translocation of the two catalytic subunits. Insertion of the pore-forming unit preferentially occurs in intraluminal vesicles rather than the limiting membrane of the endosome, leading to the translocation of the enzymatic subunits in the lumen of these vesicles. This has important consequences that will be discussed. Ultimately, the toxins reach the cytosol where they act on their respective targets. Target modification has severe consequences on cell behavior, in particular on cells of the immune system, allowing the spread of the bacterium, in severe cases leading to host death. Here we will review the literature on anthrax disease with a focus on the structure of the toxin, how it enters cells and its immunological effects. PMID:26978402

  8. The Ins and Outs of Anthrax Toxin.

    PubMed

    Friebe, Sarah; van der Goot, F Gisou; Bürgi, Jérôme

    2016-03-01

    Anthrax is a severe, although rather rare, infectious disease that is caused by the Gram-positive, spore-forming bacterium Bacillus anthracis. The infectious form is the spore and the major virulence factors of the bacterium are its poly-γ-D-glutamic acid capsule and the tripartite anthrax toxin. The discovery of the anthrax toxin receptors in the early 2000s has allowed in-depth studies on the mechanisms of anthrax toxin cellular entry and translocation from the endocytic compartment to the cytoplasm. The toxin generally hijacks the endocytic pathway of CMG2 and TEM8, the two anthrax toxin receptors, in order to reach the endosomes. From there, the pore-forming subunit of the toxin inserts into endosomal membranes and enables translocation of the two catalytic subunits. Insertion of the pore-forming unit preferentially occurs in intraluminal vesicles rather than the limiting membrane of the endosome, leading to the translocation of the enzymatic subunits in the lumen of these vesicles. This has important consequences that will be discussed. Ultimately, the toxins reach the cytosol where they act on their respective targets. Target modification has severe consequences on cell behavior, in particular on cells of the immune system, allowing the spread of the bacterium, in severe cases leading to host death. Here we will review the literature on anthrax disease with a focus on the structure of the toxin, how it enters cells and its immunological effects. PMID:26978402

  9. Roles of Anthrax Toxin Receptor 2 in Anthrax Toxin Membrane Insertion and Pore Formation

    PubMed Central

    Sun, Jianjun; Jacquez, Pedro

    2016-01-01

    Interaction between bacterial toxins and cellular surface receptors is an important component of the host-pathogen interaction. Anthrax toxin protective antigen (PA) binds to the cell surface receptor, enters the cell through receptor-mediated endocytosis, and forms a pore on the endosomal membrane that translocates toxin enzymes into the cytosol of the host cell. As the major receptor for anthrax toxin in vivo, anthrax toxin receptor 2 (ANTXR2) plays an essential role in anthrax toxin action by providing the toxin with a high-affinity binding anchor on the cell membrane and a path of entry into the host cell. ANTXR2 also acts as a molecular clamp by shifting the pH threshold of PA pore formation to a more acidic pH range, which prevents premature pore formation at neutral pH before the toxin reaches the designated intracellular location. Most recent studies have suggested that the disulfide bond in the immunoglobulin (Ig)-like domain of ANTXR2 plays an essential role in anthrax toxin action. Here we will review the roles of ANTXR2 in anthrax toxin action, with an emphasis on newly updated knowledge. PMID:26805886

  10. Roles of Anthrax Toxin Receptor 2 in Anthrax Toxin Membrane Insertion and Pore Formation.

    PubMed

    Sun, Jianjun; Jacquez, Pedro

    2016-02-01

    Interaction between bacterial toxins and cellular surface receptors is an important component of the host-pathogen interaction. Anthrax toxin protective antigen (PA) binds to the cell surface receptor, enters the cell through receptor-mediated endocytosis, and forms a pore on the endosomal membrane that translocates toxin enzymes into the cytosol of the host cell. As the major receptor for anthrax toxin in vivo, anthrax toxin receptor 2 (ANTXR2) plays an essential role in anthrax toxin action by providing the toxin with a high-affinity binding anchor on the cell membrane and a path of entry into the host cell. ANTXR2 also acts as a molecular clamp by shifting the pH threshold of PA pore formation to a more acidic pH range, which prevents premature pore formation at neutral pH before the toxin reaches the designated intracellular location. Most recent studies have suggested that the disulfide bond in the immunoglobulin (Ig)-like domain of ANTXR2 plays an essential role in anthrax toxin action. Here we will review the roles of ANTXR2 in anthrax toxin action, with an emphasis on newly updated knowledge. PMID:26805886

  11. Anthrax toxin-induced rupture of artificial lipid bilayer membranes.

    PubMed

    Nablo, Brian J; Panchal, Rekha G; Bavari, Sina; Nguyen, Tam L; Gussio, Rick; Ribot, Wil; Friedlander, Art; Chabot, Donald; Reiner, Joseph E; Robertson, Joseph W F; Balijepalli, Arvind; Halverson, Kelly M; Kasianowicz, John J

    2013-08-14

    We demonstrate experimentally that anthrax toxin complexes rupture artificial lipid bilayer membranes when isolated from the blood of infected animals. When the solution pH is temporally acidified to mimic that process in endosomes, recombinant anthrax toxin forms an irreversibly bound complex, which also destabilizes membranes. The results suggest an alternative mechanism for the translocation of anthrax toxin into the cytoplasm. PMID:23947891

  12. Anthrax toxin-induced rupture of artificial lipid bilayer membranes

    NASA Astrophysics Data System (ADS)

    Nablo, Brian J.; Panchal, Rekha G.; Bavari, Sina; Nguyen, Tam L.; Gussio, Rick; Ribot, Wil; Friedlander, Art; Chabot, Donald; Reiner, Joseph E.; Robertson, Joseph W. F.; Balijepalli, Arvind; Halverson, Kelly M.; Kasianowicz, John J.

    2013-08-01

    We demonstrate experimentally that anthrax toxin complexes rupture artificial lipid bilayer membranes when isolated from the blood of infected animals. When the solution pH is temporally acidified to mimic that process in endosomes, recombinant anthrax toxin forms an irreversibly bound complex, which also destabilizes membranes. The results suggest an alternative mechanism for the translocation of anthrax toxin into the cytoplasm.

  13. Quantitative Determination of Lethal Toxin Proteins in Culture Supernatant of Human Live Anthrax Vaccine Bacillus anthracis A16R.

    PubMed

    Zai, Xiaodong; Zhang, Jun; Liu, Ju; Liu, Jie; Li, Liangliang; Yin, Ying; Fu, Ling; Xu, Junjie; Chen, Wei

    2016-03-01

    Bacillus anthracis (B. anthracis) is the etiological agent of anthrax affecting both humans and animals. Anthrax toxin (AT) plays a major role in pathogenesis. It includes lethal toxin (LT) and edema toxin (ET), which are formed by the combination of protective antigen (PA) and lethal factor (LF) or edema factor (EF), respectively. The currently used human anthrax vaccine in China utilizes live-attenuated B. anthracis spores (A16R; pXO1+, pXO2-) that produce anthrax toxin but cannot produce the capsule. Anthrax toxins, especially LT, have key effects on both the immunogenicity and toxicity of human anthrax vaccines. Thus, determining quantities and biological activities of LT proteins expressed by the A16R strain is meaningful. Here, we explored LT expression patterns of the A16R strain in culture conditions using another vaccine strain Sterne as a control. We developed a sandwich ELISA and cytotoxicity-based method for quantitative detection of PA and LF. Expression and degradation of LT proteins were observed in culture supernatants over time. Additionally, LT proteins expressed by the A16R and Sterne strains were found to be monomeric and showed cytotoxic activity, which may be the main reason for side effects of live anthrax vaccines. Our work facilitates the characterization of anthrax vaccines components and establishment of a quality control standard for vaccine production which may ultimately help to ensure the efficacy and safety of the human anthrax vaccine A16R. PMID:26927174

  14. Quantitative Determination of Lethal Toxin Proteins in Culture Supernatant of Human Live Anthrax Vaccine Bacillus anthracis A16R

    PubMed Central

    Zai, Xiaodong; Zhang, Jun; Liu, Ju; Liu, Jie; Li, Liangliang; Yin, Ying; Fu, Ling; Xu, Junjie; Chen, Wei

    2016-01-01

    Bacillus anthracis (B. anthracis) is the etiological agent of anthrax affecting both humans and animals. Anthrax toxin (AT) plays a major role in pathogenesis. It includes lethal toxin (LT) and edema toxin (ET), which are formed by the combination of protective antigen (PA) and lethal factor (LF) or edema factor (EF), respectively. The currently used human anthrax vaccine in China utilizes live-attenuated B. anthracis spores (A16R; pXO1+, pXO2−) that produce anthrax toxin but cannot produce the capsule. Anthrax toxins, especially LT, have key effects on both the immunogenicity and toxicity of human anthrax vaccines. Thus, determining quantities and biological activities of LT proteins expressed by the A16R strain is meaningful. Here, we explored LT expression patterns of the A16R strain in culture conditions using another vaccine strain Sterne as a control. We developed a sandwich ELISA and cytotoxicity-based method for quantitative detection of PA and LF. Expression and degradation of LT proteins were observed in culture supernatants over time. Additionally, LT proteins expressed by the A16R and Sterne strains were found to be monomeric and showed cytotoxic activity, which may be the main reason for side effects of live anthrax vaccines. Our work facilitates the characterization of anthrax vaccines components and establishment of a quality control standard for vaccine production which may ultimately help to ensure the efficacy and safety of the human anthrax vaccine A16R. PMID:26927174

  15. Molecular Motions as a Drug Target: Mechanistic Simulations of Anthrax Toxin Edema Factor Function Led to the Discovery of Novel Allosteric Inhibitors

    PubMed Central

    Laine, Élodie; Martínez, Leandro; Ladant, Daniel; Malliavin, Thérèse; Blondel, Arnaud

    2012-01-01

    Edema Factor (EF) is a component of Bacillus anthracis toxin essential for virulence. Its adenylyl cyclase activity is induced by complexation with the ubiquitous eukaryotic cellular protein, calmodulin (CaM). EF and its complexes with CaM, nucleotides and/or ions, have been extensively characterized by X-ray crystallography. Those structural data allowed molecular simulations analysis of various aspects of EF action mechanism, including the delineation of EF and CaM domains through their association energetics, the impact of calcium binding on CaM, and the role of catalytic site ions. Furthermore, a transition path connecting the free inactive form to the CaM-complexed active form of EF was built to model the activation mechanism in an attempt to define an inhibition strategy. The cavities at the surface of EF were determined for each path intermediate to identify potential sites where the binding of a ligand could block activation. A non-catalytic cavity (allosteric) was found to shrink rapidly at early stages of the path and was chosen to perform virtual screening. Amongst 18 compounds selected in silico and tested in an enzymatic assay, 6 thiophen ureidoacid derivatives formed a new family of EF allosteric inhibitors with IC50 as low as 2 micromolars. PMID:23012649

  16. Novel inhibitors of Anthrax edema factor

    PubMed Central

    Chen, Deliang; Misra, Milind; Sower, Laurie; Peterson, Johnny W.; Kellogg, Glen E.; Schein, Catherine H.

    2008-01-01

    Several pathogenic bacteria produce adenylyl cyclase toxins, such as the edema factor (EF) of Bacillus anthracis. These disturb cellular metabolism by catalyzing production of excessive amounts of the regulatory molecule cAMP. Here, a structure-based method, where a 3D- pharmacophore that fit the active site of EF was constructed from fragments, was used to identify non-nucleotide inhibitors of EF. A library of small molecule fragments was docked to the EF- active site in existing crystal structures and those with the highest HINT scores were assembled into a 3D-pharmacophore. About 10,000 compounds, from over 2.7 million compounds in the ZINC database, had a similar molecular framework. These were ranked according to their docking scores, using methodology that was shown to achieve maximum accuracy (i.e., how well the docked position matched the experimentally determined site for ATP analogues in crystal structures of the complex). Finally, 19 diverse compounds with the best AutoDock binding/docking scores were assayed in a cell based assay for their ability to reduce cAMP secretion induced by EF. Four of the test compounds, from different structural groups, inhibited in the low micromolar range. One of these has a core structure common to phosphatase inhibitors previously identified by high-throughput assays of a diversity library. Thus, the fragment based pharmacophore identified a small number of diverse compounds for assay, and greatly enhanced the selection process of advanced lead compounds for combinatorial design. PMID:18620864

  17. Ratcheting up protein translocation with anthrax toxin

    PubMed Central

    Feld, Geoffrey K; Brown, Michael J; Krantz, Bryan A

    2012-01-01

    Energy-consuming nanomachines catalyze the directed movement of biopolymers in the cell. They are found both dissolved in the aqueous cytosol as well as embedded in lipid bilayers. Inquiries into the molecular mechanism of nanomachine-catalyzed biopolymer transport have revealed that these machines are equipped with molecular parts, including adjustable clamps, levers, and adaptors, which interact favorably with substrate polypeptides. Biological nanomachines that catalyze protein transport, known as translocases, often require that their substrate proteins unfold before translocation. An unstructured protein chain is likely entropically challenging to bind, push, or pull in a directional manner, especially in a way that produces an unfolding force. A number of ingenious solutions to this problem are now evident in the anthrax toxin system, a model used to study protein translocation. Here we highlight molecular ratchets and current research on anthrax toxin translocation. A picture is emerging of proton-gradient-driven anthrax toxin translocation, and its associated ratchet mechanism likely applies broadly to other systems. We suggest a cyclical thermodynamic order-to-disorder mechanism (akin to a heat-engine cycle) is central to underlying protein translocation: peptide substrates nonspecifically bind to molecular clamps, which possess adjustable affinities; polypeptide substrates compress into helical structures; these clamps undergo proton-gated switching; and the substrate subsequently expands regaining its unfolded state conformational entropy upon translocation. PMID:22374876

  18. New insights into the biological effects of anthrax toxins: linking cellular to organismal responses

    PubMed Central

    Guichard, Annabel; Nizet, Victor; Bier, Ethan

    2013-01-01

    The anthrax toxins lethal toxin (LT) and edema toxin (ET), are essential virulence factors produced by B. anthracis. These toxins act during two distinct phases of anthrax infection. During the first, prodromal phase, which is often asymptomatic, anthrax toxins act on cells of the immune system to help the pathogen establish infection. Then, during the rapidly progressing (or fulminant) stage of the disease bacteria disseminate via a hematological route to various target tissues and organs, which are typically highly vascularized. As bacteria proliferate in the bloodstream LT and ET begin to accumulate rapidly reaching a critical threshold level that will cause death even when the bacterial proliferation is curtailed by antibiotics. During this final phase of infection the toxins cause an increase in vascular permeability and a decrease in function of target organs including the heart, spleen, kidney, adrenal gland, and brain. In this review, we examine the various biological effects of anthrax toxins, focusing on the fulminant stage of the disease and on mechanisms by which the two toxins may collaborate to cause cardiovascular collapse. We discuss normal mechanisms involved in maintaining vascular integrity and based on recent studies indicating that LT and ET cooperatively inhibit membrane trafficking to cell-cell junctions we explore several potential mechanisms by which the toxins may achieve their lethal effects. We also summarize the effects of other potential virulence factors secreted by B. anthracis and consider the role of toxic factors in the evolutionarily recent emergence of this devastating disease. PMID:21930233

  19. Atomic structure of anthrax PA pore elucidates toxin translocation

    PubMed Central

    Jiang, Jiansen; Pentelute, Bradley L.; Collier, R. John; Zhou, Z. Hong

    2015-01-01

    Summary Anthrax toxin, comprising protective antigen (PA), lethal factor (LF) and edema factor (EF), is the major virulence factor of Bacillus anthracis, an agent that causes high mortality in human and animals. PA forms oligomeric prepores that undergo conversion to membrane-spanning pores by endosomal acidification, and these pores translocate the enzymes LF and EF into the cytosol of target cells1. PA is not only a vaccine component and therapeutic target for anthrax infections but also an excellent model system for understanding the mechanism of protein translocation. Based on biochemical and electrophysiological results, researchers have proposed that a Φ-clamp composed of Phe427 residues of PA catalyzes protein translocation via a charge-state dependent Brownian ratchet2–9. Although atomic structures of PA prepores are available10–14, how PA senses low pH, converts to active pore and translocates LF and EF are not well defined without an atomic model of the PA pore. Here, by cryo electron microscopy (cryoEM) with direct electron counting, we have determined the PA pore structure at 2.9-Å resolution. The structure reveals the long-sought-after catalytic Φ-clamp and the membrane-spanning translocation channel, and supports the Brownian ratchet model for protein translocation. Comparisons of four structures reveal conformational changes in prepore to pore conversion that support a multi-step mechanism by which low-pH is sensed and the membrane-spanning channel is formed. PMID:25778700

  20. In vivo dynamics of active edema and lethal factors during anthrax

    PubMed Central

    Rougeaux, Clémence; Becher, François; Ezan, Eric; Tournier, Jean-Nicolas; Goossens, Pierre L.

    2016-01-01

    Lethal and edema toxins are critical virulence factors of Bacillus anthracis. However, little is known about their in vivo dynamics of production during anthrax. In this study, we unraveled for the first time the in vivo kinetics of production of the toxin components EF (edema factor) and LF (lethal factor) during cutaneous infection with a wild-type toxinogenic encapsulated strain in immuno-competent mice. We stratified the asynchronous infection process into defined stages through bioluminescence imaging (BLI), while exploiting sensitive quantitative methods by measuring the enzymatic activity of LF and EF. LF was produced in high amounts, while EF amounts steadily increased during the infectious process. This led to high LF/EF ratios throughout the infection, with variations between 50 to a few thousands. In the bloodstream, the early detection of active LF and EF despite the absence of bacteria suggests that they may exert long distance effects. Infection with a strain deficient in the protective antigen toxin component enabled to address its role in the diffusion of LF and EF within the host. Our data provide a picture of the in vivo complexity of the infectious process. PMID:26996161

  1. In vivo dynamics of active edema and lethal factors during anthrax.

    PubMed

    Rougeaux, Clémence; Becher, François; Ezan, Eric; Tournier, Jean-Nicolas; Goossens, Pierre L

    2016-01-01

    Lethal and edema toxins are critical virulence factors of Bacillus anthracis. However, little is known about their in vivo dynamics of production during anthrax. In this study, we unraveled for the first time the in vivo kinetics of production of the toxin components EF (edema factor) and LF (lethal factor) during cutaneous infection with a wild-type toxinogenic encapsulated strain in immuno-competent mice. We stratified the asynchronous infection process into defined stages through bioluminescence imaging (BLI), while exploiting sensitive quantitative methods by measuring the enzymatic activity of LF and EF. LF was produced in high amounts, while EF amounts steadily increased during the infectious process. This led to high LF/EF ratios throughout the infection, with variations between 50 to a few thousands. In the bloodstream, the early detection of active LF and EF despite the absence of bacteria suggests that they may exert long distance effects. Infection with a strain deficient in the protective antigen toxin component enabled to address its role in the diffusion of LF and EF within the host. Our data provide a picture of the in vivo complexity of the infectious process. PMID:26996161

  2. Anthrax Edema Factor Toxicity Is Strongly Mediated by the N-end Rule

    PubMed Central

    Leysath, Clinton E.; Phillips, Damilola D.; Crown, Devorah; Fattah, Rasem J.; Moayeri, Mahtab; Leppla, Stephen H.

    2013-01-01

    Anthrax edema factor (EF) is a calmodulin-dependent adenylate cyclase that converts adenosine triphosphate (ATP) into 3’–5’-cyclic adenosine monophosphate (cAMP), contributing to the establishment of Bacillus anthracis infections and the resulting pathophysiology. We show that EF adenylate cyclase toxin activity is strongly mediated by the N-end rule, and thus is dependent on the identity of the N-terminal amino acid. EF variants having different N-terminal residues varied by more than 100-fold in potency in cultured cells and mice. EF variants having unfavorable, destabilizing N-terminal residues showed much greater activity in cells when the E1 ubiquitin ligase was inactivated or when proteasome inhibitors were present. Taken together, these results show that EF is uniquely affected by ubiquitination and/or proteasomal degradation. PMID:24015319

  3. Revisiting the Concept of Targeting Only Bacillus anthracis Toxins as a Treatment for Anthrax.

    PubMed

    Glinert, Itai; Bar-David, Elad; Sittner, Assa; Weiss, Shay; Schlomovitz, Josef; Ben-Shmuel, Amir; Mechaly, Adva; Altboum, Zeev; Kobiler, David; Levy, Haim

    2016-08-01

    Protective antigen (PA)-based vaccines are effective in preventing the development of fatal anthrax disease both in humans and in relevant animal models. The Bacillus anthracis toxins lethal toxin (lethal factor [LF] plus PA) and edema toxin (edema factor [EF] plus PA) are essential for the establishment of the infection, as inactivation of these toxins results in attenuation of the pathogen. Since the toxins reach high toxemia levels at the bacteremic stages of the disease, the CDC's recommendations include combining antibiotic treatment with antitoxin (anti-PA) immunotherapy. We demonstrate here that while treatment with a highly potent neutralizing monoclonal antibody was highly efficient as postexposure prophylaxis treatment, it failed to protect rabbits with any detectable bacteremia (≥10 CFU/ml). In addition, we show that while PA vaccination was effective against a subcutaneous spore challenge, it failed to protect rabbits against systemic challenges (intravenous injection of vegetative bacteria) with the wild-type Vollum strain or a toxin-deficient mutant. To test the possibility that additional proteins, which are secreted by the bacteria under pathogenicity-stimulating conditions in vitro, may contribute to the vaccine's potency, we immunized rabbits with a secreted protein fraction from a toxin-null mutant. The antiserum raised against the secreted fraction reacts with the bacteria in an immunofluorescence assay. Immunization with the secreted protein fraction did not protect the rabbits against a systemic challenge with the fully pathogenic bacteria. Full protection was obtained only by a combined vaccination with PA and the secreted protein fraction. Therefore, these results indicate that an effective antiserum treatment in advanced stages of anthrax must include toxin-neutralizing antibodies in combination with antibodies against bacterial cell targets. PMID:27270276

  4. Identification of the cellular receptor for anthrax toxin

    NASA Astrophysics Data System (ADS)

    Bradley, Kenneth A.; Mogridge, Jeremy; Mourez, Michael; Collier, R. John; Young, John A. T.

    2001-11-01

    The tripartite toxin secreted by Bacillus anthracis, the causative agent of anthrax, helps the bacterium evade the immune system and can kill the host during a systemic infection. Two components of the toxin enzymatically modify substrates within the cytosol of mammalian cells: oedema factor (OF) is an adenylate cyclase that impairs host defences through a variety of mechanisms including inhibiting phagocytosis; lethal factor (LF) is a zinc-dependent protease that cleaves mitogen-activated protein kinase kinase and causes lysis of macrophages. Protective antigen (PA), the third component, binds to a cellular receptor and mediates delivery of the enzymatic components to the cytosol. Here we describe the cloning of the human PA receptor using a genetic complementation approach. The receptor, termed ATR (anthrax toxin receptor), is a type I membrane protein with an extracellular von Willebrand factor A domain that binds directly to PA. In addition, a soluble version of this domain can protect cells from the action of the toxin.

  5. Crystallographic studies of the Anthrax lethal toxin. Annual report

    SciTech Connect

    Frederick, C.A.

    1996-07-01

    The lethal form of Anthrax results from the inhalation of anthrax spores. Death is primarily due to the effects of the lethal toxin (Protective Antigen (PA) + Lethal Factor) from the causative agent, Bacillus anthracis. All the Anthrax vaccines currently in use or under development contain or produce PA, the major antigenic component of anthrax toxin, and there is a clear need for an improved vaccine for human use. In the previous report we described the first atomic resolution structure of PA, revealing that the molecule is composed largely of beta-sheets organized into four domains. This information can be used in the design. of recombinant PA vaccines. In this report we describe additional features of the full-length PA molecule derived from further crystallographic refinement and careful examination of the structure. We compare two crystal forms of PA grown at different pH values and discuss the functional implications. A complete definition of the function of each domain must await the crystal structure of the PA63 heptamer. We have grown crystals of the heptamer under both detergent and detergent-free conditions, and made substantial progress towards the crystal structure. The mechanism of anthrax intoxication in the light of our results is reviewed.

  6. T cell targeting by anthrax toxins: two faces of the same coin.

    PubMed

    Paccani, Silvia Rossi; Baldari, Cosima T

    2011-06-01

    Bacillus anthracis, similar to other bacterial pathogens, has evolved effective immune evasion strategies to prolong its survival in the host, thus ensuring the unchecked spread of the infection. This function is subserved by lethal (LT) and edema (ET) toxins, two exotoxins produced by vegetative anthrax bacilli following germination of the spores. The structure of these toxins and the mechanism of cell intoxication are topics covered by other reviews in this issue. Here we shall discuss how B. anthracis uses LT and ET to suppress the immune defenses of the host, focusing on T lymphocytes, the key players in adaptive immunity. We shall also summarize recent findings showing that, depending on its concentration, ET has the ability not only to suppress T cell activation but also to promote the polarization of CD4(+) T cells to the Th2 and Th17 subsets, highlighting the potential use of this toxin as an immunomodulator. PMID:22069732

  7. Anthrax lethal toxin disrupts the endothelial permeability barrier through blocking p38 signaling.

    PubMed

    Liu, Tiegang; Milia, Erica; Warburton, Rod R; Hill, Nicholas S; Gaestel, Matthias; Kayyali, Usamah S

    2012-04-01

    Exposure to anthrax causes life-threatening disease through the action of the toxin produced by the Bacillus anthracis bacteria. Lethal factor (LF), an anthrax toxin component which causes severe vascular leak and edema, is a protease which specifically degrades MAP kinase kinases (MKK). We have recently shown that p38 MAP kinase activation leading to HSP27 phosphorylation augments the endothelial permeability barrier. We now show that treatment of rat pulmonary microvascular endothelial cells with anthrax lethal toxin (LeTx), which is composed of LF and the protective antigen, increases endothelial barrier permeability and gap formation between endothelial cells through disrupting p38 signaling. LeTx treatment increases MKK3b degradation and in turn decreases p38 activity at baseline as well as after activation of p38 signaling. Consequently, LeTx treatment decreases activation of the p38 substrate kinase, MK2, and the phosphorylation of the latter's substrate, HSP27. LeTx treatment disrupts other signaling pathways leading to suppression of Erk-mediated signaling, but these effects do not correlate with LeTx-induced barrier compromise. Overexpressing phosphomimicking (pm)HSP27, which protects the endothelial permeability barrier against LeTx, blocks LeTx inactivation of p38 and MK2, but it does not block MKK3b degradation or Erk inactivation. Our results suggest that LeTx might cause vascular leak through inactivating p38-MK2-HSP27 signaling and that activating HSP27 phosphorylation specifically restores p38 signaling and blocks anthrax LeTx toxicity. The fact that barrier integrity could be restored by pmHSP27 overexpression without affecting degradation of MKK3b, or inactivation of Erk, suggests a specific and central role for p38-MK2-HSP27 in endothelial barrier permeability regulation. PMID:21618534

  8. Polyvalent Recognition of Biopolymers:The Design of Potent Inhibitors of Anthrax Toxin

    NASA Astrophysics Data System (ADS)

    Kane, Ravi

    2007-03-01

    Polyvalency -- the simultaneous binding of multiple ligands on one entity to multiple receptors on another -- is a phenomenon that is ubiquitous in nature. We are using a biomimetic approach, inspired by polyvalency, to design potent inhibitors of anthrax toxin. Since the major symptoms and death from anthrax are due primarily to the action of anthrax toxin, the toxin is a prime target for therapeutic intervention. We describe the design of potent polyvalent anthrax toxin inhibitors, and will discuss the role of pattern matching in polyvalent recognition. Pattern-matched polyvalent inhibitors can neutralize anthrax toxin in vivo, and may enable the successful treatment of anthrax during the later stages of the disease, when antibiotic treatment is ineffective.

  9. Anthrax Pathogenesis.

    PubMed

    Moayeri, Mahtab; Leppla, Stephen H; Vrentas, Catherine; Pomerantsev, Andrei P; Liu, Shihui

    2015-01-01

    Anthrax is caused by the spore-forming, gram-positive bacterium Bacillus anthracis. The bacterium's major virulence factors are (a) the anthrax toxins and (b) an antiphagocytic polyglutamic capsule. These are encoded by two large plasmids, the former by pXO1 and the latter by pXO2. The expression of both is controlled by the bicarbonate-responsive transcriptional regulator, AtxA. The anthrax toxins are three polypeptides-protective antigen (PA), lethal factor (LF), and edema factor (EF)-that come together in binary combinations to form lethal toxin and edema toxin. PA binds to cellular receptors to translocate LF (a protease) and EF (an adenylate cyclase) into cells. The toxins alter cell signaling pathways in the host to interfere with innate immune responses in early stages of infection and to induce vascular collapse at late stages. This review focuses on the role of anthrax toxins in pathogenesis. Other virulence determinants, as well as vaccines and therapeutics, are briefly discussed. PMID:26195305

  10. Peptide- and proton-driven allosteric clamps catalyze anthrax toxin translocation across membranes

    PubMed Central

    Das, Debasis; Krantz, Bryan A.

    2016-01-01

    Anthrax toxin is an intracellularly acting toxin in which sufficient information is available regarding the structure of its transmembrane channel, allowing for detailed investigation of models of translocation. Anthrax toxin, comprising three proteins—protective antigen (PA), lethal factor (LF), and edema factor—translocates large proteins across membranes. Here we show that the PA translocase channel has a transport function in which its catalytic active sites operate allosterically. We find that the phenylalanine clamp (ϕ-clamp), the known conductance bottleneck in the PA translocase, gates as either a more closed state or a more dilated state. Thermodynamically, the two channel states have >300-fold different binding affinities for an LF-derived peptide. The change in clamp thermodynamics requires distant α-clamp and ϕ-clamp sites. Clamp allostery and translocation are more optimal for LF peptides with uniform stereochemistry, where the least allosteric and least efficiently translocated peptide had a mixed stereochemistry. Overall, the kinetic results are in less agreement with an extended-chain Brownian ratchet model but, instead, are more consistent with an allosteric helix-compression model that is dependent also on substrate peptide coil-to-helix/helix-to-coil cooperativity. PMID:27506790

  11. Peptide- and proton-driven allosteric clamps catalyze anthrax toxin translocation across membranes.

    PubMed

    Das, Debasis; Krantz, Bryan A

    2016-08-23

    Anthrax toxin is an intracellularly acting toxin in which sufficient information is available regarding the structure of its transmembrane channel, allowing for detailed investigation of models of translocation. Anthrax toxin, comprising three proteins-protective antigen (PA), lethal factor (LF), and edema factor-translocates large proteins across membranes. Here we show that the PA translocase channel has a transport function in which its catalytic active sites operate allosterically. We find that the phenylalanine clamp (ϕ-clamp), the known conductance bottleneck in the PA translocase, gates as either a more closed state or a more dilated state. Thermodynamically, the two channel states have >300-fold different binding affinities for an LF-derived peptide. The change in clamp thermodynamics requires distant α-clamp and ϕ-clamp sites. Clamp allostery and translocation are more optimal for LF peptides with uniform stereochemistry, where the least allosteric and least efficiently translocated peptide had a mixed stereochemistry. Overall, the kinetic results are in less agreement with an extended-chain Brownian ratchet model but, instead, are more consistent with an allosteric helix-compression model that is dependent also on substrate peptide coil-to-helix/helix-to-coil cooperativity. PMID:27506790

  12. Anthrax

    MedlinePlus

    Woolsorter's disease; Ragpicker's disease; Cutaneous anthrax; Gastrointestinal anthrax ... Anthrax commonly affects hoofed animals such as sheep, cattle, and goats. Humans who come into contact with ...

  13. Anthrax Toxin-Expressing Bacillus cereus Isolated from an Anthrax-Like Eschar.

    PubMed

    Marston, Chung K; Ibrahim, Hisham; Lee, Philip; Churchwell, George; Gumke, Megan; Stanek, Danielle; Gee, Jay E; Boyer, Anne E; Gallegos-Candela, Maribel; Barr, John R; Li, Han; Boulay, Darbi; Cronin, Li; Quinn, Conrad P; Hoffmaster, Alex R

    2016-01-01

    Bacillus cereus isolates have been described harboring Bacillus anthracis toxin genes, most notably B. cereus G9241, and capable of causing severe and fatal pneumonias. This report describes the characterization of a B. cereus isolate, BcFL2013, associated with a naturally occurring cutaneous lesion resembling an anthrax eschar. Similar to G9241, BcFL2013 is positive for the B. anthracis pXO1 toxin genes, has a multi-locus sequence type of 78, and a pagA sequence type of 9. Whole genome sequencing confirms the similarity to G9241. In addition to the chromosome having an average nucleotide identity of 99.98% when compared to G9241, BcFL2013 harbors three plasmids with varying homology to the G9241 plasmids (pBCXO1, pBC210 and pBFH_1). This is also the first report to include serologic testing of patient specimens associated with this type of B. cereus infection which resulted in the detection of anthrax lethal factor toxemia, a quantifiable serum antibody response to protective antigen (PA), and lethal toxin neutralization activity. PMID:27257909

  14. Anthrax Toxin-Expressing Bacillus cereus Isolated from an Anthrax-Like Eschar

    PubMed Central

    Marston, Chung K.; Ibrahim, Hisham; Lee, Philip; Churchwell, George; Gumke, Megan; Stanek, Danielle; Gee, Jay E.; Boyer, Anne E.; Gallegos-Candela, Maribel; Barr, John R.; Li, Han; Boulay, Darbi; Cronin, Li; Quinn, Conrad P.; Hoffmaster, Alex R.

    2016-01-01

    Bacillus cereus isolates have been described harboring Bacillus anthracis toxin genes, most notably B. cereus G9241, and capable of causing severe and fatal pneumonias. This report describes the characterization of a B. cereus isolate, BcFL2013, associated with a naturally occurring cutaneous lesion resembling an anthrax eschar. Similar to G9241, BcFL2013 is positive for the B. anthracis pXO1 toxin genes, has a multi-locus sequence type of 78, and a pagA sequence type of 9. Whole genome sequencing confirms the similarity to G9241. In addition to the chromosome having an average nucleotide identity of 99.98% when compared to G9241, BcFL2013 harbors three plasmids with varying homology to the G9241 plasmids (pBCXO1, pBC210 and pBFH_1). This is also the first report to include serologic testing of patient specimens associated with this type of B. cereus infection which resulted in the detection of anthrax lethal factor toxemia, a quantifiable serum antibody response to protective antigen (PA), and lethal toxin neutralization activity. PMID:27257909

  15. Bacillus anthracis Edema Toxin Causes Extensive Tissue Lesions and Rapid Lethality in Mice

    PubMed Central

    Firoved, Aaron M.; Miller, Georgina F.; Moayeri, Mahtab; Kakkar, Rahul; Shen, Yuequan; Wiggins, Jason F.; McNally, Elizabeth M.; Tang, Wei-Jen; Leppla, Stephen H.

    2005-01-01

    Bacillus anthracis edema toxin (ET), an adenylyl cyclase, is an important virulence factor that contributes to anthrax disease. The role of ET in anthrax pathogenesis is, however, poorly understood. Previous studies using crude toxin preparations associated ET with subcutaneous edema, and ET-deficient strains of B. anthracis showed a reduction in virulence. We report the first comprehensive study of ET-induced pathology in an animal model. Highly purified ET caused death in BALB/cJ mice at lower doses and more rapidly than previously seen with the other major B. anthracis virulence factor, lethal toxin. Observations of gross pathology showed intestinal intralumenal fluid accumulation followed by focal hemorrhaging of the ileum and adrenal glands. Histopathological analyses of timed tissue harvests revealed lesions in several tissues including adrenal glands, lymphoid organs, bone, bone marrow, gastrointestinal mucosa, heart, and kidneys. Concomitant blood chemistry analyses supported the induction of tissue damage. Several cytokines increased after ET administration, including granulocyte colony-stimulating factor, eotaxin, keratinocyte-derived cytokine, MCP-1/JE, interleukin-6, interleukin-10, and interleukin-1β. Physiological measurements also revealed a concurrent hypotension and bradycardia. These studies detail the extensive pathological lesions caused by ET and suggest that it causes death due to multiorgan failure. PMID:16251415

  16. Anthrax Toxins in Context of Bacillus anthracis Spores and Spore Germination

    PubMed Central

    Cote, Christopher K.; Welkos, Susan L.

    2015-01-01

    The interaction of anthrax toxin or toxin components with B. anthracis spores has been demonstrated. Germinating spores can produce significant amounts of toxin components very soon after the initiation of germination. In this review, we will summarize the work performed that has led to our understanding of toxin and spore interactions and discuss the complexities associated with these interactions. PMID:26287244

  17. Synthesis of potent inhibitors of anthrax toxin based on poly-L-glutamic acid.

    PubMed

    Joshi, Amit; Saraph, Arundhati; Poon, Vincent; Mogridge, Jeremy; Kane, Ravi S

    2006-01-01

    We report the synthesis of biodegradable polyvalent inhibitors of anthrax toxin based on poly-L-glutamic acid (PLGA). These biocompatible polyvalent inhibitors are at least 4 orders of magnitude more potent than the corresponding monovalent peptides in vitro and are comparable in potency to polyacrylamide-based inhibitors of anthrax toxin assembly. We have elucidated the influence of peptide density on inhibitory potency and demonstrated that these inhibitory potencies are limited by kinetics, with even higher activities seen when the inhibitors are preincubated with the heptameric receptor-binding subunit of anthrax toxin prior to exposure to cells. These polyvalent inhibitors are also effective at neutralizing anthrax toxin in vivo and represent attractive leads for designing biocompatible anthrax therapeutics. PMID:16984137

  18. Ion selectivity of the anthrax toxin channel and its effect on protein translocation

    PubMed Central

    Anderson, Damon; Finkelstein, Alan

    2015-01-01

    Anthrax toxin consists of three ∼85-kD proteins: lethal factor (LF), edema factor (EF), and protective antigen (PA). PA63 (the 63-kD, C-terminal portion of PA) forms heptameric channels ((PA63)7) in planar phospholipid bilayer membranes that enable the translocation of LF and EF across the membrane. These mushroom-shaped channels consist of a globular cap domain and a 14-stranded β-barrel stem domain, with six anionic residues lining the interior of the stem to form rings of negative charges. (PA63)7 channels are highly cation selective, and, here, we investigate the effects on both cation selectivity and protein translocation of mutating each of these anionic residues to a serine. We find that although some of these mutations reduce cation selectivity, selectivity alone does not directly predict the rate of protein translocation; local changes in electrostatic forces must be considered as well. PMID:26170174

  19. Recombinant HSA-CMG2 Is a Promising Anthrax Toxin Inhibitor

    PubMed Central

    Li, Liangliang; Guo, Qiang; Liu, Ju; Zhang, Jun; Yin, Ying; Dong, Dayong; Fu, Ling; Xu, Junjie; Chen, Wei

    2016-01-01

    Anthrax toxin is the major virulence factor produced by Bacillus anthracis. Protective antigen (PA) is the key component of the toxin and has been confirmed as the main target for the development of toxin inhibitors. The inhibition of the binding of PA to its receptor, capillary morphogenesis protein-2 (CMG2), can effectively block anthrax intoxication. The recombinant, soluble von Willebrand factor type A (vWA) domain of CMG2 (sCMG2) has demonstrated potency against anthrax toxin. However, the short half-life of sCMG2 in vivo is a disadvantage for its development as a new anthrax drug. In the present study, we report that HSA-CMG2, a protein combining human serum albumin (HSA) and sCMG2, produced in the Pichia pastoris expression system prolonged the half-life of sCMG2 while maintaining PA binding ability. The IC50 of HSA-CMG2 is similar to those of sCMG2 and CMG2-Fc in in vitro toxin neutralization assays, and HSA-CMG2 completely protects rats from lethal doses of anthrax toxin challenge; these same challenge doses exceed sCMG2 at a sub-equivalent dose ratio and overwhelm CMG2-Fc. Our results suggest that HSA-CMG2 is a promising inhibitor of anthrax toxin and may contribute to the development of novel anthrax drugs. PMID:26805881

  20. Recombinant HSA-CMG2 Is a Promising Anthrax Toxin Inhibitor.

    PubMed

    Li, Liangliang; Guo, Qiang; Liu, Ju; Zhang, Jun; Yin, Ying; Dong, Dayong; Fu, Ling; Xu, Junjie; Chen, Wei

    2016-01-01

    Anthrax toxin is the major virulence factor produced by Bacillus anthracis. Protective antigen (PA) is the key component of the toxin and has been confirmed as the main target for the development of toxin inhibitors. The inhibition of the binding of PA to its receptor, capillary morphogenesis protein-2 (CMG2), can effectively block anthrax intoxication. The recombinant, soluble von Willebrand factor type A (vWA) domain of CMG2 (sCMG2) has demonstrated potency against anthrax toxin. However, the short half-life of sCMG2 in vivo is a disadvantage for its development as a new anthrax drug. In the present study, we report that HSA-CMG2, a protein combining human serum albumin (HSA) and sCMG2, produced in the Pichia pastoris expression system prolonged the half-life of sCMG2 while maintaining PA binding ability. The IC50 of HSA-CMG2 is similar to those of sCMG2 and CMG2-Fc in in vitro toxin neutralization assays, and HSA-CMG2 completely protects rats from lethal doses of anthrax toxin challenge; these same challenge doses exceed sCMG2 at a sub-equivalent dose ratio and overwhelm CMG2-Fc. Our results suggest that HSA-CMG2 is a promising inhibitor of anthrax toxin and may contribute to the development of novel anthrax drugs. PMID:26805881

  1. Electrostatic Ratchet in the Protective Antigen Channel Promotes Anthrax Toxin Translocation*

    PubMed Central

    Wynia-Smith, Sarah L.; Brown, Michael J.; Chirichella, Gina; Kemalyan, Gigi; Krantz, Bryan A.

    2012-01-01

    Central to the power-stroke and Brownian-ratchet mechanisms of protein translocation is the process through which nonequilibrium fluctuations are rectified or ratcheted by the molecular motor to transport substrate proteins along a specific axis. We investigated the ratchet mechanism using anthrax toxin as a model. Anthrax toxin is a tripartite toxin comprised of the protective antigen (PA) component, a homooligomeric transmembrane translocase, which translocates two other enzyme components, lethal factor (LF) and edema factor (EF), into the cytosol of the host cell under the proton motive force (PMF). The PA-binding domains of LF and EF (LFN and EFN) possess identical folds and similar solution stabilities; however, EFN translocates ∼10–200-fold slower than LFN, depending on the electrical potential (Δψ) and chemical potential (ΔpH) compositions of the PMF. From an analysis of LFN/EFN chimera proteins, we identified two 10-residue cassettes comprised of charged sequence that were responsible for the impaired translocation kinetics of EFN. These cassettes have nonspecific electrostatic requirements: one surprisingly prefers acidic residues when driven by either a Δψ or a ΔpH; the second requires basic residues only when driven by a Δψ. Through modeling and experiment, we identified a charged surface in the PA channel responsible for charge selectivity. The charged surface latches the substrate and promotes PMF-driven transport. We propose an electrostatic ratchet in the channel, comprised of opposing rings of charged residues, enforces directionality by interacting with charged cassettes in the substrate, thereby generating forces sufficient to drive unfolding. PMID:23115233

  2. Role of the protective antigen octamer in the molecular mechanism of anthrax lethal toxin stabilization in plasma

    PubMed Central

    Kintzer, Alexander F.; Sterling, Harry J.; Tang, Iok I.; Abdul-Gader, Ali; Miles, Andrew J.; Wallace, B. A.; Williams, Evan R.; Krantz, Bryan A.

    2010-01-01

    Anthrax is caused by strains of Bacillus anthracis that produce two key virulence factors, anthrax toxin (Atx) and a poly-γ-D-glutamic acid capsule. Atx is comprised of three-proteins: protective antigen (PA) and two enzymes, lethal factor (LF) and edema factor (EF). To disrupt cell function, these components must assemble into holotoxin complexes, which contain either a ring-shaped homooctameric or homoheptameric PA oligomer bound to multiple copies of either LF and/or EF, producing lethal toxin (LT), edema toxin, or mixtures thereof. Once a host cell endocytoses these complexes, PA converts into a membrane-inserted channel that translocates LF and EF into the cytosol. LT may assemble on host cell surfaces or extracellularly in plasma. We show that under physiological conditions in bovine plasma that LT complexes containing heptameric PA aggregate and inactivate more readily than LT complexes containing octameric PA. LT complexes containing octameric PA possess enhanced stability, channel forming activity, and macrophage cytotoxicity relative to those containing heptameric PA. Under physiological conditions, multiple biophysical probes reveal that heptameric PA can prematurely adopt the channel conformation, but octameric PA complexes remain in their soluble prechannel configuration allowing them to resist aggregation and inactivation. We conclude that PA may form an octameric oligomeric state as a means to produce a more stable and active LT complex that may circulate freely in the blood. PMID:20433851

  3. Atomic structure of anthrax protective antigen pore elucidates toxin translocation.

    PubMed

    Jiang, Jiansen; Pentelute, Bradley L; Collier, R John; Zhou, Z Hong

    2015-05-28

    Anthrax toxin, comprising protective antigen, lethal factor, and oedema factor, is the major virulence factor of Bacillus anthracis, an agent that causes high mortality in humans and animals. Protective antigen forms oligomeric prepores that undergo conversion to membrane-spanning pores by endosomal acidification, and these pores translocate the enzymes lethal factor and oedema factor into the cytosol of target cells. Protective antigen is not only a vaccine component and therapeutic target for anthrax infections but also an excellent model system for understanding the mechanism of protein translocation. On the basis of biochemical and electrophysiological results, researchers have proposed that a phi (Φ)-clamp composed of phenylalanine (Phe)427 residues of protective antigen catalyses protein translocation via a charge-state-dependent Brownian ratchet. Although atomic structures of protective antigen prepores are available, how protective antigen senses low pH, converts to active pore, and translocates lethal factor and oedema factor are not well defined without an atomic model of its pore. Here, by cryo-electron microscopy with direct electron counting, we determine the protective antigen pore structure at 2.9-Å resolution. The structure reveals the long-sought-after catalytic Φ-clamp and the membrane-spanning translocation channel, and supports the Brownian ratchet model for protein translocation. Comparisons of four structures reveal conformational changes in prepore to pore conversion that support a multi-step mechanism by which low pH is sensed and the membrane-spanning channel is formed. PMID:25778700

  4. Anthrax

    MedlinePlus

    ... worried about anthrax germs being grown as a weapon. The issue of laboratory-grown B. anthracis received ... technologically difficult to use anthrax effectively as a weapon on a large scale. Types of Anthrax The ...

  5. Anthrax

    MedlinePlus

    ... rash and rashes clinical tools newsletter | contact Share | Anthrax Information for adults A A A In cutaneous ... Scientists studying B. anthracis Signs and Symptoms Cutaneous Anthrax Characteristic rash* *The characteristic rash of anthrax looks ...

  6. Peptide Probes Reveal a Hydrophobic Steric Ratchet in the Anthrax Toxin Protective Antigen Translocase.

    PubMed

    Colby, Jennifer M; Krantz, Bryan A

    2015-11-01

    Anthrax toxin is a tripartite virulence factor produced by Bacillus anthracis during infection. Under acidic endosomal pH conditions, the toxin's protective antigen (PA) component forms a transmembrane channel in host cells. The PA channel then translocates its two enzyme components, lethal factor and edema factor, into the host cytosol under the proton motive force. Protein translocation under a proton motive force is catalyzed by a series of nonspecific polypeptide binding sites, called clamps. A 10-residue guest/host peptide model system, KKKKKXXSXX, was used to functionally probe polypeptide-clamp interactions within wild-type PA channels. The guest residues were Thr, Ala, Leu, Phe, Tyr, and Trp. In steady-state translocation experiments, the channel blocked most tightly with peptides that had increasing amounts of nonpolar surface area. Cooperative peptide binding was observed in the Trp-containing peptide sequence but not the other tested sequences. Trp substitutions into a flexible, uncharged linker between the lethal factor amino-terminal domain and diphtheria toxin A chain expedited translocation. Therefore, peptide-clamp sites in translocase channels can sense large steric features (like tryptophan) in peptides, and while these steric interactions may make a peptide translocate poorly, in the context of folded domains, they can make the protein translocate more rapidly presumably via a hydrophobic steric ratchet mechanism. PMID:26363343

  7. The medicinal chemistry of botulinum, ricin and anthrax toxins.

    PubMed

    Hicks, Rickey P; Hartell, Mark G; Nichols, Daniel A; Bhattacharjee, Apurba K; van Hamont, John E; Skillman, Donald R

    2005-01-01

    The potential use of weapons of mass destruction (nuclear, biological or chemical) by terrorist organizations represents a major threat to world peace and safety. Only a limited number of vaccines are available to protect the general population from the medical consequences of these weapons. In addition there are major health concerns associated with a pre-exposure mass vaccination of the general population. To reduce or eliminate the impact of these terrible threats, new drugs must be developed to safely treat individuals exposed to these agents. A review of all therapeutic agents under development for the treatment of the illnesses and injuries that result from exposure to nuclear, biological or chemical warfare agents is beyond the scope of any single article. The intent here is to provide a focused review for medicinal and organic chemists of three widely discussed and easily deployed biological warfare agents, botulinum neurotoxin and ricin toxins and the bacteria Bacillus anthracis. Anthrax will be addressed because of its similarity in both structure and mechanism of catalytic activity with botulinum toxin. The common feature of these three agents is that they exhibit their biological activity via toxin enzymatic hydrolysis of a specific bond in their respective substrate molecules. A brief introduction to the history of each of the biological warfare agents is presented followed by a discussion on the mechanisms of action of each at the molecular level, and a review of current potential inhibitors under investigation. PMID:15790305

  8. A novel mechanism for antibody-based anthrax toxin neutralization: inhibition of prepore-to-pore conversion.

    PubMed

    Mechaly, Adva; Levy, Haim; Epstein, Eyal; Rosenfeld, Ronit; Marcus, Hadar; Ben-Arie, Einat; Shafferman, Avigdor; Ordentlich, Arie; Mazor, Ohad

    2012-09-21

    Protective antigen (PA), a key component of anthrax toxin, mediates the entry of lethal factor (LF) or edema factor (EF) through a membranal pore into target cells. We have previously reported the isolation and chimerization of cAb29, an anti-PA monoclonal antibody that effectively neutralizes anthrax toxin in an unknown mechanism. The aim of this study was to elucidate the neutralizing mechanism of this antibody in vitro and to test its ability to confer post-exposure protection against anthrax in vivo. By systematic evaluation of the steps taking place during the PA-based intoxication process, we found that cAb29 did not interfere with the initial steps of intoxication, namely its ability to bind to the anthrax receptor, the consecutive proteolytic cleavage to PA(63), oligomerization, prepore formation, or LF binding. However, the binding of cAb29 to the prepore prevented its pH-triggered transition to the transmembranal pore, thus preventing the last step of intoxication, i.e. the translocation of LF/EF into the cell. Epitope mapping, using a phage display peptide library, revealed that cAb29 binds the 2α(1) loop in domain 2 of PA, a loop that undergoes major conformational changes during pore formation. In vivo, we found that 100% of anthrax-infected rabbits survived when treated with cAb29 12 h after exposure. In conclusion, these experiments demonstrate that cAb29 exerts its potent neutralizing activity in a unique manner by blocking the prepore-to-pore conversion process. PMID:22869370

  9. The Protective Antigen Component of Anthrax Toxin Forms Functional Octameric Complexes

    PubMed Central

    Kintzer, Alexander F.; Thoren, Katie L.; Sterling, Harry J.; Dong, Ken C.; Feld, Geoffrey K.; Tang, Iok I.; Zhang, Teri T.; Williams, Evan R.; Berger, James M.; Krantz, Bryan A.

    2009-01-01

    The assembly of bacterial toxins and virulence factors is critical to their function, but the regulation of assembly during infection has not been studied. We begin to address this question using anthrax toxin as a model. The protective antigen (PA) component of the toxin assembles into ring-shaped homooligomers that bind the two other enzyme components of the toxin, lethal factor (LF) and edema factor (EF), to form toxic complexes. To disrupt the host, these toxic complexes are endocytosed, such that the PA oligomer forms a membrane-spanning channel that LF and EF translocate through to enter the cytosol. We show using single-channel electrophysiology that PA channels contain two populations of conductance states, which correspond with two different PA pre-channel oligomers observed by electron microscopy—the well-described heptamer and a novel octamer. Mass spectrometry demonstrates that the PA octamer binds four LFs, and assembly routes leading to the octamer are populated with even-numbered, dimeric and tetrameric, PA intermediates. Both heptameric and octameric PA complexes can translocate LF and EF with similar rates and efficiencies. Here we also report a 3.2-Å crystal structure of the PA octamer. The octamer comprises ∼20−30% of the oligomers on cells, but outside of the cell, the octamer is more stable than the heptamer under physiological pH. Thus the PA octamer is a physiological, stable, and active assembly state capable of forming lethal toxins that may withstand the hostile conditions encountered in the bloodstream. This assembly mechanism may provide a novel means to control cytotoxicity. PMID:19627991

  10. Comparative toxicity and efficacy of engineered anthrax lethal toxin variants with broad anti-tumor activities

    SciTech Connect

    Peters, Diane E.; Hoover, Benjamin; Cloud, Loretta Grey; Liu, Shihui; Molinolo, Alfredo A.; Leppla, Stephen H.; Bugge, Thomas H.

    2014-09-01

    We have previously designed and characterized versions of anthrax lethal toxin that are selectively cytotoxic in the tumor microenvironment and which display broad and potent anti-tumor activities in vivo. Here, we have performed the first direct comparison of the safety and efficacy of three engineered anthrax lethal toxin variants requiring activation by either matrix-metalloproteinases (MMPs), urokinase plasminogen activator (uPA) or co-localized MMP/uPA activities. C57BL/6J mice were challenged with six doses of engineered toxins via intraperitoneal (I.P.) or intravenous (I.V.) dose routes to determine the maximum tolerated dose for six administrations (MTD6) and dose-limiting toxicities. Efficacy was evaluated using the B16-BL6 syngraft model of melanoma; mice bearing established tumors were treated with six I.P. doses of toxin and tumor measurements and immunohistochemistry, paired with terminal blood work, were used to elaborate upon the anti-tumor mechanism and relative efficacy of each variant. We found that MMP-, uPA- and dual MMP/uPA-activated anthrax lethal toxins exhibited the same dose-limiting toxicity; dose-dependent GI toxicity. In terms of efficacy, all three toxins significantly reduced primary B16-BL6 tumor burden, ranging from 32% to 87% reduction, and they also delayed disease progression as evidenced by dose-dependent normalization of blood work values. While target organ toxicity and effective doses were similar amongst the variants, the dual MMP/uPA-activated anthrax lethal toxin exhibited the highest I.P. MTD6 and was 1.5–3-fold better tolerated than the single MMP- and uPA-activated toxins. Overall, we demonstrate that this dual MMP/uPA-activated anthrax lethal toxin can be administered safely and is highly effective in a preclinical model of melanoma. This modified bacterial cytotoxin is thus a promising candidate for further clinical development and evaluation for use in treating human cancers. - Highlights: • Toxicity and anti

  11. Anthrax vaccine design: strategies to achieve comprehensive protection against spore, bacillus, and toxin

    PubMed Central

    Wang, Julia Y; Roehrl, Michael H

    2005-01-01

    The successful use of Bacillus anthracis as a lethal biological weapon has prompted renewed research interest in the development of more effective vaccines against anthrax. The disease consists of three critical components: spore, bacillus, and toxin, elimination of any of which confers at least partial protection against anthrax. Current remedies rely on postexposure antibiotics to eliminate bacilli and pre- and postexposure vaccination to target primarily toxins. Vaccines effective against toxin have been licensed for human use, but need improvement. Vaccines against bacilli have recently been developed by us and others. Whether effective vaccines will be developed against spores is still an open question. An ideal vaccine would confer simultaneous protection against spores, bacilli, and toxins. One step towards this goal is our dually active vaccine, designed to destroy both bacilli and toxin. Existing and potential strategies towards potent and effective anthrax vaccines are discussed in this review. PMID:15790405

  12. Dominant-Negative Mutants of a Toxin Subunit: An Approach to Therapy of Anthrax

    NASA Astrophysics Data System (ADS)

    Sellman, Bret R.; Mourez, Michael; John Collier, R.

    2001-04-01

    The protective antigen moiety of anthrax toxin translocates the toxin's enzymic moieties to the cytosol of mammalian cells by a mechanism that depends on its ability to heptamerize and insert into membranes. We identified dominant-negative mutants of protective antigen that co-assemble with the wild-type protein and block its ability to translocate the enzymic moieties across membranes. These mutants strongly inhibited toxin action in cell culture and in an animal intoxication model, suggesting that they could be useful in therapy of anthrax.

  13. Anthrax

    MedlinePlus

    Anthrax is a disease caused by Bacillus anthracis, a germ that lives in soil. Many people know ... bioterror attacks. In the attacks, someone purposely spread anthrax through the U.S. mail. This killed five people ...

  14. Anthrax

    MedlinePlus

    ... made 22 sick. Anthrax is rare. It affects animals such as cattle, sheep, and goats more often than people. People can get anthrax from contact with infected animals, wool, meat, or hides. It can cause three ...

  15. Proton-coupled protein transport through the anthrax toxin channel

    PubMed Central

    Finkelstein, Alan

    2008-01-01

    Anthrax toxin consists of three proteins (approx. 90 kDa each): lethal factor (LF); oedema factor (OF); and protective antigen (PA). The former two are enzymes that act when they reach the cytosol of a targeted cell. To enter the cytosol, however, which they do after being endocytosed into an acidic vesicle compartment, they require the third component, PA. PA (or rather its proteolytically generated fragment PA63) forms at low pH a heptameric β-barrel channel, (PA63)7, through which LF and OF are transported—a phenomenon we have demonstrated in planar phospholipid bilayers. It might appear that (PA63)7 simply forms a large hole through which LF and OF diffuse. However, LF and OF are folded proteins, much too large to fit through the approximately 15 Å diameter (PA63)7 β-barrel. This paper discusses how the (PA63)7 channel both participates in the unfolding of LF and OF and functions in their translocation as a proton–protein symporter. PMID:18957378

  16. Analysis of defined combinations of monoclonal antibodies in anthrax toxin neutralization assays and their synergistic action.

    PubMed

    Ngundi, Miriam M; Meade, Bruce D; Little, Stephen F; Quinn, Conrad P; Corbett, Cindi R; Brady, Rebecca A; Burns, Drusilla L

    2012-05-01

    Antibodies against the protective antigen (PA) component of anthrax toxin play an important role in protection against disease caused by Bacillus anthracis. In this study, we examined defined combinations of PA-specific monoclonal antibodies for their ability to neutralize anthrax toxin in cell culture assays. We observed additive, synergistic, and antagonistic effects of the antibodies depending on the specific antibody combination examined and the specific assay used. Synergistic toxin-neutralizing antibody interactions were examined in more detail. We found that one mechanism that can lead to antibody synergy is the bridging of PA monomers by one antibody, with resultant bivalent binding of the second antibody. These results may aid in optimal design of new vaccines and antibody therapies against anthrax. PMID:22441391

  17. Anthrax.

    PubMed

    Datta, K K; Singh, Jagvir

    2002-01-01

    Anthrax is caused by Bacillus anthracis, an encapulated and spore-forming bacillus. The disease is usually contracted through uptake of spores that remain viable in the contaminated soil for many years. Anthrax is primarily a disease of herbivorous animals and is uncommon in humans who may get the infection through contact with contaminated animals or their products. Anthrax spores germinate after entering the body through skin abrasions (cutaneous anthrax) or by inhalation (inhalation anthrax) or ingestion (gastrointestinal anthrax) and multiply to produce two exotoxins which determine the virulence along with capsule. Although most cases occur within 48 hours of exposure, germination of spores may occur upto 60 days later. While inhalation anthrax is almost always fatal, intestinal anthrax results in death in 25% to 60% of cases. Upto 20% of cases having cutaneous anthrax may die. Antibiotics are effective if the disease is recognised early and treated appropriately. Penicillin is the drug of choice when disease occurs in natural setting. Ciprofloxacin is recommended when aerosols of anthrax spores are used as bioweapon, prophylactic antibiotics should not be prescribed until risk of exposure is considered real by experts. PMID:11876121

  18. ANTXR-1 and -2 independent modulation of a cytotoxicity mediated by anthrax toxin in human cells.

    PubMed

    Fujikura, Daisuke; Toyomane, Kochi; Kamiya, Kozue; Mutoh, Memi; Mifune, Etsuko; Ohnuma, Miyuki; Higashi, Hideaki

    2016-09-01

    Several animal models have shown that anthrax toxin (ATX) elicits a cytotoxic effect on host cells through anthrax toxin receptor (ANTXR) function. In this study, compared with mouse cells, cells obtained from humans exhibited low sensitivity to ATX-mediated cytotoxicity, and the sensitivity was not correlated with expression levels of ANTXRs. ATX treatment also induced a cytotoxic effect in other cultured human cells, human embryonic kidney (HEK) 293 cells, that express ANTXRs at undetectable levels. Furthermore, ectopic expression of ANTXRs in HEK293 cells did not affect the sensitivity to ATX treatment. These findings suggest that there is an ANTXR-independent cytotoxic mechanism in human cells. PMID:27170489

  19. Anthrax toxin lethal factor domain 3 is highly mobile and responsive to ligand binding

    PubMed Central

    Maize, Kimberly M.; Kurbanov, Elbek K.; De La Mora-Rey, Teresa; Geders, Todd W.; Hwang, Dong-Jin; Walters, Michael A.; Johnson, Rodney L.; Amin, Elizabeth A.; Finzel, Barry C.

    2014-01-01

    The secreted anthrax toxin consists of three components: the protective antigen (PA), edema factor (EF) and lethal factor (LF). LF, a zinc metalloproteinase, compromises the host immune system primarily by targeting mitogen-activated protein kinase kinases in macrophages. Peptide substrates and small-molecule inhibitors bind LF in the space between domains 3 and 4 of the hydrolase. Domain 3 is attached on a hinge to domain 2 via residues Ile300 and Pro385, and can move through an angular arc of greater than 35° in response to the binding of different ligands. Here, multiple LF structures including five new complexes with co-crystallized inhibitors are compared and three frequently populated LF conformational states termed ‘bioactive’, ‘open’ and ‘tight’ are identified. The bioactive position is observed with large substrate peptides and leaves all peptide-recognition subsites open and accessible. The tight state is seen in unliganded and small-molecule complex structures. In this state, domain 3 is clamped over certain substrate subsites, blocking access. The open position appears to be an intermediate state between these extremes and is observed owing to steric constraints imposed by specific bound ligands. The tight conformation may be the lowest-energy conformation among the reported structures, as it is the position observed with no bound ligand, while the open and bioactive conformations are likely to be ligand-induced. PMID:25372673

  20. Ion Conductance of the Stem of the Anthrax Toxin Channel during Lethal Factor Translocation

    PubMed Central

    Schiffmiller, Aviva; Finkelstein, Alan

    2014-01-01

    The tripartite anthrax toxin consists of protective antigen (PA), lethal factor (LF), and edema factor (EF). PA63 (the 63 kDa, C-terminal part of PA) forms heptameric channels in cell membranes that allow for the transport of LF and EF into the cytosol. These channels are mushroom-shaped, with a ring of seven phenylalanine residues (known as the phenylalanine clamp) lining the junction between the cap and stem. It is known that when LF is translocated through the channel, the phenylalanine clamp creates a seal that causes an essentially complete block of conduction. In order to examine ion conductance in the stem of the channel, we used Venus yellow fluorescent protein (YFP) as a molecular stopper to trap LFN (the 30 kDa, 263-residue N-terminal segment of LF), and various truncated constructs of LFN, in mutant channels in which the phenylalanine clamp residues were mutated to alanines. Here we present evidence that ion movement occurs within the channel stem (but is stopped, of course, at the phenylalanine clamp) during protein translocation. Furthermore, we also propose that the lower region of the stem plays an important role in securing peptide chains during translocation. PMID:24996036

  1. New Developments in Vaccines, Inhibitors of Anthrax Toxins, and Antibiotic Therapeutics for Bacillus anthracis

    PubMed Central

    Beierlein, J.M.; Anderson, A.C.

    2013-01-01

    Bacillus anthracis, the causative agent responsible for anthrax infections, poses a significant biodefense threat. There is a high mortality rate associated with untreated anthrax infections; specifically, inhalation anthrax is a particularly virulent form of infection with mortality rates close to 100%, even with aggressive treatment. Currently, a vaccine is not available to the general public and few antibiotics have been approved by the FDA for the treatment of inhalation anthrax. With the threat of natural or engineered bacterial resistance to antibiotics and the limited population for whom the current drugs are approved, there is a clear need for more effective treatments against this deadly infection. A comprehensive review of current research in drug discovery is presented in this article, including efforts to improve the purity and stability of vaccines, design inhibitors targeting the anthrax toxins, and identify inhibitors of novel enzyme targets. High resolution structural information for the anthrax toxins and several essential metabolic enzymes has played a significant role in aiding the structure-based design of potent and selective antibiotics. PMID:22050756

  2. Calcium-independent metal-ion catalytic mechanism of anthrax edema factor

    SciTech Connect

    Shen, Yuequan; Zhukovskaya, Natalia L.; Guo, Qing; Florián, Jan; Tang, Wei-Jen

    2009-11-18

    Edema factor (EF), a key anthrax exotoxin, has an anthrax protective antigen-binding domain (PABD) and a calmodulin (CaM)-activated adenylyl cyclase domain. Here, we report the crystal structures of CaM-bound EF, revealing the architecture of EF PABD. CaM has N- and C-terminal domains and each domain can bind two calcium ions. Calcium binding induces the conformational change of CaM from closed to open. Structures of the EF-CaM complex show how EF locks the N-terminal domain of CaM into a closed conformation regardless of its calcium-loading state. This represents a mechanism of how CaM effector alters the calcium affinity of CaM and uncouples the conformational change of CaM from calcium loading. Furthermore, structures of EF-CaM complexed with nucleotides show that EF uses two-metal-ion catalysis, a prevalent mechanism in DNA and RNA polymerases. A histidine (H351) further facilitates the catalysis of EF by activating a water to deprotonate 3'OH of ATP. Mammalian adenylyl cyclases share no structural similarity with EF and they also use two-metal-ion catalysis, suggesting the catalytic mechanism-driven convergent evolution of two structurally diverse adenylyl cyclases.

  3. Molecular determinants for a cardiovascular collapse in anthrax

    PubMed Central

    Brojatsch, Jurgen; Casadevall, Arturo; Goldman, David L.

    2015-01-01

    Bacillus anthracis releases two bipartite proteins, lethal toxin and edema factor, that contribute significantly to the progression of anthrax-associated shock. As blocking the anthrax toxins prevents disease, the toxins are considered the main virulence factors of the bacterium. The anthrax bacterium and the anthrax toxins trigger multiorgan failure associated with enhanced vascular permeability, hemorrhage and cardiac dysfunction in animal challenge models. A recent study using mice that either lacked the anthrax toxin receptor in specific cells and corresponding mice expressing the receptor in specific cell types demonstrated that cardiovascular cells are critical for disease mediated by anthrax lethal toxin. These studies are consistent with involvement of the cardiovascular system, and with an increase of cardiac failure markers observed in human anthrax and in animal models using B. anthracis and anthrax toxins. This review discusses the current state of knowledge regarding the pathophysiology of anthrax and tries to provide a mechanistic model and molecular determinants for the circulatory shock in anthrax. PMID:24389148

  4. Molecular determinants for a cardiovascular collapse in anthrax.

    PubMed

    Brojatsch, Jurgen; Casadevall, Arturo; Goldman, David L

    2014-01-01

    Bacillus anthracis releases two bipartite proteins, lethal toxin and edema factor, that contribute significantly to the progression of anthrax-associated shock. As blocking the anthrax toxins prevents disease, the toxins are considered the main virulence factors of the bacterium. The anthrax bacterium and the anthrax toxins trigger multi-organ failure associated with enhanced vascular permeability, hemorrhage and cardiac dysfunction in animal challenge models. A recent study using mice that either lacked the anthrax toxin receptor in specific cells and corresponding mice expressing the receptor in specific cell types demonstrated that cardiovascular cells are critical for disease mediated by anthrax lethal toxin. These studies are consistent with involvement of the cardiovascular system, and with an increase of cardiac failure markers observed in human anthrax and in animal models using B. anthracis and anthrax toxins. This review discusses the current state of knowledge regarding the pathophysiology of anthrax and tries to provide a mechanistic model and molecular determinants for the circulatory shock in anthrax. PMID:24389148

  5. A heterodimer of a VHH (variable domains of camelid heavy chain-only) antibody that inhibits anthrax toxin cell binding linked to a VHH antibody that blocks oligomer formation is highly protective in an anthrax spore challenge model.

    PubMed

    Moayeri, Mahtab; Leysath, Clinton E; Tremblay, Jacqueline M; Vrentas, Catherine; Crown, Devorah; Leppla, Stephen H; Shoemaker, Charles B

    2015-03-01

    Anthrax disease is caused by a toxin consisting of protective antigen (PA), lethal factor, and edema factor. Antibodies against PA have been shown to be protective against the disease. Variable domains of camelid heavy chain-only antibodies (VHHs) with affinity for PA were obtained from immunized alpacas and screened for anthrax neutralizing activity in macrophage toxicity assays. Two classes of neutralizing VHHs were identified recognizing distinct, non-overlapping epitopes. One class recognizes domain 4 of PA at a well characterized neutralizing site through which PA binds to its cellular receptor. A second neutralizing VHH (JKH-C7) recognizes a novel epitope. This antibody inhibits conversion of the PA oligomer from "pre-pore" to its SDS and heat-resistant "pore" conformation while not preventing cleavage of full-length 83-kDa PA (PA83) by cell surface proteases to its oligomer-competent 63-kDa form (PA63). The antibody prevents endocytosis of the cell surface-generated PA63 subunit but not preformed PA63 oligomers formed in solution. JKH-C7 and the receptor-blocking VHH class (JIK-B8) were expressed as a heterodimeric VHH-based neutralizing agent (VNA2-PA). This VNA displayed improved neutralizing potency in cell assays and protected mice from anthrax toxin challenge with much better efficacy than the separate component VHHs. The VNA protected virtually all mice when separately administered at a 1:1 ratio to toxin and protected mice against Bacillus anthracis spore infection. Thus, our studies show the potential of VNAs as anthrax therapeutics. Due to their simple and stable nature, VNAs should be amenable to genetic delivery or administration via respiratory routes. PMID:25564615

  6. A Heterodimer of a VHH (Variable Domains of Camelid Heavy Chain-only) Antibody That Inhibits Anthrax Toxin Cell Binding Linked to a VHH Antibody That Blocks Oligomer Formation Is Highly Protective in an Anthrax Spore Challenge Model*

    PubMed Central

    Moayeri, Mahtab; Leysath, Clinton E.; Tremblay, Jacqueline M.; Vrentas, Catherine; Crown, Devorah; Leppla, Stephen H.; Shoemaker, Charles B.

    2015-01-01

    Anthrax disease is caused by a toxin consisting of protective antigen (PA), lethal factor, and edema factor. Antibodies against PA have been shown to be protective against the disease. Variable domains of camelid heavy chain-only antibodies (VHHs) with affinity for PA were obtained from immunized alpacas and screened for anthrax neutralizing activity in macrophage toxicity assays. Two classes of neutralizing VHHs were identified recognizing distinct, non-overlapping epitopes. One class recognizes domain 4 of PA at a well characterized neutralizing site through which PA binds to its cellular receptor. A second neutralizing VHH (JKH-C7) recognizes a novel epitope. This antibody inhibits conversion of the PA oligomer from “pre-pore” to its SDS and heat-resistant “pore” conformation while not preventing cleavage of full-length 83-kDa PA (PA83) by cell surface proteases to its oligomer-competent 63-kDa form (PA63). The antibody prevents endocytosis of the cell surface-generated PA63 subunit but not preformed PA63 oligomers formed in solution. JKH-C7 and the receptor-blocking VHH class (JIK-B8) were expressed as a heterodimeric VHH-based neutralizing agent (VNA2-PA). This VNA displayed improved neutralizing potency in cell assays and protected mice from anthrax toxin challenge with much better efficacy than the separate component VHHs. The VNA protected virtually all mice when separately administered at a 1:1 ratio to toxin and protected mice against Bacillus anthracis spore infection. Thus, our studies show the potential of VNAs as anthrax therapeutics. Due to their simple and stable nature, VNAs should be amenable to genetic delivery or administration via respiratory routes. PMID:25564615

  7. Anthrax

    MedlinePlus

    ... that may be prescribed include penicillin, doxycycline, and ciprofloxacin. Inhalation anthrax is treated with a combination of antibiotics such as ciprofloxacin plus another medicine. They are given by IV ( ...

  8. The Design of Potent Liposome-Based Inhibitors of Anthrax Toxin

    NASA Astrophysics Data System (ADS)

    Rai, Prakash; Padala, Chakradhar; Poon, Vincent; Saraph, Arundhati; Basha, Saleem; Kate, Sandesh; Tao, Kevin; Mogridge, Jeremy; Kane, Ravi

    2006-03-01

    Several biological processes involve the recognition of a specific pattern of binding sites on a target surface. Theoreticians have predicted that endowing synthetic biomimetic structures with statistical pattern matching capabilities may impact the development of sensors and separation processes. We demonstrated for the first time that statistical pattern matching significantly enhances the potency of a polyvalent therapeutic -- an anthrax toxin inhibitor. We functionalized liposomes with an inhibitory peptide at different densities and observed a transition in potency at an inter-peptide separation that matches the distance between ligand-binding sites on the heptameric subunit of anthrax toxin. Pattern-matched polyvalent liposomes neutralized anthrax toxin in vitro at concentrations four orders of magnitude lower than the corresponding monovalent peptide. We also showed that polyvalent liposome-based inhibitors can neutralize a microbial toxin in vivo. Statistical pattern matching represents a facile strategy to enhance the potency of therapeutics targeting toxins or pathogens. Our results also illuminate other fundamental aspects of polyvalent recognition --specifically we found that the efficiency of polyvalent inhibition is influenced by the competition between the rates of ligand dissociation and diffusion.

  9. Comparative toxicity and efficacy of engineered anthrax lethal toxin variants with broad anti-tumor activities.

    PubMed

    Peters, Diane E; Hoover, Benjamin; Cloud, Loretta Grey; Liu, Shihui; Molinolo, Alfredo A; Leppla, Stephen H; Bugge, Thomas H

    2014-09-01

    We have previously designed and characterized versions of anthrax lethal toxin that are selectively cytotoxic in the tumor microenvironment and which display broad and potent anti-tumor activities in vivo. Here, we have performed the first direct comparison of the safety and efficacy of three engineered anthrax lethal toxin variants requiring activation by either matrix-metalloproteinases (MMPs), urokinase plasminogen activator (uPA) or co-localized MMP/uPA activities. C57BL/6J mice were challenged with six doses of engineered toxins via intraperitoneal (I.P.) or intravenous (I.V.) dose routes to determine the maximum tolerated dose for six administrations (MTD6) and dose-limiting toxicities. Efficacy was evaluated using the B16-BL6 syngraft model of melanoma; mice bearing established tumors were treated with six I.P. doses of toxin and tumor measurements and immunohistochemistry, paired with terminal blood work, were used to elaborate upon the anti-tumor mechanism and relative efficacy of each variant. We found that MMP-, uPA- and dual MMP/uPA-activated anthrax lethal toxins exhibited the same dose-limiting toxicity; dose-dependent GI toxicity. In terms of efficacy, all three toxins significantly reduced primary B16-BL6 tumor burden, ranging from 32% to 87% reduction, and they also delayed disease progression as evidenced by dose-dependent normalization of blood work values. While target organ toxicity and effective doses were similar amongst the variants, the dual MMP/uPA-activated anthrax lethal toxin exhibited the highest I.P. MTD6 and was 1.5-3-fold better tolerated than the single MMP- and uPA-activated toxins. Overall, we demonstrate that this dual MMP/uPA-activated anthrax lethal toxin can be administered safely and is highly effective in a preclinical model of melanoma. This modified bacterial cytotoxin is thus a promising candidate for further clinical development and evaluation for use in treating human cancers. PMID:24971906

  10. A kinetic analysis of protein transport through the anthrax toxin channel

    PubMed Central

    Kienker, Paul K.; Briggs, Stephen W.; Finkelstein, Alan

    2011-01-01

    Anthrax toxin is composed of three proteins: a translocase heptameric channel, (PA63)7, formed from protective antigen (PA), which allows the other two proteins, lethal factor (LF) and edema factor (EF), to translocate across a host cell’s endosomal membrane, disrupting cellular homeostasis. (PA63)7 incorporated into planar phospholipid bilayer membranes forms a channel capable of transporting LF and EF. Protein translocation through the channel can be driven by voltage on a timescale of seconds. A characteristic of the translocation of LFN, the N-terminal 263 residues of LF, is its S-shaped kinetics. Because all of the translocation experiments reported in the literature have been performed with more than one LFN molecule bound to most of the channels, it is not clear whether the S-shaped kinetics are an intrinsic characteristic of translocation kinetics or are merely a consequence of the translocation in tandem of two or three LFNs. In this paper, we show both in macroscopic and single-channel experiments that even with only one LFN bound to the channel, the translocation kinetics are S shaped. As expected, the translocation rate is slower with more than one LFN bound. We also present a simple electrodiffusion model of translocation in which LFN is represented as a charged rod that moves subject to both Brownian motion and an applied electric field. The cumulative distribution of first-passage times of the rod past the end of the channel displays S-shaped kinetics with a voltage dependence in agreement with experimental data. PMID:21624946

  11. Anthrax Edema Factor: An Ion-Adaptive Mechanism of Catalysis with Increased Transition-State Conformational Flexibility.

    PubMed

    Jara, Gabriel E; Martínez, Leandro

    2016-07-14

    Edema Factor (EF) is one of three major toxins of anthrax. EF is an adenylyl cyclase that disrupts cell signaling by accelerating the conversion of ATP into cyclic-AMP. EF has a much higher catalytic rate than that of mammalian adenylyl cyclases (mACs). Crystal structures were obtained for mACs and EF, but the molecular basis for different catalytic activities remained poorly understood. In particular, the arrangement of the active site in EF is unclear in what concerns the number of ions present and the conformation of the substrate. Here, we use quantum mechanics-molecular mechanics simulations to estimate the free-energy profiles for the reaction catalyzed by EF and a mAC. We found that EF catalysis is possible, and faster than that of mACs, in both one and two Mg(2+)-ion-binding modes, providing adaptive plasticity to host-cell environments. In both enzymes, the reaction mechanisms are highly associative. However, mechanistic differences exist. In the mAC, the nucleophile oxygen (ATP-O3') is consistently coordinated to one of the Mg(2+) ions, increasing its acidity. In EF, on the other hand, this coordination is eventual and not essential for the reaction to proceed. The persistent coordination of O3' to the ion is favored in mACs by a greater ion partial charge. In EF, the reduced acidity of the O3' oxygen is compensated by the presence of the His351 residue for proton abstraction. As proton transfer in EF does not require persistent attachment of the substrate to an ion, the substrate (ATP) and transition state display greater conformational flexibilities. These greater flexibilities allow the sampling of lower-energy conformations and might represent an entropic advantage for catalytic efficiency. PMID:27260163

  12. Edema Toxin Impairs Anthracidal Phospholipase A2 Expression by Alveolar Macrophages

    PubMed Central

    Raymond, Benoit; Leduc, Dominique; Ravaux, Lucas; Goffic, Ronan Le; Candela, Thomas; Raymondjean, Michel; Goossens, Pierre Louis; Touqui, Lhousseine

    2007-01-01

    Bacillus anthracis, the etiological agent of anthrax, is a spore-forming Gram-positive bacterium. Infection with this pathogen results in multisystem dysfunction and death. The pathogenicity of B. anthracis is due to the production of virulence factors, including edema toxin (ET). Recently, we established the protective role of type-IIA secreted phospholipase A2 (sPLA2-IIA) against B. anthracis. A component of innate immunity produced by alveolar macrophages (AMs), sPLA2-IIA is found in human and animal bronchoalveolar lavages at sufficient levels to kill B. anthracis. However, pulmonary anthrax is almost always fatal, suggesting the potential impairment of sPLA2-IIA synthesis and/or action by B. anthracis factors. We investigated the effect of purified ET and ET-deficient B. anthracis strains on sPLA2-IIA expression in primary guinea pig AMs. We report that ET inhibits sPLA2-IIA expression in AMs at the transcriptional level via a cAMP/protein kinase A–dependent process. Moreover, we show that live B. anthracis strains expressing functional ET inhibit sPLA2-IIA expression, whereas ET-deficient strains induced this expression. This stimulatory effect, mediated partly by the cell wall peptidoglycan, can be counterbalanced by ET. We conclude that B. anthracis down-regulates sPLA2-IIA expression in AMs through a process involving ET. Our study, therefore, describes a new molecular mechanism implemented by B. anthracis to escape innate host defense. These pioneering data will provide new molecular targets for future intervention against this deathly pathogen. PMID:18069891

  13. Cryo-electron microscopy study of bacteriophage T4 displaying anthrax toxin proteins

    SciTech Connect

    Fokine, Andrei; Bowman, Valorie D.; Battisti, Anthony J.; Li Qin; Chipman, Paul R.; Rao, Venigalla B.; Rossmann, Michael G.

    2007-10-25

    The bacteriophage T4 capsid contains two accessory surface proteins, the small outer capsid protein (Soc, 870 copies) and the highly antigenic outer capsid protein (Hoc, 155 copies). As these are dispensable for capsid formation, they can be used for displaying proteins and macromolecular complexes on the T4 capsid surface. Anthrax toxin components were attached to the T4 capsid as a fusion protein of the N-terminal domain of the anthrax lethal factor (LFn) with Soc. The LFn-Soc fusion protein was complexed in vitro with Hoc{sup -}Soc{sup -}T4 phage. Subsequently, cleaved anthrax protective antigen heptamers (PA63){sub 7} were attached to the exposed LFn domains. A cryo-electron microscopy study of the decorated T4 particles shows the complex of PA63 heptamers with LFn-Soc on the phage surface. Although the cryo-electron microscopy reconstruction is unable to differentiate on its own between different proposed models of the anthrax toxin, the density is consistent with a model that had predicted the orientation and position of three LFn molecules bound to one PA63 heptamer.

  14. Select human anthrax protective antigen epitope-specific antibodies provide protection from lethal toxin challenge.

    PubMed

    Crowe, Sherry R; Ash, Linda L; Engler, Renata J M; Ballard, Jimmy D; Harley, John B; Farris, A Darise; James, Judith A

    2010-07-15

    Bacillus anthracis remains a serious bioterrorism concern, and the currently licensed vaccine remains an incomplete solution for population protection from inhalation anthrax and has been associated with concerns regarding efficacy and safety. Thus, understanding how to generate long-lasting protective immunity with reduced immunizations or provide protection through postexposure immunotherapeutics are long-sought goals. Through evaluation of a large military cohort, we characterized the levels of antibodies against protective antigen and found that over half of anthrax vaccinees had low serum levels of in vitro toxin neutralization capacity. Using solid-phase epitope mapping and confirmatory assays, we identified several neutralization-associated humoral epitopes and demonstrated that select antipeptide responses mediated protection in vitro. Finally, passively transferred antibodies specific for select epitopes provided protection in an in vivo lethal toxin mouse model. Identification of these antigenic regions has important implications for vaccine design and the development of directed immunotherapeutics. PMID:20533877

  15. Biochip for the Detection of Bacillus anthracis Lethal Factor and Therapeutic Agents against Anthrax Toxins.

    PubMed

    Silin, Vitalii; Kasianowicz, John J; Michelman-Ribeiro, Ariel; Panchal, Rekha G; Bavari, Sina; Robertson, Joseph W F

    2016-01-01

    Tethered lipid bilayer membranes (tBLMs) have been used in many applications, including biosensing and membrane protein structure studies. This report describes a biosensor for anthrax toxins that was fabricated through the self-assembly of a tBLM with B. anthracis protective antigen ion channels that are both the recognition element and electrochemical transducer. We characterize the sensor and its properties with electrochemical impedance spectroscopy and surface plasmon resonance. The sensor shows a sensitivity similar to ELISA and can also be used to rapidly screen for molecules that bind to the toxins and potentially inhibit their lethal effects. PMID:27348008

  16. Combining Anthrax Vaccine and Therapy: a Dominant-Negative Inhibitor of Anthrax Toxin Is Also a Potent and Safe Immunogen for Vaccines

    PubMed Central

    Aulinger, Benedikt A.; Roehrl, Michael H.; Mekalanos, John J.; Collier, R. John; Wang, Julia Y.

    2005-01-01

    Anthrax is caused by the unimpeded growth of Bacillus anthracis in the host and the secretion of toxins. The currently available vaccine is based on protective antigen (PA), a central component of anthrax toxin. Vaccination with PA raises no direct immune response against the bacilli and, being a natural toxin component, PA might be hazardous when used immediately following exposure to B. anthracis. Thus, we have sought to develop a vaccine or therapeutic agent that is safe and eliminates both secreted toxins and bacilli. To that end, we have previously developed a dually active vaccine by conjugating the capsular poly-γ-d-glutamate (PGA) with PA to elicit the production of antibodies specific for both bacilli and toxins. In the present report, we describe the improved potency of anthrax vaccines through the use of a dominant-negative inhibitory (DNI) mutant to replace PA in PA or PA-PGA vaccines. When tested in mice, DNI alone is more immunogenic than PA, and DNI-PGA conjugate elicits significantly higher levels of antibodies against PA and PGA than PA-PGA conjugate. To explain the enhanced immunogenicity of DNI, we propose that the two point mutations in DNI may have improved epitopes of PA allowing better antigen presentation to helper T cells. Alternatively, these mutations may enhance the immunological processing of PA by altering endosomal trafficking of the toxin in antigen-presenting cells. Because DNI has previously been demonstrated to inhibit anthrax toxin, postexposure use of DNI-based vaccines, including conjugate vaccines, may provide improved immunogenicity and therapeutic activity simultaneously. PMID:15908368

  17. Immunization of Mice with Anthrax Protective Antigen Limits Cardiotoxicity but Not Hepatotoxicity Following Lethal Toxin Challenge

    PubMed Central

    Devera, T. Scott; Prusator, Dawn K.; Joshi, Sunil K.; Ballard, Jimmy D.; Lang, Mark L.

    2015-01-01

    Protective immunity against anthrax is inferred from measurement of vaccine antigen-specific neutralizing antibody titers in serum samples. In animal models, in vivo challenges with toxin and/or spores can also be performed. However, neither of these approaches considers toxin-induced damage to specific organ systems. It is therefore important to determine to what extent anthrax vaccines and existing or candidate adjuvants can provide organ-specific protection against intoxication. We therefore compared the ability of Alum, CpG DNA and the CD1d ligand α-galactosylceramide (αGC) to enhance protective antigen-specific antibody titers, to protect mice against challenge with lethal toxin, and to block cardiotoxicity and hepatotoxicity. By measurement of serum cardiac Troponin I (cTnI), and hepatic alanine aminotransferase (ALT), and aspartate aminotransferase (AST), it was apparent that neither vaccine modality prevented hepatic intoxication, despite high Ab titers and ultimate survival of the subject. In contrast, cardiotoxicity was greatly diminished by prior immunization. This shows that a vaccine that confers survival following toxin exposure may still have an associated morbidity. We propose that organ-specific intoxication should be monitored routinely during research into new vaccine modalities. PMID:26120785

  18. Endocytosis of the Anthrax Toxin Is Mediated by Clathrin, Actin and Unconventional Adaptors

    PubMed Central

    Abrami, Laurence; Bischofberger, Mirko; Kunz, Béatrice; Groux, Romain; van der Goot, F. Gisou

    2010-01-01

    The anthrax toxin is a tripartite toxin, where the two enzymatic subunits require the third subunit, the protective antigen (PA), to interact with cells and be escorted to their cytoplasmic targets. PA binds to cells via one of two receptors, TEM8 and CMG2. Interestingly, the toxin times and triggers its own endocytosis, in particular through the heptamerization of PA. Here we show that PA triggers the ubiquitination of its receptors in a β-arrestin-dependent manner and that this step is required for clathrin-mediated endocytosis. In addition, we find that endocytosis is dependent on the heterotetrameric adaptor AP-1 but not the more conventional AP-2. Finally, we show that endocytosis of PA is strongly dependent on actin. Unexpectedly, actin was also found to be essential for efficient heptamerization of PA, but only when bound to one of its 2 receptors, TEM8, due to the active organization of TEM8 into actin-dependent domains. Endocytic pathways are highly modular systems. Here we identify some of the key players that allow efficient heptamerization of PA and subsequent ubiquitin-dependent, clathrin-mediated endocytosis of the anthrax toxin. PMID:20221438

  19. A microfluidic live cell assay to study anthrax toxin induced cell lethality assisted by conditioned medium

    PubMed Central

    Shen, Jie; Cai, Changzu; Yu, Zhilong; Pang, Yuhong; Zhou, Ying; Qian, Lili; Wei, Wensheng; Huang, Yanyi

    2015-01-01

    It is technically challenging to investigate the function of secreted protein in real time by supply of conditioned medium that contains secreted protein of interest. The internalization of anthrax toxin is facilitated by a secreted protein Dickkopf-1 (DKK1) and its receptor, and eventually leads to cell lethality. To monitor the dynamic interplay between these components in live cells, we use an integrated microfluidic device to perform the cell viability assays with real-time controlled culture microenvironment in parallel. Conditioned medium, which contains the secreted proteins from specific cell lines, can be continuously pumped towards the cells that exposed to toxin. The exogenous DKK1 secreted from distant cells is able to rescue the sensitivity to toxin for those DKK1-knocked-down cells. This high-throughput assay allows us to precisely quantify the dynamic interaction between key components that cause cell death, and provide independent evidence of the function of DKK1 in the complex process of anthrax toxin internalization. PMID:25731605

  20. Immunization of Mice with Anthrax Protective Antigen Limits Cardiotoxicity but Not Hepatotoxicity Following Lethal Toxin Challenge.

    PubMed

    Devera, T Scott; Prusator, Dawn K; Joshi, Sunil K; Ballard, Jimmy D; Lang, Mark L

    2015-07-01

    Protective immunity against anthrax is inferred from measurement of vaccine antigen-specific neutralizing antibody titers in serum samples. In animal models, in vivo challenges with toxin and/or spores can also be performed. However, neither of these approaches considers toxin-induced damage to specific organ systems. It is therefore important to determine to what extent anthrax vaccines and existing or candidate adjuvants can provide organ-specific protection against intoxication. We therefore compared the ability of Alum, CpG DNA and the CD1d ligand α-galactosylceramide (αGC) to enhance protective antigen-specific antibody titers, to protect mice against challenge with lethal toxin, and to block cardiotoxicity and hepatotoxicity. By measurement of serum cardiac Troponin I (cTnI), and hepatic alanine aminotransferase (ALT), and aspartate aminotransferase (AST), it was apparent that neither vaccine modality prevented hepatic intoxication, despite high Ab titers and ultimate survival of the subject. In contrast, cardiotoxicity was greatly diminished by prior immunization. This shows that a vaccine that confers survival following toxin exposure may still have an associated morbidity. We propose that organ-specific intoxication should be monitored routinely during research into new vaccine modalities. PMID:26120785

  1. A role for PACE4 in the proteolytic activation of anthrax toxin protective antigen.

    PubMed Central

    Gordon, V M; Rehemtulla, A; Leppla, S H

    1997-01-01

    Several bacterial protein toxins require activation by eukaryotic proteases. Previous studies have shown that anthrax toxin protective antigen (PA), Pseudomonas exotoxin A (PE), and diphtheria toxin (DT) are cleaved by furin C-terminal to the sequences RKKR, RQPR, and RVRR, respectively. Because furin-deficient cells retain some sensitivity to PA and DT, it is evident that other cellular proteases can activate these toxins. Whereas furin has been shown to require arginine residues at positions -1 and -4 for substrate recognition, another protease with an activity which could substitute for furin in toxin activation, the furin-related protease PACE4, requires basic residues in the -1, -2, and -4 positions of the substrate sequence. To examine the relative roles of furin and PACE4 in toxin activation, we used furin-deficient CHO cells (FD11 cells) transfected with either the furin (FD11/furin cells) or PACE4 (FD11/PACE4 cells) gene. Mutant PA proteins containing the cleavage sequence RAAR or KR were cytotoxic toward cells expressing only PACE4. In vitro cleavage data demonstrated that PACE4 can recognize RAAR and, to a much lesser extent, KR and RR. When extracts from PACE4-transfected cells were used as a source of proteases, PACE4 had minimal activity, indicating that it had been partially inactivated or did not remain associated with the cell membranes. Cleavage of iodinated PA containing the sequence RKKR or RAAR was detected on the surface of all cell types tested, but cleavage of a dibasic sequence was detected only intracellularly and only in cells that expressed furin or PACE4. The data provide evidence that PACE4 is present at the exterior of cells, that it plays a role in the proteolytic activation of anthrax toxin PA, and that PACE4 can activate substrates at the sequence RAAR or KR. PMID:9234799

  2. Ultrasensitive detection of protease activity of anthrax and botulinum toxins by a new PCR-based assay.

    PubMed

    Kolesnikov, Alexander V; Kozyr, Arina V; Ryabko, Alyona K; Shemyakin, Igor G

    2016-02-01

    Anthrax and botulism are dangerous infectious diseases that can be fatal unless detected and treated quickly. Fatalities from these diseases are primarily due to endopeptidase toxins secreted by the pathogens. Rapid and sensitive detection of the presence of active toxins is the key element for protection from natural outbreaks of anthrax and botulism, as well as from the threat of bioterrorism. We describe an ultrasensitive polymerase chain reaction (PCR)-based assay for detecting proteolytic activity of anthrax and botulinum toxins using composite probes consisting of covalent peptide-DNA conjugate for the detection of anthrax, and noncovalent protein-aptamer assembly to assay botulinum toxin activity. Probes immobilized on the solid-phase support are cleaved by toxins to release DNA, which is detected by real-time PCR. Both assays can detect subpicogram quantities of active toxins isolated from composite matrices. Special procedures were developed to isolate intact toxins from the matrices under mild conditions. The assay is rapid, uses proven technologies, and can be modified to detect other proteolytic and biopolymer-degrading enzymes. PMID:26620058

  3. Combination of two candidate subunit vaccine antigens elicits protective immunity to ricin and anthrax toxin in mice.

    PubMed

    Vance, David J; Rong, Yinghui; Brey, Robert N; Mantis, Nicholas J

    2015-01-01

    In an effort to develop combination vaccines for biodefense, we evaluated a ricin subunit antigen, RiVax, given in conjunction with an anthrax protective antigen, DNI. The combination led to high endpoint titer antibody response, neutralizing antibodies, and protective immunity against ricin and anthrax lethal toxin. This is a natural combination vaccine, since both antigens are recombinant subunit proteins that would be given to the same target population. PMID:25475957

  4. The Disulfide Bond Cys255-Cys279 in the Immunoglobulin-Like Domain of Anthrax Toxin Receptor 2 Is Required for Membrane Insertion of Anthrax Protective Antigen Pore

    PubMed Central

    Boone, Kyle; Altiyev, Agamyrat; Puschhof, Jens; Sauter, Roland; Arigi, Emma; Ruiz, Blanca; Peng, Xiuli; Almeida, Igor; Sherman, Michael; Xiao, Chuan; Sun, Jianjun

    2015-01-01

    Anthrax toxin receptors act as molecular clamps or switches that control anthrax toxin entry, pH-dependent pore formation, and translocation of enzymatic moieties across the endosomal membranes. We previously reported that reduction of the disulfide bonds in the immunoglobulin-like (Ig) domain of the anthrax toxin receptor 2 (ANTXR2) inhibited the function of the protective antigen (PA) pore. In the present study, the disulfide linkage in the Ig domain was identified as Cys255-Cys279 and Cys230-Cys315. Specific disulfide bond deletion mutants were achieved by replacing Cys residues with Ala residues. Deletion of the disulfide bond C255-C279, but not C230-C315, inhibited the PA pore-induced release of the fluorescence dyes from the liposomes, suggesting that C255-C279 is essential for PA pore function. Furthermore, we found that deletion of C255-C279 did not affect PA prepore-to-pore conversion, but inhibited PA pore membrane insertion by trapping the PA membrane-inserting loops in proteinaceous hydrophobic pockets. Fluorescence spectra of Trp59, a residue adjacent to the PA-binding motif in von Willebrand factor A (VWA) domain of ANTXR2, showed that deletion of C255-C279 resulted in a significant conformational change on the receptor ectodomain. The disulfide deletion-induced conformational change on the VWA domain was further confirmed by single-particle 3D reconstruction of the negatively stained PA-receptor heptameric complexes. Together, the biochemical and structural data obtained in this study provides a mechanistic insight into the role of the receptor disulfide bond C255-C279 in anthrax toxin action. Manipulation of the redox states of the receptor, specifically targeting to C255-C279, may become a novel strategy to treat anthrax. PMID:26107617

  5. Highly predictive support vector machine (SVM) models for anthrax toxin lethal factor (LF) inhibitors.

    PubMed

    Zhang, Xia; Amin, Elizabeth Ambrose

    2016-01-01

    Anthrax is a highly lethal, acute infectious disease caused by the rod-shaped, Gram-positive bacterium Bacillus anthracis. The anthrax toxin lethal factor (LF), a zinc metalloprotease secreted by the bacilli, plays a key role in anthrax pathogenesis and is chiefly responsible for anthrax-related toxemia and host death, partly via inactivation of mitogen-activated protein kinase kinase (MAPKK) enzymes and consequent disruption of key cellular signaling pathways. Antibiotics such as fluoroquinolones are capable of clearing the bacilli but have no effect on LF-mediated toxemia; LF itself therefore remains the preferred target for toxin inactivation. However, currently no LF inhibitor is available on the market as a therapeutic, partly due to the insufficiency of existing LF inhibitor scaffolds in terms of efficacy, selectivity, and toxicity. In the current work, we present novel support vector machine (SVM) models with high prediction accuracy that are designed to rapidly identify potential novel, structurally diverse LF inhibitor chemical matter from compound libraries. These SVM models were trained and validated using 508 compounds with published LF biological activity data and 847 inactive compounds deposited in the Pub Chem BioAssay database. One model, M1, demonstrated particularly favorable selectivity toward highly active compounds by correctly predicting 39 (95.12%) out of 41 nanomolar-level LF inhibitors, 46 (93.88%) out of 49 inactives, and 844 (99.65%) out of 847 Pub Chem inactives in external, unbiased test sets. These models are expected to facilitate the prediction of LF inhibitory activity for existing molecules, as well as identification of novel potential LF inhibitors from large datasets. PMID:26615468

  6. Monitoring the kinetics of the pH-driven transition of the anthrax toxin prepore to the pore by biolayer interferometry and surface plasmon resonance.

    PubMed

    Naik, Subhashchandra; Brock, Susan; Akkaladevi, Narahari; Tally, Jon; McGinn-Straub, Wesley; Zhang, Na; Gao, Phillip; Gogol, E P; Pentelute, B L; Collier, R John; Fisher, Mark T

    2013-09-17

    Domain 2 of the anthrax protective antigen (PA) prepore heptamer unfolds and refolds during endosome acidification to generate an extended 100 Å β barrel pore that inserts into the endosomal membrane. The PA pore facilitates the pH-dependent unfolding and translocation of bound toxin enzymic components, lethal factor (LF) and/or edema factor, from the endosome to the cytoplasm. We constructed immobilized complexes of the prepore with the PA-binding domain of LF (LFN) to monitor the real-time prepore to pore kinetic transition using surface plasmon resonance and biolayer interferometry (BLI). The kinetics of this transition increased as the solution pH was decreased from 7.5 to 5.0, mirroring acidification of the endosome. Once it had undergone the transition, the LFN-PA pore complex was removed from the BLI biosensor tip and deposited onto electron microscopy grids, where PA pore formation was confirmed by negative stain electron microscopy. When the soluble receptor domain (ANTRX2/CMG2) binds the immobilized PA prepore, the transition to the pore state was observed only after the pH was lowered to early (pH 5.5) or late (pH 5.0) endosomal pH conditions. Once the pore formed, the soluble receptor readily dissociated from the PA pore. Separate binding experiments with immobilized PA pores and the soluble receptor indicate that the receptor has a weakened propensity to bind to the transitioned pore. This immobilized anthrax toxin platform can be used to identify or validate potential antimicrobial lead compounds capable of regulating and/or inhibiting anthrax toxin complex formation or pore transitions. PMID:23964683

  7. Identification of a Receptor-Binding Region within Domain 4 of the Protective Antigen Component of Anthrax Toxin

    PubMed Central

    Varughese, Mini; Teixeira, Avelino V.; Liu, Shihui; Leppla, Stephen H.

    1999-01-01

    Anthrax toxin from Bacillus anthracis is a three-component toxin consisting of lethal factor (LF), edema factor (EF), and protective antigen (PA). LF and EF are the catalytic components of the toxin, whereas PA is the receptor-binding component. To identify residues of PA that are involved in interaction with the cellular receptor, two solvent-exposed loops of domain 4 of PA (amino acids [aa] 679 to 693 and 704 to 723) were mutagenized, and the altered proteins purified and tested for toxicity in the presence of LF. In addition to the intended substitutions, novel mutations were introduced by errors that occurred during PCR. Substitutions within the large loop (aa 704 to 723) had no effect on PA activity. A mutated protein, LST-35, with three substitutions in the small loop (aa 679 to 693), bound weakly to the receptor and was nontoxic. A mutated protein, LST-8, with changes in three separate regions did not bind to receptor and was nontoxic. Toxicity was greatly decreased by truncation of the C-terminal 3 to 5 aa, but not by their substitution with nonnative residues or the extension of the terminus with nonnative sequences. Comparison of the 28 mutant proteins described here showed that the large loop (aa 704 to 722) is not involved in receptor binding, whereas residues in and near the small loop (aa 679 to 693) play an important role in receptor interaction. Other regions of domain 4, in particular residues at the extreme C terminus, appear to play a role in stabilizing a conformation needed for receptor-binding activity. PMID:10085028

  8. Role of macrophage oxidative burst in the action of anthrax lethal toxin.

    PubMed Central

    Hanna, P. C.; Kruskal, B. A.; Ezekowitz, R. A.; Bloom, B. R.; Collier, R. J.

    1994-01-01

    BACKGROUND: Major symptoms and death from systemic Bacillus anthracis infections are mediated by the action of the pathogen's lethal toxin on host macrophages. High levels of the toxin are cytolytic to macrophages, whereas low levels stimulate these cells to produce cytokines (interleukin-1 beta and tumor necrosis factor-alpha), which induce systemic shock and death. MATERIALS AND METHODS: Experiments were performed to assess the possibility that the oxidative burst may be involved in one or both of lethal toxin's effects on macrophages. Toximediated cell lysis, superoxide anion and cytokine production were measured. Effects of antioxidants and macrophage mutations were examined. RESULTS: RAW264.7 murine macrophages treated with high levels of toxin released large amounts of superoxide anion, beginning at about 1 hr, which correlates with the onset of cytolysis. Cytolysis could be blocked with various exogenous antioxidants or with N-acetyl-L-cysteine and methionine, which promote production of the endogenous antioxidant, glutathione. Mutant murine macrophage lines deficient in production of reactive oxygen intermediates (ROIs) were relatively insensitive to the lytic effects of the toxin, whereas a line with increased oxidative burst potential showed elevated sensitivity. Also, cultured blood monocyte-derived macrophages from a patient with Chronic Granulomatous Disease, a disorder in which the phagocyte's oxidative burst is disabled, were totally resistant to toxin, in contrast to control monocytes. CONCLUSIONS: These results imply that the cytolytic effect of the toxin is mediated by ROIs. Additionally, cytokine production and consequent pathologies showed partial dependence on macrophage ROIs. Antioxidants moderately inhibited toxin-induced cytokine production in vitro, and BALB/c mice pretreated with N-acetyl-L-cysteine or mepacrine showed partial protection against lethal toxin. Thus ROIs are involved in both the cytolytic action of anthrax lethal toxin and

  9. Diminished but Not Abolished Effect of Two His351 Mutants of Anthrax Edema Factor in a Murine Model

    PubMed Central

    Zhao, Taoran; Zhao, Xinghui; Liu, Ju; Meng, Yingying; Feng, Yingying; Fang, Ting; Zhang, Jinlong; Yang, Xiuxu; Li, Jianmin; Xu, Junjie; Chen, Wei

    2016-01-01

    Edema toxin (ET), which is composed of a potent adenylate cyclase (AC), edema factor (EF), and protective antigen (PA), is one of the major toxicity factors of Bacillus anthracis. In this study, we introduced mutations in full-length EF to generate alanine EF(H351A) and arginine EF(H351R) variants. In vitro activity analysis displayed that the adenylyl cyclase activity of both the mutants was significantly diminished compared with the wild-type EF. When the native and mutant toxins were administered subcutaneously in a mouse footpad edema model, severe acute swelling was evoked by wild-type ET, while the symptoms induced by mutant toxins were very minor. Systemic administration of these EF variants caused non-lethal hepatotoxicity. In addition, EF(H351R) exhibited slightly higher activity in causing more severe edema than EF(H351A). Our findings demonstrate that the toxicity of ET is not abolished by substitution of EF residue His351 by alanine or arginine. These results also indicate the potential of the mouse footpad edema model as a sensitive method for evaluating both ET toxicity and the efficacy of candidate therapeutic agents. PMID:26848687

  10. Diminished but Not Abolished Effect of Two His351 Mutants of Anthrax Edema Factor in a Murine Model.

    PubMed

    Zhao, Taoran; Zhao, Xinghui; Liu, Ju; Meng, Yingying; Feng, Yingying; Fang, Ting; Zhang, Jinlong; Yang, Xiuxu; Li, Jianmin; Xu, Junjie; Chen, Wei

    2016-02-01

    Edema toxin (ET), which is composed of a potent adenylate cyclase (AC), edema factor (EF), and protective antigen (PA), is one of the major toxicity factors of Bacillus anthracis. In this study, we introduced mutations in full-length EF to generate alanine EF(H351A) and arginine EF(H351R) variants. In vitro activity analysis displayed that the adenylyl cyclase activity of both the mutants was significantly diminished compared with the wild-type EF. When the native and mutant toxins were administered subcutaneously in a mouse footpad edema model, severe acute swelling was evoked by wild-type ET, while the symptoms induced by mutant toxins were very minor. Systemic administration of these EF variants caused non-lethal hepatotoxicity. In addition, EF(H351R) exhibited slightly higher activity in causing more severe edema than EF(H351A). Our findings demonstrate that the toxicity of ET is not abolished by substitution of EF residue His351 by alanine or arginine. These results also indicate the potential of the mouse footpad edema model as a sensitive method for evaluating both ET toxicity and the efficacy of candidate therapeutic agents. PMID:26848687

  11. Designed Azolopyridinium Salts Block Protective Antigen Pores In Vitro and Protect Cells from Anthrax Toxin

    PubMed Central

    Duscha, Kerstin; Riedl, Zsuzsanna; Huber-Lang, Markus; Benz, Roland; Hajós, György; Barth, Holger

    2013-01-01

    Background Several intracellular acting bacterial protein toxins of the AB-type, which are known to enter cells by endocytosis, are shown to produce channels. This holds true for protective antigen (PA), the binding component of the tripartite anthrax-toxin of Bacillus anthracis. Evidence has been presented that translocation of the enzymatic components of anthrax-toxin across the endosomal membrane of target cells and channel formation by the heptameric/octameric PA63 binding/translocation component are related phenomena. Chloroquine and some 4-aminoquinolones, known as potent drugs against Plasmodium falciparium infection of humans, block efficiently the PA63-channel in a dose dependent way. Methodology/Principal Findings Here we demonstrate that related positively charged heterocyclic azolopyridinium salts block the PA63-channel in the µM range, when both, inhibitor and PA63 are added to the same side of the membrane, the cis-side, which corresponds to the lumen of acidified endosomal vesicles of target cells. Noise-analysis allowed the study of the kinetics of the plug formation by the heterocycles. In vivo experiments using J774A.1 macrophages demonstrated that the inhibitors of PA63-channel function also efficiently block intoxication of the cells by the combination lethal factor and PA63 in the same concentration range as they block the channels in vitro. Conclusions/Significance These results strongly argue in favor of a transport of lethal factor through the PA63-channel and suggest that the heterocycles used in this study could represent attractive candidates for development of novel therapeutic strategies against anthrax. PMID:23840407

  12. Crystallographic studies of the anthrax lethal toxin. Final report, 1 July 1994-31 December 1996

    SciTech Connect

    Frederick, C.A.

    1997-01-01

    Protective Antigen (PA) is the central component of the three-part protein toxin secreted by Bacillus anthraces, the organism responsible for anthrax. Following proteolytic activation on the host cell surface, PA forms a membrane-inserting heptamer that translocates the toxic enzymes into the cytosol. We have solved the crystal structure of monomeric PA at 2.1 A resolution and the water-soluble heptamer at 4.5 A resolution. The monomer is organized mainly into antiparallel b-sheets and has four domains: an N-terminal domain containing two calcium ions; a heptamerization domain containing a large flexible loop implicated in membrane insertion; a small domain of unknown function; and a C-terminal receptor-binding domain. Removal of a 20 kDa fragment from the N-terminal domain permits assembly of the heptamer, a ring-shaped structure with a negatively charged lumen, and exposes a large hydrophobic surface for binding the toxic enzymes. We present a model of pH-dependent membrane insertion involving formation of a porin-like membrane-spanning b barrel. These studies greatly enhance current understanding of the mechanism of anthrax intoxication, and will be useful in the design of recombinant anthrax vaccines.

  13. [Bacillus anthracis: causative agent of anthrax].

    PubMed

    Boutiba-Ben Boubaker, I; Ben Redjeb, S

    2001-12-01

    Anthrax, an acute infectious disease of historical importance, is once again regaining interest with its use as a biological weapon. It is caused by B. anthracis, a Gram positive spore forming rod usually surrounded by a capsule and producing toxin. It occurs most frequently as an epizootic or enzootic disease of herbivores that acquire spores form direct contact with contaminated soil. Spores can survive for many years in soil. Animal vaccination programs have reduced drastically the disease in developed countries. In humans, the disease is acquired following contact with anthrax infected animals or their products. 3 types of anthrax infection can occur: cutaneous, inhalational and gastro intestinal. Cutaneous anthrax is the most common observed form. When germination occurs, replicating bacteria release toxin leading to hemorrhage, edema, necrosis and death. Full virulence of B. anthracis requires the presence of both antiphagocytic capsule and 3 toxin components (protective antigen, lethal factor and edema factor). Most naturally occurring anthrax strains are sensitive to penicillin but resistant to third generation cephalosporins. Post exposure prophylaxis is indicated to prevent inhalational anthrax. PMID:11892436

  14. Engineering Anthrax Toxin Variants That Exclusively Form Octamers and Their Application to Targeting Tumors*

    PubMed Central

    Phillips, Damilola D.; Fattah, Rasem J.; Crown, Devorah; Zhang, Yi; Liu, Shihui; Moayeri, Mahtab; Fischer, Elizabeth R.; Hansen, Bryan T.; Ghirlando, Rodolfo; Nestorovich, Ekaterina M.; Wein, Alexander N.; Simons, Lacy; Leppla, Stephen H.; Leysath, Clinton E.

    2013-01-01

    Anthrax toxin protective antigen (PA) delivers its effector proteins into the host cell cytosol through formation of an oligomeric pore, which can assume heptameric or octameric states. By screening a highly directed library of PA mutants, we identified variants that complement each other to exclusively form octamers. These PA variants were individually nontoxic and demonstrated toxicity only when combined with their complementary partner. We then engineered requirements for activation by matrix metalloproteases and urokinase plasminogen activator into two of these variants. The resulting therapeutic toxin specifically targeted cells expressing both tumor associated proteases and completely stopped tumor growth in mice when used at a dose far below that which caused toxicity. This scheme for obtaining intercomplementing subunits can be employed with other oligomeric proteins and potentially has wide application. PMID:23393143

  15. Structure–Activity Relationship of Semicarbazone EGA Furnishes Photoaffinity Inhibitors of Anthrax Toxin Cellular Entry

    PubMed Central

    2014-01-01

    EGA, 1, prevents the entry of multiple viruses and bacterial toxins into mammalian cells by inhibiting vesicular trafficking. The cellular target of 1 is unknown, and a structure–activity relationship study was conducted in order to develop a strategy for target identification. A compound with midnanomolar potency was identified (2), and three photoaffinity labels were synthesized (3–5). For this series, the expected photochemistry of the phenyl azide moiety is a more important factor than the IC50 of the photoprobe in obtaining a successful photolabeling event. While 3 was the most effective reversible inhibitor of the series, it provided no protection to cells against anthrax lethal toxin (LT) following UV irradiation. Conversely, 5, which possessed weak bioactivity in the standard assay, conferred robust irreversible protection vs LT to cells upon UV photolysis. PMID:24900841

  16. Anthrax Toxin Receptor 1 Is Essential for Arteriogenesis in a Mouse Model of Hindlimb Ischemia

    PubMed Central

    Andersen, N. J.; Boguslawski, E. A.; Naidu, A. S.; Szot, C.; Bromberg-White, J. L.; Kits, K.; Kuk, C. Y.; Holton, L. E.; St. Croix, B.; Chambers, C. M.; Duesbery, N. S.

    2016-01-01

    Anthrax toxin receptor 1/tumor endothelial marker 8 (Antxr1 or TEM8) is up-regulated in tumor vasculature and serves as a receptor for anthrax toxin, but its physiologic function is unclear. The objective of this study was to evaluate the role of Antxr1 in arteriogenesis. The role of Antxr1 in arteriogenesis was tested by measuring gene expression and immunohistochemistry in a mouse model of hindlimb ischemia using wild-type and ANTXR1-/- mice. Additional tests were performed by measuring gene expression in in vitro models of fluid shear stress and hypoxia, as well as in human muscle tissues obtained from patients having peripheral artery disease. We observed that Antxr1 expression transiently increased in ischemic tissues following femoral artery ligation and that its expression was necessary for arteriogenesis. In the absence of Antxr1, the mean arterial lumen area in ischemic tissues decreased. Antxr1 mRNA and protein expression was positively regulated by fluid shear stress, but not by hypoxia. Furthermore, Antxr1 expression was elevated in human peripheral artery disease requiring lower extremity bypass surgery. These findings demonstrate an essential physiologic role for Antxr1 in arteriogenesis and peripheral artery disease, with important implications for managing ischemia and other arteriogenesis-dependent vascular diseases. PMID:26785120

  17. Anthrax Toxin Receptor 1 Is Essential for Arteriogenesis in a Mouse Model of Hindlimb Ischemia.

    PubMed

    Andersen, N J; Boguslawski, E A; Naidu, A S; Szot, C; Bromberg-White, J L; Kits, K; Kuk, C Y; Holton, L E; St Croix, B; Chambers, C M; Duesbery, N S

    2016-01-01

    Anthrax toxin receptor 1/tumor endothelial marker 8 (Antxr1 or TEM8) is up-regulated in tumor vasculature and serves as a receptor for anthrax toxin, but its physiologic function is unclear. The objective of this study was to evaluate the role of Antxr1 in arteriogenesis. The role of Antxr1 in arteriogenesis was tested by measuring gene expression and immunohistochemistry in a mouse model of hindlimb ischemia using wild-type and ANTXR1(-/-) mice. Additional tests were performed by measuring gene expression in in vitro models of fluid shear stress and hypoxia, as well as in human muscle tissues obtained from patients having peripheral artery disease. We observed that Antxr1 expression transiently increased in ischemic tissues following femoral artery ligation and that its expression was necessary for arteriogenesis. In the absence of Antxr1, the mean arterial lumen area in ischemic tissues decreased. Antxr1 mRNA and protein expression was positively regulated by fluid shear stress, but not by hypoxia. Furthermore, Antxr1 expression was elevated in human peripheral artery disease requiring lower extremity bypass surgery. These findings demonstrate an essential physiologic role for Antxr1 in arteriogenesis and peripheral artery disease, with important implications for managing ischemia and other arteriogenesis-dependent vascular diseases. PMID:26785120

  18. Reduction of immunogenicity of anthrax vaccines subjected to thermal stress, as measured by a toxin neutralization assay.

    PubMed

    Castelán-Vega, Juan; Corvette, Laura; Sirota, Lev; Arciniega, Juan

    2011-02-01

    We report that a toxin neutralization assay (TNA) can detect a decrease in the immunogenicity of anthrax vaccines as a consequence of brief exposure to elevated temperature. This attribute of TNA may help in adopting immunogenicity as a replacement of the current potency test, which involves protection from lethal challenge. PMID:21147935

  19. Reduction of Immunogenicity of Anthrax Vaccines Subjected to Thermal Stress, as Measured by a Toxin Neutralization Assay ▿

    PubMed Central

    Castelán-Vega, Juan; Corvette, Laura; Sirota, Lev; Arciniega, Juan

    2011-01-01

    We report that a toxin neutralization assay (TNA) can detect a decrease in the immunogenicity of anthrax vaccines as a consequence of brief exposure to elevated temperature. This attribute of TNA may help in adopting immunogenicity as a replacement of the current potency test, which involves protection from lethal challenge. PMID:21147935

  20. Auranofin Protects against Anthrax Lethal Toxin-Induced Activation of the Nlrp1b Inflammasome ▿

    PubMed Central

    Newman, Zachary L.; Sirianni, Nicole; Mawhinney, Christina; Lee, Margaret S.; Leppla, Stephen H.; Moayeri, Mahtab; Johansen, Lisa M.

    2011-01-01

    Anthrax lethal toxin (LT) is the major virulence factor for Bacillus anthracis. The lethal factor (LF) component of this bipartite toxin is a protease which, when transported into the cellular cytoplasm, cleaves mitogen-activated protein kinase kinase (MEK) family proteins and induces rapid toxicity in mouse macrophages through activation of the Nlrp1b inflammasome. A high-throughput screen was performed to identify synergistic LT-inhibitory drug combinations from within a library of approved drugs and molecular probes. From this screen we discovered that auranofin, an organogold compound with anti-inflammatory activity, strongly inhibited LT-mediated toxicity in mouse macrophages. Auranofin did not inhibit toxin transport into cells or MEK cleavage but inhibited both LT-mediated caspase-1 activation and caspase-1 catalytic activity. Thus, auranofin inhibited LT-mediated toxicity by preventing activation of the Nlrp1b inflammasome and the downstream actions that occur in response to the toxin. Idebenone, an analog of coenzyme Q, synergized with auranofin to increase its protective effect. We found that idebenone functions as an inhibitor of voltage-gated potassium channels and thus likely mediates synergy through inhibition of the potassium fluxes which have been shown to be required for Nlrp1b inflammasome activation. PMID:21149629

  1. Hijacking multivesicular bodies enables long-term and exosome-mediated long-distance action of anthrax toxin

    PubMed Central

    Abrami, Laurence; Brandi, Lucia; Moayeri, Mahtab; Brown, Michael J.; Krantz, Bryan A.; Leppla, Stephen H.; van der Goot, F. G.

    2013-01-01

    SUMMARY Anthrax Lethal Toxin is a classical AB-toxin comprised of two components, Protective Antigen (PA) and Lethal Factor (LF). Here we show that following assembly and endocytosis, PA forms a channel that translocates LF, not only into the cytosol, but also into the lumen of endosomal intraluminal vesicles (ILVs). These ILVs can fuse and release LF into the cytosol, where LF can proteolyze and disable host targets. We find that LF can persist in ILVs for days, fully sheltered from proteolytic degradation, both in vitro and in vivo. During this time ILV-localized LF can be transmitted to daughter cells upon cell division. In addition, LF-containing ILVs can be delivered to the extracellular medium as exosomes. These can deliver LF to the cytosol of naïve cells in a manner that is independent of the typical anthrax toxin-receptor trafficking pathway, while being sheltered from neutralizing extracellular factors of the immune system. PMID:24239351

  2. Anthrax lethal toxin disrupts intestinal barrier function and causes systemic infections with enteric bacteria.

    PubMed

    Sun, Chen; Fang, Hui; Xie, Tao; Auth, Roger D; Patel, Nayana; Murray, Patrick R; Snoy, Philip J; Frucht, David M

    2012-01-01

    A variety of intestinal pathogens have virulence factors that target mitogen activated protein kinase (MAPK) signaling pathways, including Bacillus anthracis. Anthrax lethal toxin (LT) has specific proteolytic activity against the upstream regulators of MAPKs, the MAPK kinases (MKKs). Using a murine model of intoxication, we show that LT causes the dose-dependent disruption of intestinal epithelial integrity, characterized by mucosal erosion, ulceration, and bleeding. This pathology correlates with an LT-dependent blockade of intestinal crypt cell proliferation, accompanied by marked apoptosis in the villus tips. C57BL/6J mice treated with intravenous LT nearly uniformly develop systemic infections with commensal enteric organisms within 72 hours of administration. LT-dependent intestinal pathology depends upon its proteolytic activity and is partially attenuated by co-administration of broad spectrum antibiotics, indicating that it is both a cause and an effect of infection. These findings indicate that targeting of MAPK signaling pathways by anthrax LT compromises the structural integrity of the mucosal layer, serving to undermine the effectiveness of the intestinal barrier. Combined with the well-described immunosuppressive effects of LT, this disruption of the intestinal barrier provides a potential mechanism for host invasion via the enteric route, a common portal of entry during the natural infection cycle of Bacillus anthracis. PMID:22438953

  3. Controlled release of an anthrax toxin-neutralizing antibody from hydrolytically degradable polyethylene glycol hydrogels.

    PubMed

    Liang, Yingkai; Coffin, Megan V; Manceva, Slobodanka D; Chichester, Jessica A; Jones, R Mark; Kiick, Kristi L

    2016-01-01

    In this study, hydrophilic and hydrolytically degradable poly (ethylene glycol) (PEG) hydrogels were formed via Michael-type addition and employed for sustained delivery of a monoclonal antibody against the protective antigen of anthrax. Taking advantage of the PEG-induced precipitation of the antibody, burst release from the matrix was avoided. These hydrogels were able to release active antibodies in a controlled manner from 14 days to as long as 56 days in vitro by varying the polymer architectures and molecular weights of the precursors. Analysis of the secondary and tertiary structure and the in vitro activity of the released antibody showed that the encapsulation and release did not affect the protein conformation or functionality. The results suggest the promise for developing PEG-based carriers for sustained release of therapeutic antibodies against toxins in various applications. PMID:26223817

  4. Trapping a translocating protein within the anthrax toxin channel: implications for the secondary structure of permeating proteins

    PubMed Central

    Jennings-Antipov, Laura D.; Jakes, Karen S.; Finkelstein, Alan

    2011-01-01

    Anthrax toxin consists of three proteins: lethal factor (LF), edema factor (EF), and protective antigen (PA). This last forms a heptameric channel, (PA63)7, in the host cell’s endosomal membrane, allowing the former two (which are enzymes) to be translocated into the cytosol. (PA63)7 incorporated into planar bilayer membranes forms a channel that translocates LF and EF, with the N terminus leading the way. The channel is mushroom-shaped with a cap containing the binding sites for EF and LF, and an ∼100 Å–long, 15 Å–wide stem. For proteins to pass through the stem they clearly must unfold, but is secondary structure preserved? To answer this question, we developed a method of trapping the polypeptide chain of a translocating protein within the channel and determined the minimum number of residues that could traverse it. We attached a biotin to the N terminus of LFN (the 263-residue N-terminal portion of LF) and a molecular stopper elsewhere. If the distance from the N terminus to the stopper was long enough to traverse the channel, streptavidin added to the trans side bound the N-terminal biotin, trapping the protein within the channel; if this distance was not long enough, streptavidin did not bind the N-terminal biotin and the protein was not trapped. The trapping rate was dependent on the driving force (voltage), the length of time it was applied, and the number of residues between the N terminus and the stopper. By varying the position of the stopper, we determined the minimum number of residues required to span the channel. We conclude that LFN adopts an extended-chain configuration as it translocates; i.e., the channel unfolds the secondary structure of the protein. We also show that the channel not only can translocate LFN in the normal direction but also can, at least partially, translocate LFN in the opposite direction. PMID:21402886

  5. Recent Developments in Anti-dotes Against Anthrax.

    PubMed

    Dhasmana, Neha; Singh, Lalit K; Bhaduri, Asani; Misra, Richa; Singh, Yogendra

    2014-01-01

    The etiologic agent of disease anthrax, Bacillus anthracis, causes recurrent outbreaks among the livestock and intermittent infections in humans across the world. Controlling animal infections by vaccination can minimize the incidence of disease in humans. Prevention of anthrax in occupationally exposed personnel is achieved through vaccination with either live spores or precipitates of culture supernatants from attenuated strains of B. anthracis. However, anthrax vaccination of the large human population is impractical as well as inappropriate. Broad-range antibiotics like amoxicillin, ciprofloxacin, clindamycin, streptomycin, and penicillin G are recommended for the treatment of human anthrax infections, but the threat of antibiotic resistant strains always remains. Moreover, in the absence of any specific symptom (s) during early infection, the diagnosis of anthrax is delayed causing elevated levels of anthrax toxin component which could be fatal. For these reasons, there is a need to develop new antimicrobial agents against virulent B. anthracis to effectively combat this fatal pathogen. Over the last two decades, extensive studies have been carried out to develop specific inhibitors against virulence factors of B. anthracis such as capsule, protective antigen, lethal factor and edema factor. Research has also been focused in developing inhibitors of anthrax toxin receptors (including the use of receptor decoys) and host furin endoproteases which are required for activation of toxin. This review highlights the recent progress made in developing the diverse countermeasures for anthrax infections targeting B. anthracis virulence factors and their counterparts in host. PMID:25174439

  6. Charge Requirements for Proton Gradient-driven Translocation of Anthrax Toxin*

    PubMed Central

    Brown, Michael J.; Thoren, Katie L.; Krantz, Bryan A.

    2011-01-01

    Anthrax lethal toxin is used as a model system to study protein translocation. The toxin is composed of a translocase channel, called protective antigen (PA), and an enzyme, called lethal factor (LF). A proton gradient (ΔpH) can drive LF unfolding and translocation through PA channels; however, the mechanism of ΔpH-mediated force generation, substrate unfolding, and establishment of directionality are poorly understood. One recent hypothesis suggests that the ΔpH may act through changes in the protonation state of residues in the substrate. Here we report the charge requirements of LF's amino-terminal binding domain (LFN) using planar lipid bilayer electrophysiology. We found that acidic residues are required in LFN to utilize a proton gradient for translocation. Constructs lacking negative charges in the unstructured presequence of LFN translocate independently of the ΔpH driving force. Acidic residues markedly increase the rate of ΔpH-driven translocation, and the presequence is optimized in its natural acidic residue content for efficient ΔpH-driven unfolding and translocation. We discuss a ΔpH-driven charge state Brownian ratchet mechanism for translocation, where glutamic and aspartic acid residues in the substrate are the “molecular teeth” of the ratchet. Our Brownian ratchet model includes a mechanism for unfolding and a novel role for positive charges, which we propose chaperone negative charges through the PA channel during ΔpH translocation. PMID:21507946

  7. Delivery of Non-Native Cargo into Mammalian Cells Using Anthrax Lethal Toxin.

    PubMed

    Rabideau, Amy E; Pentelute, Bradley Lether

    2016-06-17

    The intracellular delivery of peptide and protein therapeutics is a major challenge due to the plasma membrane, which acts as a barrier between the extracellular environment and the intracellular milieu. Over the past two decades, a nontoxic PA/LFN delivery platform derived from anthrax lethal toxin has been developed for the transport of non-native cargo into the cytosol of cells in order to understand the translocation process through a protective antigen (PA) pore and to probe intracellular biological functions. Enzyme-mediated ligation using sortase A and native chemical ligation are two facile methods used to synthesize these non-native conjugates, inaccessible by recombinant technology. Cargo molecules that translocate efficiently include enzymes from protein toxins, antibody mimic proteins, and peptides of varying lengths and non-natural amino acid compositions. The PA pore has been found to effectively convey over 30 known cargos other than native lethal factor (LF; i.e., non-native) with diverse sequences and functionalities on the LFN transporter protein. All together these studies demonstrated that non-native cargos must adopt an unfolded or extended conformation and contain a suitable charge composition in order to efficiently pass through the PA pore. This review provides insight into design parameters for the efficient delivery of new cargos using PA and LFN. PMID:27055654

  8. Anthrax infection.

    PubMed

    Sweeney, Daniel A; Hicks, Caitlin W; Cui, Xizhong; Li, Yan; Eichacker, Peter Q

    2011-12-15

    Bacillus anthracis infection is rare in developed countries. However, recent outbreaks in the United States and Europe and the potential use of the bacteria for bioterrorism have focused interest on it. Furthermore, although anthrax was known to typically occur as one of three syndromes related to entry site of (i.e., cutaneous, gastrointestinal, or inhalational), a fourth syndrome including severe soft tissue infection in injectional drug users is emerging. Although shock has been described with cutaneous anthrax, it appears much more common with gastrointestinal, inhalational (5 of 11 patients in the 2001 outbreak in the United States), and injectional anthrax. Based in part on case series, the estimated mortalities of cutaneous, gastrointestinal, inhalational, and injectional anthrax are 1%, 25 to 60%, 46%, and 33%, respectively. Nonspecific early symptomatology makes initial identification of anthrax cases difficult. Clues to anthrax infection include history of exposure to herbivore animal products, heroin use, or clustering of patients with similar respiratory symptoms concerning for a bioterrorist event. Once anthrax is suspected, the diagnosis can usually be made with Gram stain and culture from blood or surgical specimens followed by confirmatory testing (e.g., PCR or immunohistochemistry). Although antibiotic therapy (largely quinolone-based) is the mainstay of anthrax treatment, the use of adjunctive therapies such as anthrax toxin antagonists is a consideration. PMID:21852539

  9. Anthrax Infection

    PubMed Central

    Sweeney, Daniel A.; Hicks, Caitlin W.; Cui, Xizhong; Li, Yan

    2011-01-01

    Bacillus anthracis infection is rare in developed countries. However, recent outbreaks in the United States and Europe and the potential use of the bacteria for bioterrorism have focused interest on it. Furthermore, although anthrax was known to typically occur as one of three syndromes related to entry site of (i.e., cutaneous, gastrointestinal, or inhalational), a fourth syndrome including severe soft tissue infection in injectional drug users is emerging. Although shock has been described with cutaneous anthrax, it appears much more common with gastrointestinal, inhalational (5 of 11 patients in the 2001 outbreak in the United States), and injectional anthrax. Based in part on case series, the estimated mortalities of cutaneous, gastrointestinal, inhalational, and injectional anthrax are 1%, 25 to 60%, 46%, and 33%, respectively. Nonspecific early symptomatology makes initial identification of anthrax cases difficult. Clues to anthrax infection include history of exposure to herbivore animal products, heroin use, or clustering of patients with similar respiratory symptoms concerning for a bioterrorist event. Once anthrax is suspected, the diagnosis can usually be made with Gram stain and culture from blood or surgical specimens followed by confirmatory testing (e.g., PCR or immunohistochemistry). Although antibiotic therapy (largely quinolone-based) is the mainstay of anthrax treatment, the use of adjunctive therapies such as anthrax toxin antagonists is a consideration. PMID:21852539

  10. Constitutive MEK1 activation rescues anthrax lethal toxin-induced vascular effects in vivo.

    PubMed

    Bolcome, Robert E; Chan, Joanne

    2010-12-01

    Anthrax lethal toxin (LT) increases vascular leakage in a number of mammalian models and in human anthrax disease. Using a zebrafish model, we determined that vascular delivery of LT increased permeability, which was phenocopied by treatment with a selective chemical inhibitor of MEK1 and MEK2 (also known as mitogen-activated protein kinase [MAPK] kinase, MEK, or MKK). Here we investigate further the role of MEK1/phospho-ERK (pERK) in the action of LT. Overexpression of wild-type zebrafish MEK1 at high levels did not induce detrimental effects. However, a constitutively activated version, MEK1(S219D,S223D) (MEK1DD), induced early defects in embryonic development that correlated with increased ERK/MAPK phosphorylation. To bypass these early developmental defects and to provide a genetic tool for examining the action of lethal factor (LF), we generated inducible transgenic zebrafish lines expressing either wild-type or activated MEK1 under the control of a heat shock promoter. Remarkably, induction of MEK1DD transgene expression prior to LT delivery prevented vascular damage, while the wild-type MEK1 line did not. In the presence of both LT and MEK1DD transgene expression, cardiovascular development and function proceeded normally in most embryos. The resistance to microsphere leakage in transgenic animals demonstrated a protective role against LT-induced vascular permeability. A consistent increase in ERK phosphorylation among LT-resistant MEK1DD transgenic animals provided additional confirmation of transgene activation. These findings provide a novel genetic approach to examine mechanism of action of LT in vivo through one of its known targets. This approach may be generally applied to investigate additional pathogen-host interactions and to provide mechanistic insights into host signaling pathways affected by pathogen entry. PMID:20855511

  11. Temperature-mediated recombinant anthrax protective antigen aggregate development: Implications for toxin formation and immunogenicity.

    PubMed

    Amador-Molina, Juan C; Valerdi-Madrigal, Esther D; Domínguez-Castillo, Rocío I; Sirota, Lev A; Arciniega, Juan L

    2016-07-29

    Anthrax vaccines containing recombinant PA (rPA) as the only antigen face a stability issue: rPA forms aggregates in solution after exposure to temperatures ⩾40°C, thus losing its ability to form lethal toxin (LeTx) with Lethal Factor. To study rPA aggregation's impact on immune response, we subjected rPA to several time and temperature combinations. rPA treated at 50°C for 30min formed high mass aggregates when analyzed by gel electrophoresis and failed to form LeTx as measured by a macrophage lysis assay (MLA). Aggregated rPA-formed LeTx was about 30 times less active than LeTx containing native rPA. Mice immunized with heat-treated rPA combined with Al(OH)3 developed antibody titers about 49 times lower than mice immunized with native rPA, as measured by a Toxicity Neutralization Assay (TNA). Enzyme Linked Immunosorbent Assay (ELISA) of the same immune sera showed anti-rPA titers only 2-7 times lower than titers elicited by native rPA. Thus, rPA's ability to form LeTx correlates with its production of neutralizing antibodies, and aggregation significantly impairs the protein's antibody response. However, while these findings suggest MLA has some value as an in-process quality test for rPA in new anthrax vaccines, they also confirm the superiority of TNA for use in vaccine potency. PMID:27364097

  12. Edema

    MedlinePlus

    Edema means swelling caused by fluid in your body's tissues. It usually occurs in the feet, ankles ... it can involve your entire body. Causes of edema include Eating too much salt Sunburn Heart failure ...

  13. An anthrax toxin variant with an improved activity in tumor targeting

    PubMed Central

    Wein, Alexander N.; Peters, Diane E.; Valivullah, Zaheer; Hoover, Benjamin J.; Tatineni, Aparna; Ma, Qian; Fattah, Rasem; Bugge, Thomas H.; Leppla, Stephen H.; Liu, Shihui

    2015-01-01

    Anthrax lethal toxin (LT) is an A-B type toxin secreted by Bacillus anthracis, consisting of the cellular binding moiety, protective antigen (PA), and the catalytic moiety, lethal factor (LF). To target cells, PA binds to cell-surface receptors and is then proteolytically processed forming a LF-binding competent PA oligomer where each LF binding site is comprised of three subsites on two adjacent PA monomers. We previously generated PA-U2-R200A, a urokinase-activated PA variant with LF-binding subsite II residue Arg200 mutated to Ala, and PA-L1-I210A, a matrix metalloproteinase-activated PA variant with subsite III residue Ile210 mutated to Ala. PA-U2-R200A and PA-L1-I210A displayed reduced cytotoxicity when used singly. However, when combined, they formed LF-binding competent heterogeneous oligomers by intermolecular complementation, and achieved high specificity in tumor targeting. Nevertheless, each of these proteins, in particular PA-L1-I210A, retained residual LF-binding ability. In this work, we screened a library containing all possible amino acid substitutions for LF-binding site to find variants with activity strictly dependent upon intermolecular complementation. PA-I207R was identified as an excellent replacement for the original clockwise-side variant, PA-I210A. Consequently, the new combination of PA-L1-I207R and PA-U2-R200A showed potent anti-tumor activity and low toxicity, exceeding the performance of the original combination, and warranting further investigation. PMID:26584669

  14. Solubilization and characterization of the anthrax toxin pore in detergent micelles

    PubMed Central

    Vernier, Gregory; Wang, Jie; Jennings, Laura D; Sun, Jianjun; Fischer, Audrey; Song, Likai; Collier, R John

    2009-01-01

    Proteolytically activated Protective Antigen (PA) moiety of anthrax toxin self-associates to form a heptameric ring-shaped oligomer (the prepore). Acidic pH within the endosome converts the prepore to a pore that serves as a passageway for the toxin's enzymatic moieties to cross the endosomal membrane. Prepore is stable in solution under mildly basic conditions, and lowering the pH promotes a conformational transition to an insoluble pore-like state. N-tetradecylphosphocholine (FOS14) was the only detergent among 110 tested that prevented aggregation without dissociating the multimer into its constituent subunits. FOS14 maintained the heptamers as monodisperse, insertion-competent 440-kDa particles, which formed channels in planar phospholipid bilayers with the same unitary conductance and ability to translocate a model substrate protein as channels formed in the absence of detergent. Electron paramagnetic resonance analysis detected pore-like conformational changes within PA on solubilization with FOS14, and electron micrograph images of FOS14-solubilized pore showed an extended, mushroom-shaped structure. Circular dichroïsm measurements revealed an increase in α helix and a decrease in β structure in pore formation. Spectral changes caused by a deletion mutation support the hypothesis that the 2β2-2β3 loop transforms into the transmembrane segment of the β-barrel stem of the pore. Changes caused by selected point mutations indicate that the transition to α structure is dependent on residues of the luminal 2β11-2β12 loop that are known to affect pore formation. Stabilizing the PA pore in solution with FOS14 may facilitate further structural analysis and a more detailed understanding of the folding pathway by which the pore is formed. PMID:19609933

  15. Electrochemical DNA sensor for anthrax toxin activator gene atxA-detection of PCR amplicons.

    PubMed

    Das, Ritu; Goel, Ajay K; Sharma, Mukesh K; Upadhyay, Sanjay

    2015-12-15

    We report the DNA probe functionalized electrochemical genosensor for the detection of Bacillus anthracis, specific towards the regulatory gene atxA. The DNA sensor is fabricated on electrochemically deposited gold nanoparticle on self assembled layer of (3-Mercaptopropyl) trimethoxysilane (MPTS) on GC electrode. DNA hybridization is monitored by differential pulse voltammogram (DPV). The modified GC electrode is characterized by atomic force microscopy (AFM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) method. We also quantified the DNA probe density on electrode surface by the chronocoulometric method. The detection is specific and selective for atxA gene by DNA probe on the electrode surface. No report is available for the detection of B. anthracis by using atxA an anthrax toxin activator gene. In the light of real and complex sample, we have studied the PCR amplicons of 303, 361 and 568 base pairs by using symmetric and asymmetric PCR approaches. The DNA probe of atxA gene efficiently hybridizes with different base pairs of PCR amplicons. The detection limit is found to be 1.0 pM (S/N ratio=3). The results indicate that the DNA sensor is able to detect synthetic target as well as PCR amplicons of different base pairs. PMID:26257186

  16. Anthrax lethal toxin and the induction of CD4 T cell immunity.

    PubMed

    Ascough, Stephanie; Ingram, Rebecca J; Altmann, Daniel M

    2012-10-01

    Bacillus anthracis secretes exotoxins which act through several mechanisms including those that can subvert adaptive immunity with respect both to antigen presenting cell and T cell function. The combination of Protective Antigen (PA) and Lethal Factor (LF) forming Lethal Toxin (LT), acts within host cells to down-regulate the mitogen activated protein kinase (MAPK) signaling cascade. Until recently the MAPK kinases were the only known substrate for LT; over the past few years it has become evident that LT also cleaves Nlrp1, leading to inflammasome activation and macrophage death. The predicted downstream consequences of subverting these important cellular pathways are impaired antigen presentation and adaptive immunity. In contrast to this, recent work has indicated that robust memory T cell responses to B. anthracis antigens can be identified following natural anthrax infection. We discuss how LT affects the adaptive immune response and specifically the identification of B. anthracis epitopes that are both immunogenic and protective with the potential for inclusion in protein sub-unit based vaccines. PMID:23162703

  17. Delivery of Antibody Mimics into Mammalian Cells via Anthrax Toxin Protective Antigen

    PubMed Central

    Liao, Xiaoli; Rabideau, Amy E; Pentelute, Bradley L

    2014-01-01

    Antibody mimics have significant scientific and therapeutic utility for the disruption of protein–protein interactions inside cells; however, their delivery to the cell cytosol remains a major challenge. Here we show that protective antigen (PA), a component of anthrax toxin, efficiently transports commonly used antibody mimics to the cytosol of mammalian cells when conjugated to the N-terminal domain of LF (LFN). In contrast, a cell-penetrating peptide (CPP) was not able to deliver any of these antibody mimics into the cell cytosol. The refolding and binding of a transported tandem monobody to Bcr-Abl (its protein target) in chronic myeloid leukemia cells were confirmed by co-immunoprecipitation. We also observed inhibition of Bcr-Abl kinase activity and induction of apoptosis caused by the monobody. In a separate case, we show disruption of key interactions in the MAPK signaling pathway after PA-mediated delivery of an affibody binder that targets hRaf-1. We show for the first time that PA can deliver bioactive antibody mimics to disrupt intracellular protein–protein interactions. This technology adds a useful tool to expand the applications of these modern agents to the intracellular milieu. PMID:25250705

  18. The Cytoplasmic Domain of Anthrax Toxin Receptor 1 Affects Binding of the Protective Antigen▿

    PubMed Central

    Go, Mandy Y.; Chow, Edith M. C.; Mogridge, Jeremy

    2009-01-01

    The protective antigen (PA) component of anthrax toxin binds the I domain of the receptor ANTXR1. Integrin I domains convert between open and closed conformations that bind ligand with high and low affinities, respectively; this process is regulated by signaling from the cytoplasmic domains. To assess whether intracellular signals might influence the interaction between ANTXR1 and PA, we compared two splice variants of ANTXR1 that differ only in their cytoplasmic domains. We found that cells expressing ANTXR1 splice variant 1 (ANTXR1-sv1) bound markedly less PA than did cells expressing a similar level of the shorter splice variant ANTXR1-sv2. ANTXR1-sv1 but not ANTXR1-sv2 associated with the actin cytoskeleton, although disruption of the cytoskeleton did not affect binding of ANTXR-sv1 to PA. Introduction of a cytoplasmic domain missense mutation found in the related receptor ANTXR2 in a patient with juvenile hyaline fibromatosis impaired actin association and increased binding of PA to ANTXR1-sv1. These results suggest that ANTXR1 has two affinity states that may be modulated by cytoplasmic signals. PMID:18936178

  19. Differential Dependence on N-Glycosylation of Anthrax Toxin Receptors CMG2 and TEM8

    PubMed Central

    Friebe, Sarah; Deuquet, Julie; van der Goot, F. Gisou

    2015-01-01

    ANTXR 1 and 2, also known as TEM8 and CMG2, are two type I membrane proteins, which have been extensively studied for their role as anthrax toxin receptors, but with a still elusive physiological function. Here we have analyzed the importance of N-glycosylation on folding, trafficking and ligand binding of these closely related proteins. We find that TEM8 has a stringent dependence on N-glycosylation. The presence of at least one glycan on each of its two extracellular domains, the vWA and Ig-like domains, is indeed necessary for efficient trafficking to the cell surface. In the absence of any N-linked glycans, TEM8 fails to fold correctly and is recognized by the ER quality control machinery. Expression of N-glycosylation mutants reveals that CMG2 is less vulnerable to sugar loss. The absence of N-linked glycans in one of the extracellular domains indeed has little impact on folding, trafficking or receptor function of the wild type protein expressed in tissue culture cells. N-glycans do, however, seem required in primary fibroblasts from human patients. Here, the presence of N-linked sugars increases the tolerance to mutations in cmg2 causing the rare genetic disease Hyaline Fibromatosis Syndrome. It thus appears that CMG2 glycosylation provides a buffer towards genetic variation by promoting folding of the protein in the ER lumen. PMID:25781883

  20. Anthrax Lethal Toxin Induces Acute Diastolic Dysfunction in Rats Through Disruption of the Phospholamban Signaling Network

    PubMed Central

    Golden, Honey B.; Watson, Linley E.; Nizamutdinov, Damir; Feng, Hao; Gerilechaogetu, Fnu; Lal, Hind; Verma, Suresh K.; Mukhopadhyay, Swagoto; Foster, Donald M.; Dillmann, Wolfgang H.; Dostal, D.E.

    2013-01-01

    Background Anthrax lethal toxin (LT), secreted by Bacillus anthracis, causes severe cardiac dysfunction by unknown mechanisms. LT specifically cleaves the docking domains of MAPKK (MEKs); thus, we hypothesized that LT directly impairs cardiac function through dysregulation of MAPK signaling mechanisms. Methods and Results In a time-course study of LT toxicity, echocardiography revealed acute diastolic heart failure accompanied by pulmonary regurgitation and left atrial dilation in adult Sprague-Dawley rats at time points corresponding to dysregulated JNK, phospholamban (PLB) and protein phosphatase 2A (PP2A) myocardial signaling. Using isolated rat ventricular myocytes, we identified the MEK7-JNK1-PP2A-PLB signaling axis to be important for regulation of intracellular calcium (Ca2+i) handling, PP2A activation and targeting of PP2A-B56α to Ca2+i handling proteins, such as PLB. Through a combination of gain-of-function and loss-of-function studies, we demonstrated that over-expression of MEK7 protects against LT-induced PP2A activation and Ca2+i dysregulation through activation of JNK1. Moreover, targeted phosphorylation of PLB-Thr17 by Akt improved sarcoplasmic reticulum Ca2+i release and reuptake during LT toxicity. Co-immunoprecipitation experiments further revealed the pivotal role of MEK7-JNK-Akt complex formation for phosphorylation of PLB-Thr17 during acute LT toxicity. Conclusions Our findings support a cardiogenic mechanism of LT-induced diastolic dysfunction, by which LT disrupts JNK1 signaling and results in Ca2+i dysregulation through diminished phosphorylation of PLB by Akt and increased dephosphorylation of PLB by PP2A. Integration of the MEK7-JNK1 signaling module with Akt represents an important stress-activated signalosome that may confer protection to sustain cardiac contractility and maintain normal levels of Ca2+i through PLB-T17 phosphorylation. PMID:23907041

  1. Nonallergic Eyelid Edema After Botulinum Toxin Type A Injection: Case Report and Review of Literature.

    PubMed

    Chang, Yin-Shuo; Chang, Chang-Cheng; Shen, Jen-Hsiang; Chen, Yu-Tsung; Chan, Karen Kar-Wun

    2015-09-01

    Periocular botulinum toxin type A (BoNTA) injections are generally safe. Ptosis is the most common adverse effect, whereas eyelid edema is rarely reported. There is no consensus on the latter's incidence, clinical course, or treatment strategy. Here we managed a 59-year-old woman who received BoNTA injections to her forehead, glabella, and eye corner. At 3-day follow-up, she presented with painless, nonpruritic, bilateral periorbital edema, and erythema. Preliminary diagnosis was a local allergic reaction, and topical corticosteroid was administered, but upon lack of improvement, edema secondary to venous and lymphatic congestion was hypothesized, and she was advised to apply hot pads over her eyes, blink frequently, and massage the area. Her eyelid edema resolved 2 weeks later. At 4-month follow-up, the patient requested and received another course of BoNTA at half the dose. Frequent blinking was instructed, and the patient reported a satisfactory outcome with no adverse effects. In our literature review, incidence of BoNTA-induced eyelid edema was 1.4% and showed Asian tendency. Although rare, BoNTA-induced periorbital edema is self-limiting, and normally resolves in 2 to 4 weeks without medical treatment. Patients at risk for edema, including Asian ethnicity, dermatochalasis, and poor periocular muscle tone, are advised to receive injections at half the dosage. Examination of the function and tone of the orbicularis oculi and levator palpebrae superioris muscles before treatment is recommended, and application of hot pads over the eyes, frequent blinking in the morning, and self-massage of the affected area to increase venous return have demonstrated to improve outcome. PMID:26402825

  2. Genetically modified anthrax lethal toxin safely delivers whole HIV protein antigens into the cytosol to induce T cell immunity

    NASA Astrophysics Data System (ADS)

    Lu, Yichen; Friedman, Rachel; Kushner, Nicholas; Doling, Amy; Thomas, Lawrence; Touzjian, Neal; Starnbach, Michael; Lieberman, Judy

    2000-07-01

    Bacillus anthrax lethal toxin can be engineered to deliver foreign proteins to the cytosol for antigen presentation to CD8 T cells. Vaccination with modified toxins carrying 8-9 amino acid peptide epitopes induces protective immunity in mice. To evaluate whether large protein antigens can be used with this system, recombinant constructs encoding several HIV antigens up to 500 amino acids were produced. These candidate HIV vaccines are safe in animals and induce CD8 T cells in mice. Constructs encoding gag p24 and nef stimulate gag-specific CD4 proliferation and a secondary cytotoxic T lymphocyte response in HIV-infected donor peripheral blood mononuclear cells in vitro. These results lay the foundation for future clinical vaccine studies.

  3. Genetically modified anthrax lethal toxin safely delivers whole HIV protein antigens into the cytosol to induce T cell immunity

    PubMed Central

    Lu, Yichen; Friedman, Rachel; Kushner, Nicholas; Doling, Amy; Thomas, Lawrence; Touzjian, Neal; Starnbach, Michael; Lieberman, Judy

    2000-01-01

    Bacillus anthrax lethal toxin can be engineered to deliver foreign proteins to the cytosol for antigen presentation to CD8 T cells. Vaccination with modified toxins carrying 8–9 amino acid peptide epitopes induces protective immunity in mice. To evaluate whether large protein antigens can be used with this system, recombinant constructs encoding several HIV antigens up to 500 amino acids were produced. These candidate HIV vaccines are safe in animals and induce CD8 T cells in mice. Constructs encoding gag p24 and nef stimulate gag-specific CD4 proliferation and a secondary cytotoxic T lymphocyte response in HIV-infected donor peripheral blood mononuclear cells in vitro. These results lay the foundation for future clinical vaccine studies. PMID:10884430

  4. Disarmed anthrax toxin delivers antisense oligonucleotides and siRNA with high efficiency and low toxicity.

    PubMed

    Dyer, Paul D R; Shepherd, Thomas R; Gollings, Alexander S; Shorter, Susan A; Gorringe-Pattrick, Monique A M; Tang, Chun-Kit; Cattoz, Beatrice N; Baillie, Les; Griffiths, Peter C; Richardson, Simon C W

    2015-12-28

    Inefficient cytosolic delivery and vector toxicity contribute to the limited use of antisense oligonucleotides (ASOs) and siRNA as therapeutics. As anthrax toxin (Atx) accesses the cytosol, the purpose of this study was to evaluate the potential of disarmed Atx to deliver either ASOs or siRNA. We hypothesized that this delivery strategy would facilitate improved transfection efficiency while eliminating the toxicity seen for many vectors due to membrane destabilization. Atx complex formation with ASOs or siRNA was achieved via the in-frame fusion of either Saccharomyces cerevisiae GAL4 or Homo sapien sapien PKR (respectively) to a truncation of Atx lethal factor (LFn), which were used with Atx protective antigen (PA). Western immunoblotting confirmed the production of: LFN-GAL4, LFn-PKR and PA which were detected at ~45.9 kDa, ~37 kDa, and ~83 kDa respectively and small angle neutron scattering confirmed the ability of PA to form an annular structure with a radius of gyration of 7.0 ± 1.0 nm when placed in serum. In order to form a complex with LFn-GAL4, ASOs were engineered to contain a double-stranded region, and a cell free in vitro translation assay demonstrated that no loss of antisense activity above 30 pmol ASO was evident. The in vitro toxicity of both PA:LFn-GAL4:ASO and PA:LFn-PKR:siRNA complexes was low (IC50>100 μg/mL in HeLa and Vero cells) and subcellular fractionation in conjunction with microscopy confirmed the detection of LFn-GAL4 or LFn-PKR in the cytosol. Syntaxin5 (Synt5) was used as a model target gene to determine pharmacological activity. The PA:LFn-GAL4:ASO complexes had transfection efficiency approximately equivalent to Nucleofection® over a variety of ASO concentrations (24h post-transfection) and during a 72 h time course. In HeLa cells, at 200 pmol ASO (with PA:LFN-GAL4), 5.4 ± 2.0% Synt5 expression was evident relative to an untreated control after 24h. Using 200 pmol ASOs, Nucleofection® reduced Synt5 expression to 8.1 ± 2

  5. Micropatterned Macrophage Analysis Reveals Global Cytoskeleton Constraints Induced by Bacillus anthracis Edema Toxin

    PubMed Central

    Trescos, Yannick; Tessier, Emilie; Rougeaux, Clémence; Goossens, Pierre L.

    2015-01-01

    Bacillus anthracis secretes the edema toxin (ET) that disrupts the cellular physiology of endothelial and immune cells, ultimately affecting the adherens junction integrity of blood vessels that in turn leads to edema. The effects of ET on the cytoskeleton, which is critical in cell physiology, have not been described thus far on macrophages. In this study, we have developed different adhesive micropatterned surfaces (L and crossbow) to control the shape of bone marrow-derived macrophages (BMDMs) and primary peritoneal macrophages. We found that macrophage F-actin cytoskeleton adopts a specific polar organization slightly different from classical human HeLa cells on the micropatterns. Moreover, ET induced a major quantitative reorganization of F-actin within 16 h with a collapse at the nonadhesive side of BMDMs along the nucleus. There was an increase in size and deformation into a kidney-like shape, followed by a decrease in size that correlates with a global cellular collapse. The collapse of F-actin was correlated with a release of focal adhesion on the patterns and decreased cell size. Finally, the cell nucleus was affected by actin reorganization. By using this technology, we could describe many previously unknown macrophage cellular dysfunctions induced by ET. This novel tool could be used to analyze more broadly the effects of toxins and other virulence factors that target the cytoskeleton. PMID:26015478

  6. Anthrax Toxin Protective Antigen: Inhibition of Channel Function by Chloroquine and Related Compounds and Study of Binding Kinetics Using the Current Noise Analysis

    PubMed Central

    Orlik, Frank; Schiffler, Bettina; Benz, Roland

    2005-01-01

    Protective antigen (PA) of the tripartite anthrax toxin binds to a cell surface receptor and mediates the transport of two enzymatic components, edema factor and lethal factor, into the cytosol of host cells. Here recombinant PA63 from Bacillus anthracis was reconstituted into artificial lipid bilayer membranes and formed ion permeable channels. The heptameric PA63-channel contains a binding site for 4-aminoquinolones, which block ion transport through PA in vitro. This result allowed a detailed investigation of ligand binding and the stability constants for the binding of chloroquine, fluphenazine, and quinacrine to the binding site inside the PA63-channel were determined using titration experiments. Open PA63-channels exhibit 1/f noise in the frequency range between 1 and 100 Hz, whereas the spectral density of the ligand-induced current noise was of Lorentzian type. The analysis of the power density spectra allowed the evaluation of the on- and off-rate constants (\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} \\begin{equation*}k_{1}\\end{equation*}\\end{document} and \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} \\begin{equation*}k_{-1}\\end{equation*}\\end{document}) of ligand binding. The on-rate constants of ligand binding were between 106 and 108 M−1 s−1 and were dependent on the ionic strength of the aqueous phase, sidedness of ligand addition, as well as the orientation and intensity of the applied electric field. The off-rates varied between ∼10 s−1 and 2600 s−1 and depended mainly on the structure of the ligand. PMID:15596516

  7. Affinity binding of antibodies to supermacroporous cryogel adsorbents with immobilized protein A for removal of anthrax toxin protective antigen.

    PubMed

    Ingavle, Ganesh C; Baillie, Les W J; Zheng, Yishan; Lis, Elzbieta K; Savina, Irina N; Howell, Carol A; Mikhalovsky, Sergey V; Sandeman, Susan R

    2015-05-01

    Polymeric cryogels are efficient carriers for the immobilization of biomolecules because of their unique macroporous structure, permeability, mechanical stability and different surface chemical functionalities. The aim of the study was to demonstrate the potential use of macroporous monolithic cryogels for biotoxin removal using anthrax toxin protective antigen (PA), the central cell-binding component of the anthrax exotoxins, and covalent immobilization of monoclonal antibodies. The affinity ligand (protein A) was chemically coupled to the reactive hydroxyl and epoxy-derivatized monolithic cryogels and the binding efficiencies of protein A, monoclonal antibodies to the cryogel column were determined. Our results show differences in the binding capacity of protein A as well as monoclonal antibodies to the cryogel adsorbents caused by ligand concentrations, physical properties and morphology of surface matrices. The cytotoxicity potential of the cryogels was determined by an in vitro viability assay using V79 lung fibroblast as a model cell and the results reveal that the cryogels are non-cytotoxic. Finally, the adsorptive capacities of PA from phosphate buffered saline (PBS) were evaluated towards a non-glycosylated, plant-derived human monoclonal antibody (PANG) and a glycosylated human monoclonal antibody (Valortim(®)), both of which were covalently attached via protein A immobilization. Optimal binding capacities of 108 and 117 mg/g of antibody to the adsorbent were observed for PANG attached poly(acrylamide-allyl glycidyl ether) [poly(AAm-AGE)] and Valortim(®) attached poly(AAm-AGE) cryogels, respectively, This indicated that glycosylation status of Valortim(®) antibody could significantly increase (8%) its binding capacity relative to the PANG antibody on poly(AAm-AGE)-protien-A column (p < 0.05). The amounts of PA which remained in the solution after passing PA spiked PBS through PANG or Valortim bound poly(AAm-AGE) cryogel were significantly (p < 0

  8. Anthrax Toxin Receptor 1 / Tumor Endothelial Marker 8: Mutation of Conserved Inserted Domain Residues Overrides Cytosolic Control of Protective Antigen Binding†

    PubMed Central

    Ramey, Jordan D.; Villareal, Valerie A.; Ng, Charles; Ward, Sabrina; Xiong, Jian-Ping; Clubb, Robert T.; Bradley, Kenneth A.

    2010-01-01

    Anthrax toxin receptor 1 (ANTXR1) / tumor endothelial marker 8 (TEM8) is one of two known proteinaceous cell surface anthrax toxin receptors. A metal ion dependent adhesion site (MIDAS) present in the integrin-like inserted (I) domain of ANTXR1 mediates the binding of the anthrax toxin subunit, protective antigen (PA). Here we provide evidence that single point mutations in the I domain can override regulation of ANTXR1 ligand-binding activity mediated by intracellular signals. A previously reported MIDAS-mutant of ANTXR1 (T118A) was found to retain normal metal ion binding and secondary structure but failed to bind PA, consistent with a locked inactive state. Conversely, mutation of a conserved I domain phenylalanine residue to a tryptophan (F205W) increased the proportion of cell-surface ANTXR1 that bound PA, consistent with a locked active state. Interestingly, the KD and total amount of PA bound by the isolated ANTXR1 I domain was not affected by the F205W mutation, indicating that ANTXR1 is preferentially found in the active state in the absence of inside-out signaling. Circular dichroism (CD) spectroscopy and 1H-15N heteronuclear single quantum coherence (HSQC) nuclear magnetic resonance (NMR) revealed that structural changes between T118A, F205W and WT I domains were minor despite a greater than 103-fold difference in their abilities to bind toxin. Regulation of toxin binding has important implications for the design of toxin inhibitors and for the targeting of ANTXR1 for anti-tumor therapies. PMID:20690680

  9. Anthrax of the gastrointestinal tract.

    PubMed

    Sirisanthana, Thira; Brown, Arthur E

    2002-07-01

    When swallowed, anthrax spores may cause lesions from the oral cavity to the cecum. Gastrointestinal anthrax is greatly underreported in rural disease-endemic areas of the world. The apparent paucity of this form of anthrax reflects the lack of facilities able to make the diagnosis in these areas. The spectrum of disease, ranging from subclinical infection to death, has not been fully recognized. In some community-based studies, cases of gastrointestinal anthrax outnumbered those of cutaneous anthrax. The oropharyngeal variant, in particular, is unfamiliar to most physicians. The clinical features of oropharyngeal anthrax include fever and toxemia, inflammatory lesion(s) in the oral cavity or oropharynx, enlargement of cervical lymph nodes associated with edema of the soft tissue of the cervical area, and a high case-fatality rate. Awareness of gastrointestinal anthrax in a differential diagnosis remains important in anthrax-endemic areas but now also in settings of possible bioterrorism. PMID:12095428

  10. Ligand-induced expansion of the S1' site in the anthrax toxin lethal factor.

    PubMed

    Maize, Kimberly M; Kurbanov, Elbek K; Johnson, Rodney L; Amin, Elizabeth Ambrose; Finzel, Barry C

    2015-12-21

    The Bacillus anthracis lethal factor (LF) is one component of a tripartite exotoxin partly responsible for persistent anthrax cytotoxicity after initial bacterial infection. Inhibitors of the zinc metalloproteinase have been investigated as potential therapeutic agents, but LF is a challenging target because inhibitors lack sufficient selectivity or possess poor pharmaceutical properties. These structural studies reveal an alternate conformation of the enzyme, induced upon binding of specific inhibitors, that opens a previously unobserved deep pocket termed S1'(∗) which might afford new opportunities to design selective inhibitors that target this subsite. PMID:26578066

  11. Ligand-induced expansion of the S1' site in the anthrax toxin lethal factor

    SciTech Connect

    Maize, Kimberly M.; Kurbanov, Elbek K.; Johnson, Rodney L.; Amin, Elizabeth Ambrose; Finzel, Barry C.

    2015-11-11

    The Bacillus anthracis lethal factor (LF) is one component of a tripartite exotoxin partly responsible for persistent anthrax cytotoxicity after initial bacterial infection. Inhibitors of the zinc metalloproteinase have been investigated as potential therapeutic agents, but LF is a challenging target because inhibitors lack sufficient selectivity or possess poor pharmaceutical properties. These structural studies reveal an alternate conformation of the enzyme, induced upon binding of specific inhibitors, that opens a previously unobserved deep pocket termed S1'* which might afford new opportunities to design selective inhibitors that target this subsite.

  12. Anthrax: Diagnosis

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Anthrax Note: Javascript is disabled or is not supported ... message, please visit this page: About CDC.gov . Anthrax Basic Information Types of Anthrax Cutaneous Anthrax Inhalation ...

  13. Anthrax lethal toxin inhibits translation of hypoxia-inducible factor 1α and causes decreased tolerance to hypoxic stress.

    PubMed

    Ouyang, Weiming; Torigoe, Chikako; Fang, Hui; Xie, Tao; Frucht, David M

    2014-02-14

    Hypoxia is considered to be a contributor to the pathology associated with administration of anthrax lethal toxin (LT). However, we report here that serum lactate levels in LT-treated mice are reduced, a finding inconsistent with the anaerobic metabolism expected to occur during hypoxia. Reduced lactate levels are also observed in the culture supernatants of LT-treated cells. LT inhibits the accumulation of hypoxia-inducible factor (HIF)-1α, a subunit of HIF-1, the master regulator directing cellular responses to hypoxia. The toxin has no effect on the transcription or protein turnover of HIF-1α, but instead it acts to inhibit HIF-1α translation. LT treatment diminishes phosphorylation of eIF4B, eIF4E, and rpS6, critical components of the intracellular machinery required for HIF-1α translation. Moreover, blockade of MKK1/2-ERK1/2, but not p38 or JNK signaling, lowers HIF-1α protein levels in both normoxic and hypoxic conditions, consistent with a role for MKK1 and MKK2 as the major targets of LT responsible for the inhibition of HIF-1α translation. The physiological importance of the LT-induced translation blockade is demonstrated by the finding that LT treatment decreases the survival of hepatocyte cell lines grown in hypoxic conditions, an effect that is overcome by preinduction of HIF-1α. Taken together, these data support a role for LT in dysregulating HIF-1α and thereby disrupting homeostatic responses to hypoxia, an environmental characteristic of certain tissues at baseline and/or during disseminated infection with Bacillus anthracis. PMID:24366872

  14. Development of an edema factor-mediated cAMP-induction bioassay for detecting antibody-mediated neutralization of anthrax protective antigen.

    PubMed

    Zmuda, Jonathan F; Zhang, Linyi; Richards, Terri; Pham, Quyen; Zukauskas, David; Pierre, Jennifer L; Laird, Michael W; Askins, Janine; Choi, Gil H

    2005-03-01

    Intoxication of mammalian cells by Bacillus anthracis requires the coordinate activity of three distinct bacterial proteins: protective antigen (PA), edema factor (EF), and lethal factor (LF). Among these proteins, PA has become the major focus of work on monoclonal antibodies and vaccines designed to treat or prevent anthrax infection since neither EF nor LF is capable of inducing cellular toxicity in its absence. Here, we present the development of a sensitive, precise, and biologically relevant bioassay platform capable of quantifying antibody-mediated PA neutralization. This bioassay is based on the ability of PA to bind and shuttle EF, a bacterial adenylate cyclase, into mammalian cells leading to an increase in cAMP that can be quantified using a sensitive chemiluminescent ELISA. The results of this study indicate that the cAMP-induction assay possesses the necessary performance characteristics for use as both a potency-indicating release assay in a quality control setting and as a surrogate pharmacodynamic marker for ensuring the continued bioactivity of therapeutic antibodies against PA during clinical trials. PMID:15847796

  15. Passive Immunotherapy Protects against Enteric Invasion and Lethal Sepsis in a Murine Model of Gastrointestinal Anthrax

    PubMed Central

    Huang, Bruce; Xie, Tao; Rotstein, David; Fang, Hui; Frucht, David M.

    2015-01-01

    The principal portal for anthrax infection in natural animal outbreaks is the digestive tract. Enteric exposure to anthrax, which is difficult to detect or prevent in a timely manner, could be exploited as an act of terror through contamination of human or animal food. Our group has developed a novel animal model of gastrointestinal (GI) anthrax for evaluation of disease pathogenesis and experimental therapeutics, utilizing vegetative Bacillus anthracis (Sterne strain) administered to A/J mice (a complement-deficient strain) by oral gavage. We hypothesized that a humanized recombinant monoclonal antibody (mAb) * that neutralizes the protective antigen (PA) component of B. anthracis lethal toxin (LT) and edema toxin (ET) could be an effective treatment. Although the efficacy of this anti-anthrax PA mAb has been shown in animal models of inhalational anthrax, its activity in GI infection had not yet been ascertained. We hereby demonstrate that passive immunotherapy with anti-anthrax PA mAb, administered at the same time as gastrointestinal exposure to B. anthracis, prevents lethal sepsis in nearly all cases (>90%), while a delay of up to forty-eight hours in treatment still greatly reduces mortality following exposure (65%). Moreover, passive immunotherapy protects against enteric invasion, associated mucosal injury and subsequent dissemination by gastrointestinal B. anthracis, indicating that it acts to prevent the initial stages of infection. * Expired raxibacumab being cycled off the Strategic National Stockpile; biological activity confirmed by in vitro assay. PMID:26426050

  16. Anthrax Lethal Toxin Impairs IL-8 Expression in Epithelial Cells through Inhibition of Histone H3 Modification

    PubMed Central

    Raymond, Benoit; Batsche, Eric; Boutillon, Florence; Wu, Yong-Zheng; Leduc, Dominique; Balloy, Viviane; Raoust, Eloïse; Muchardt, Christian; Goossens, Pierre L.; Touqui, Lhousseine

    2009-01-01

    Lethal toxin (LT) is a critical virulence factor of Bacillus anthracis, the etiological agent of anthrax, whose pulmonary form is fatal in the absence of treatment. Inflammatory response is a key process of host defense against invading pathogens. We report here that intranasal instillation of a B. anthracis strain bearing inactive LT stimulates cytokine production and polymorphonuclear (PMN) neutrophils recruitment in lungs. These responses are repressed by a prior instillation of an LT preparation. In contrast, instillation of a B. anthracis strain expressing active LT represses lung inflammation. The inhibitory effects of LT on cytokine production are also observed in vitro using mouse and human pulmonary epithelial cells. These effects are associated with an alteration of ERK and p38-MAPK phosphorylation, but not JNK phosphorylation. We demonstrate that although NF-κB is essential for IL-8 expression, LT downregulates this expression without interfering with NF-κB activation in epithelial cells. Histone modifications are known to induce chromatin remodelling, thereby enhancing NF-κB binding on promoters of a subset of genes involved in immune response. We show that LT selectively prevents histone H3 phosphorylation at Ser 10 and recruitment of the p65 subunit of NF-κB at the IL-8 and KC promoters. Our results suggest that B. anthracis represses the immune response, in part by altering chromatin accessibility of IL-8 promoter to NF-κB in epithelial cells. This epigenetic reprogramming, in addition to previously reported effects of LT, may represent an efficient strategy used by B. anthracis for invading the host. PMID:19343203

  17. A complex role of anthrax toxin receptor 2 polymorphisms and capillary morphogenesis protein 2 in ankylosing spondylitis pathogenesis.

    PubMed

    Zhang, Zhijian; Yu, Kun; Dai, Dongfa; Yuan, Fang; Liang, Fei; Liu, Nan; Xi, Yongzhi; Sun, Yu-Ying

    2016-09-01

    This study investigated the role of anthrax toxin receptor 2 (ANTXR2) gene polymorphisms and capillary morphogenesis protein 2 (CMG2) expression in susceptibility and pathogenesis to ankylosing spondylitis (AS) in the Han Chinese in Beijing. A case-control study was performed using 602 AS patient samples meeting the revised New York criterion and 619 matched controls from Han Chinese individuals. Nineteen single-nucleotide polymorphisms (SNPs) of ANTXR2 genes were selected and genotyped using the Sequenom iPlex platform. Real-time polymerase chain reaction and flow cytometry were performed to investigate the impact of SNP polymorphisms on ANTXR2 transcription and CMG2 expression, respectively. The association of variants with AS was examined with UNPHASED 3.1.5. A novel association was observed between AS and three SNPs in the ANTXR2 gene (rs4690127, rs6823031, and rs4333130; P = 0.004, 0.011, and 0.013, respectively), confirming the association between rs433130 and AS in the Han Chinese. The strongest haplotype association was observed with rs4690127-rs6823031-rs4333130 (P = 2.5 × 10(-4)). rs6534639 and rs4333130 showed a cis-interaction (P = 0.027) in AS. ANTXR2 messenger RNA (mRNA) expression was significantly higher in the AS group than in the control group (P = 0.039). CMG2 expression in the lipopolysaccharide (LPS)-stimulated group was significantly lower than that in the control group (P = 0.018). This study reports a novel association between ANTXR2 and AS in the Han Chinese. ANTXR2 genetic polymorphisms affect ANTXR2 mRNA transcription and CMG2 expression. The opposing results observed for ANTXR2 transcription and CMG2 expression suggest a complex role of ANTXR2 polymorphisms in AS pathogenesis. PMID:26728147

  18. Induction of cytotoxic T lymphocyte response against Mycobacterial antigen using domain I of anthrax edema factor as antigen delivery system

    SciTech Connect

    Chandra, Subhash; Kaur, Manpreet; Midha, Shuchi; Gorantala, Jyotsna; Bhatnagar, Rakesh . E-mail: rakbhat01@yahoo.com

    2007-05-25

    We have investigated the efficiency of N-terminal 1-260 residues of Edema factor (EFn) as a delivery system for ESAT-6, an antigenic protein of Mycobacterium tuberculosis H{sub 37}R{sub v}, into the cytosol of mammalian cells. The EFn.ESAT-6 recombinant protein was obtained by genetic fusion of EFn and ESAT-6 DNA. Our data shows that in the presence of PA, EFn.ESAT-6 fusion protein is internalized into the cytosol of antigen presenting cells, and the splenocytes produced both Th1 and Th2 cytokines in vitro. Further, EFn.ESAT-6 elicited effective cytotoxicT lymphocyte (CTL) response in an in vitro CTL assay. This study for the first time demonstrates that EFn can be used as a vehicle to deliver heterologous proteins of therapeutic importance.

  19. Anthrax Vaccine

    MedlinePlus

    What is anthrax?Anthrax is a serious disease that can affect both animals and humans. It is caused by bacteria called Bacillus anthracis. People can get anthrax from contact with infected animals, wool, meat, or ...

  20. Susceptibility to anthrax lethal toxin-induced rat death is controlled by a single chromosome 10 locus that includes rNlrp1.

    PubMed

    Newman, Zachary L; Printz, Morton P; Liu, Shihui; Crown, Devorah; Breen, Laura; Miller-Randolph, Sharmina; Flodman, Pamela; Leppla, Stephen H; Moayeri, Mahtab

    2010-05-01

    Anthrax lethal toxin (LT) is a bipartite protease-containing toxin and a key virulence determinant of Bacillus anthracis. In mice, LT causes the rapid lysis of macrophages isolated from certain inbred strains, but the correlation between murine macrophage sensitivity and mouse strain susceptibility to toxin challenge is poor. In rats, LT induces a rapid death in as little as 37 minutes through unknown mechanisms. We used a recombinant inbred (RI) rat panel of 19 strains generated from LT-sensitive and LT-resistant progenitors to map LT sensitivity in rats to a locus on chromosome 10 that includes the inflammasome NOD-like receptor (NLR) sensor, Nlrp1. This gene is the closest rat homolog of mouse Nlrp1b, which was previously shown to control murine macrophage sensitivity to LT. An absolute correlation between in vitro macrophage sensitivity to LT-induced lysis and animal susceptibility to the toxin was found for the 19 RI strains and 12 additional rat strains. Sequencing Nlrp1 from these strains identified five polymorphic alleles. Polymorphisms within the N-terminal 100 amino acids of the Nlrp1 protein were perfectly correlated with LT sensitivity. These data suggest that toxin-mediated lethality in rats as well as macrophage sensitivity in this animal model are controlled by a single locus on chromosome 10 that is likely to be the inflammasome NLR sensor, Nlrp1. PMID:20502689

  1. Development of a comprehensive, validated pharmacophore hypothesis for anthrax toxin lethal factor (LF) inhibitors using genetic algorithms, Pareto scoring, and structural biology.

    PubMed

    Chiu, Ting-Lan; Amin, Elizabeth A

    2012-07-23

    Anthrax is an acute infectious disease caused by the spore-forming bacterium Bacillus anthracis. The anthrax toxin lethal factor (LF), an 89-kDa zinc hydrolase secreted by the bacilli, is the toxin component chiefly responsible for pathogenesis and has been a popular target for rational and structure-based drug design. Although hundreds of small-molecule compounds have been designed to target the LF active site, relatively few reported inhibitors have exhibited activity in cell-based assays, and no LF inhibitor is currently available to treat or prevent anthrax. This study presents a new pharmacophore map assembly, validated by experiment, designed to rapidly identify and prioritize promising LF inhibitor scaffolds from virtual compound libraries. The new hypothesis incorporates structural information from all five available LF enzyme-inhibitor complexes deposited in the Protein Data Bank (PDB) and is the first LF pharmacophore map reported to date that includes features representing interactions involving all three key subsites of the LF catalytic binding region. In a wide-ranging validation study on all 546 compounds for which published LF biological activity data exist, this model displayed strong selectivity toward nanomolar-level LF inhibitors, successfully identifying 72.1% of existing nanomolar-level compounds in an unbiased test set, while rejecting 100% of weakly active (>100 μM) compounds. In addition to its capabilities as a database searching tool, this comprehensive model points to a number of key design principles and previously unidentified ligand-receptor interactions that are likely to influence compound potency. PMID:22697455

  2. Targeting the membrane-anchored serine protease testisin with a novel engineered anthrax toxin prodrug to kill tumor cells and reduce tumor burden

    PubMed Central

    Martin, Erik W.; Buzza, Marguerite S.; Driesbaugh, Kathryn H.; Liu, Shihui; Fortenberry, Yolanda M.; Leppla, Stephen H.; Antalis, Toni M.

    2015-01-01

    The membrane-anchored serine proteases are a unique group of trypsin-like serine proteases that are tethered to the cell surface via transmembrane domains or glycosyl-phosphatidylinositol-anchors. Overexpressed in tumors, with pro-tumorigenic properties, they are attractive targets for protease-activated prodrug-like anti-tumor therapies. Here, we sought to engineer anthrax toxin protective antigen (PrAg), which is proteolytically activated on the cell surface by the proprotein convertase furin to instead be activated by tumor cell-expressed membrane-anchored serine proteases to function as a tumoricidal agent. PrAg's native activation sequence was mutated to a sequence derived from protein C inhibitor (PCI) that can be cleaved by membrane-anchored serine proteases, to generate the mutant protein PrAg-PCIS. PrAg-PCIS was resistant to furin cleavage in vitro, yet cytotoxic to multiple human tumor cell lines when combined with FP59, a chimeric anthrax toxin lethal factor-Pseudomonas exotoxin fusion protein. Molecular analyses showed that PrAg-PCIS can be cleaved in vitro by several serine proteases including the membrane-anchored serine protease testisin, and mediates increased killing of testisin-expressing tumor cells. Treatment with PrAg-PCIS also potently attenuated the growth of testisin-expressing xenograft tumors in mice. The data indicates PrAg can be engineered to target tumor cell-expressed membrane-anchored serine proteases to function as a potent tumoricidal agent. PMID:26392335

  3. Contributions of edema factor and protective antigen to the induction of protective immunity by Bacillus anthracis edema toxin as an intranasal adjuvant.

    PubMed

    Duverger, Alexandra; Carré, Jeanne-Marie; Jee, Junbae; Leppla, Stephen H; Cormet-Boyaka, Estelle; Tang, Wei-Jen; Tomé, Daniel; Boyaka, Prosper N

    2010-11-15

    We have shown that intranasal coapplication of Bacillus anthracis protective Ag (PA) together with a B. anthracis edema factor (EF) mutant having reduced adenylate cyclase activity (i.e., EF-S414N) enhances anti-PA Ab responses, but also acts as a mucosal adjuvant for coadministered unrelated Ags. To elucidate the role of edema toxin (EdTx) components in its adjuvanticity, we examined how a PA mutant lacking the ability to bind EF (PA-U7) or another mutant that allows the cellular uptake of EF, but fails to efficiently mediate its translocation into the cytosol (PA-dFF), would affect EdTx-induced adaptive immunity. Native EdTx promotes costimulatory molecule expression by macrophages and B lymphocytes, and a broad spectrum of cytokine responses by cervical lymph node cells in vitro. These effects were reduced or abrogated when cells were treated with EF plus PA-dFF, or PA-U7 instead of PA. We also intranasally immunized groups of mice with a recombinant fusion protein of Yersinia pestis F1 and LcrV Ags (F1-V) together with EdTx variants consisting of wild-type or mutants PA and EF. Analysis of serum and mucosal Ab responses against F1-V or EdTx components (i.e., PA and EF) revealed no adjuvant activity in mice that received PA-U7 instead of PA. In contrast, coimmunization with PA-dFF enhanced serum Ab responses. Finally, immunization with native PA and an EF mutant lacking adenylate cyclase activity (EF-K346R) failed to enhance Ab responses. In summary, a fully functional PA and a minimum of adenylate cyclase activity are needed for EdTx to act as a mucosal adjuvant. PMID:20952678

  4. Contributions of Edema Factor and Protective Antigen to the Induction of Protective Immunity by Bacillus anthracis Edema Toxin as an Intranasal Adjuvant

    PubMed Central

    Duverger, Alexandra; Carré, Jeanne-Marie; Jee, Junbae; Leppla, Stephen H.; Cormet-Boyaka, Estelle; Tang, Wei-Jen; Tomé, Daniel; Boyaka, Prosper N.

    2013-01-01

    We have shown that intranasal coapplication of Bacillus anthracis protective Ag (PA) together with a B. anthracis edema factor (EF) mutant having reduced adenylate cyclase activity (i.e., EF-S414N) enhances anti-PAAb responses, but also acts as a mucosal adjuvant for coadministered unrelated Ags. To elucidate the role of edema toxin (EdTx) components in its adjuvanticity, we examined how a PA mutant lacking the ability to bind EF (PA-U7) or another mutant that allows the cellular uptake of EF, but fails to efficiently mediate its translocation into the cytosol (PA-dFF), would affect EdTx-induced adaptive immunity. Native EdTx promotes costimulatory molecule expression by macrophages and B lymphocytes, and a broad spectrum of cytokine responses by cervical lymph node cells in vitro. These effects were reduced or abrogated when cells were treated with EF plus PA-dFF, or PA-U7 instead of PA. We also intranasally immunized groups of mice with a recombinant fusion protein of Yersinia pestis F1 and LcrVAgs (F1-V) together with EdTx variants consisting of wild-type or mutants PA and EF. Analysis of serum and mucosal Ab responses against F1-V or EdTx components (i.e., PA and EF) revealed no adjuvant activity in mice that received PA-U7 instead of PA. In contrast, coimmunization with PA-dFF enhanced serum Ab responses. Finally, immunization with native PA and an EF mutant lacking adenylate cyclase activity (EF-K346R) failed to enhance Ab responses. In summary, a fully functional PA and a minimum of adenylate cyclase activity are needed for EdTx to act as a mucosal adjuvant. PMID:20952678

  5. Apoptosis and melanogenesis in human melanoma cells induced by anthrax lethal factor inactivation of mitogen-activated protein kinase kinase

    NASA Astrophysics Data System (ADS)

    Koo, Han-Mo; Vanbrocklin, Matt; McWilliams, Mary Jane; Leppla, Stephan H.; Duesbery, Nicholas S.; Vande Woude, George F.

    2002-03-01

    Lethal factor, the principal virulence factor of Bacillus anthracis, inhibits mitogen-activated protein kinase (MAPK) signaling by proteolytically cleaving MAPK kinases. Edema factor, another component of anthrax toxin, is an adenylate cyclase, which increases intracellular cAMP. Inhibition of MAPK signaling with either anthrax lethal toxin (LeTx) or small molecule MAPK kinase inhibitors triggers apoptosis in human melanoma cells. Normal melanocytes do not undergo apoptosis in response to MAPK inhibition but arrest in the G1 phase of the cell cycle. Importantly, in vivo treatment of human melanoma xenograft tumors in athymic nude mice with LeTx results in significant or complete tumor regression without apparent side effects, suggesting that inhibiting the MAPK signaling pathway may be a useful strategy for treating melanoma. Additionally, interrupting MAPK signaling with LeTx and elevating cAMP with anthrax edema toxin in both melanoma cells and melanocytes lead to dramatic melanin production, perhaps explaining the formation of blackened eschars in cutaneous anthrax.

  6. Novel Yersinia Pestis Toxin that Resembles Bacillus Anthracis Edema Factor: Study of Activity and Structural Modeling

    SciTech Connect

    Motin, V; Garcia, E; Barsky, D; Zemla, A

    2003-02-05

    The goal of this project was to begin both experimental and computational studies of the novel plague toxin to establish its biological properties and create its 3D-model. The project was divided into two parts. (1) Experimental--This part was devoted to determine distribution of the genes encoding novel plague toxin among different isolates of Y.pestis. If the EF-like activity is important for Y.pestis pathogenicity, it is anticipated that all highly virulent strains will contain the toxin genes. Also, they proposed to initiate research to investigate the functionality of the novel Y.pestis toxin that they hypothesize is likely to significantly contribute to the virulence of this dangerous microbe. this research design consisted of amplification, cloning and expression in E.coli the toxin genes followed by affinity purification of the recombinant protein that can be further used for testing of enzymatic activity. (2) Computational--The structural modeling of the putative EF of Y.pestis was based on multiple sequence alignments, secondary structure predictions, and comparison with 3D models of the EF of B. anthracis. The x-ray structure of the last has been recently published [Nature. 2002. 415(Jan):396-402]. The final model was selected after detailed analysis to determine if the structure is consistent with the biological function.

  7. Bacillus anthracis Lethal Toxin Reduces Human Alveolar Epithelial Barrier Function

    PubMed Central

    Langer, Marybeth; Duggan, Elizabeth Stewart; Booth, John Leland; Patel, Vineet Indrajit; Zander, Ryan A.; Silasi-Mansat, Robert; Ramani, Vijay; Veres, Tibor Zoltan; Prenzler, Frauke; Sewald, Katherina; Williams, Daniel M.; Coggeshall, Kenneth Mark; Awasthi, Shanjana; Lupu, Florea; Burian, Dennis; Ballard, Jimmy Dale; Braun, Armin

    2012-01-01

    The lung is the site of entry for Bacillus anthracis in inhalation anthrax, the deadliest form of the disease. Bacillus anthracis produces virulence toxins required for disease. Alveolar macrophages were considered the primary target of the Bacillus anthracis virulence factor lethal toxin because lethal toxin inhibits mouse macrophages through cleavage of MEK signaling pathway components, but we have reported that human alveolar macrophages are not a target of lethal toxin. Our current results suggest that, unlike human alveolar macrophages, the cells lining the respiratory units of the lung, alveolar epithelial cells, are a target of lethal toxin in humans. Alveolar epithelial cells expressed lethal toxin receptor protein, bound the protective antigen component of lethal toxin, and were subject to lethal-toxin-induced cleavage of multiple MEKs. These findings suggest that human alveolar epithelial cells are a target of Bacillus anthracis lethal toxin. Further, no reduction in alveolar epithelial cell viability was observed, but lethal toxin caused actin rearrangement and impaired desmosome formation, consistent with impaired barrier function as well as reduced surfactant production. Therefore, by compromising epithelial barrier function, lethal toxin may play a role in the pathogenesis of inhalation anthrax by facilitating the dissemination of Bacillus anthracis from the lung in early disease and promoting edema in late stages of the illness. PMID:23027535

  8. Anthrax: Symptoms

    MedlinePlus

    ... hands Inhalation anthrax symptoms can include: Fever and chills Chest Discomfort Shortness of breath Confusion or dizziness ... aches Gastrointestinal anthrax symptoms can include: Fever and chills Swelling of neck or neck glands Sore throat ...

  9. Anthrax Susceptibility: Human Genetic Polymorphisms Modulating ANTXR2 Expression

    PubMed Central

    Zhang, Zhang; Zhang, Yan; Shi, Minglei; Ye, Bingyu; Shen, Wenlong; Li, Ping; Xing, Lingyue; Zhang, Xiaopeng; Hou, Lihua; Xu, Junjie; Zhao, Zhihu; Chen, Wei

    2015-01-01

    Anthrax toxin causes anthrax pathogenesis and expression levels of ANTXR2 (anthrax toxin receptor 2) are strongly correlated with anthrax toxin susceptibility. Previous studies found that ANTXR2 transcript abundance varies considerably in individuals of different ethnic/geographical groups, but no eQTLs (expression quantitative trait loci) have been identified. By using 3C (chromatin conformation capture), CRISPR-mediated genomic deletion and dual-luciferase reporter assay, gene loci containing cis-regulatory elements of ANTXR2 were localized. Two SNPs (single nucleotide polymorphism) at the conserved CREB-binding motif, rs13140055 and rs80314910 in the promoter region of the gene, modulating ANTXR2 promoter activity were identified. Combining these two regulatory SNPs with a previously reported SNP, rs12647691, for the first time, a statistically significant correlation between human genetic variations and anthrax toxin sensitivity was observed. These findings further our understanding of human variability in ANTXR2 expression and anthrax toxin susceptibility. PMID:26703731

  10. Anthrax Susceptibility: Human Genetic Polymorphisms Modulating ANTXR2 Expression.

    PubMed

    Zhang, Zhang; Zhang, Yan; Shi, Minglei; Ye, Bingyu; Shen, Wenlong; Li, Ping; Xing, Lingyue; Zhang, Xiaopeng; Hou, Lihua; Xu, Junjie; Zhao, Zhihu; Chen, Wei

    2016-01-01

    Anthrax toxin causes anthrax pathogenesis and expression levels of ANTXR2 (anthrax toxin receptor 2) are strongly correlated with anthrax toxin susceptibility. Previous studies found that ANTXR2 transcript abundance varies considerably in individuals of different ethnic/geographical groups, but no eQTLs (expression quantitative trait loci) have been identified. By using 3C (chromatin conformation capture), CRISPR-mediated genomic deletion and dual-luciferase reporter assay, gene loci containing cis-regulatory elements of ANTXR2 were localized. Two SNPs (single nucleotide polymorphism) at the conserved CREB-binding motif, rs13140055 and rs80314910 in the promoter region of the gene, modulating ANTXR2 promoter activity were identified. Combining these two regulatory SNPs with a previously reported SNP, rs12647691, for the first time, a statistically significant correlation between human genetic variations and anthrax toxin sensitivity was observed. These findings further our understanding of human variability in ANTXR2 expression and anthrax toxin susceptibility. PMID:26703731

  11. Electrochemical immunosensor based on bismuth nanocomposite film and cadmium ions functionalized titanium phosphates for the detection of anthrax protective antigen toxin.

    PubMed

    Sharma, Mukesh K; Narayanan, J; Upadhyay, Sanjay; Goel, Ajay K

    2015-12-15

    Bacillus anthracis is a bioterrorism agent classified by the Centers for Disease Control and Prevention (CDC). Herein, a novel electrochemical immunosensor for the sensitive, specific and easy detection of anthrax protective antigen (PA) toxin in picogram concentration was developed. The immunosensor consists of (i) a Nafion-multiwall carbon nanotubes-bismuth nanocomposite film modified glassy carbon electrodes (BiNPs/Nafion-MWCNTs/GCE) as a sensing platform and (ii) titanium phosphate nanoparticles-cadmium ion-mouse anti-PA antibodies (TiP-Cd(2+)-MαPA antibodies) as signal amplification tags. Scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), thermogravimmetric analysis (TGA), Fourier transform-infra red spectroscopy (FT-IR), zeta-potential analysis, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were employed to characterize the synthesized TiP nanoparticles and modified electrode surfaces. The immunosensing performance of BiNPs/Nafion-MWCNTs/GCE was evaluated based on sandwich immunoassay protocol. A square wave voltammetry (SWV) scan from -1.2 to -0.3 V in HAc-NaAc buffer solution (pH 4.6) without stripping process was performed to record the electrochemical responses at -0.75 V corresponding to high content of Cd(2+) ions loaded in TiP nanoparticles for the measurement of PA toxin. Under optimal conditions, the currents increased with increasing PA toxin concentrations in spiked human serum samples and showed a linear range from 0.1 ng/ml to 100 ng/ml. The limit of detection of developed immunosensor was found to be 50 pg/ml at S/N=3. The total time of analysis was 35 min. PMID:26148674

  12. Neutralizing Monoclonal Antibodies Directed against Defined Linear Epitopes on Domain 4 of Anthrax Protective Antigen▿

    PubMed Central

    Kelly-Cirino, Cassandra D.; Mantis, Nicholas J.

    2009-01-01

    The anthrax protective antigen (PA) is the receptor-binding subunit common to lethal toxin (LT) and edema toxin (ET), which are responsible for the high mortality rates associated with inhalational Bacillus anthracis infection. Although recombinant PA (rPA) is likely to be an important constituent of any future anthrax vaccine, evaluation of the efficacies of the various candidate rPA vaccines is currently difficult, because the specific B-cell epitopes involved in toxin neutralization have not been completely defined. In this study, we describe the identification and characterization of two murine monoclonal immunoglobulin G1 antibodies (MAbs), 1-F1 and 2-B12, which recognize distinct linear neutralizing epitopes on domain 4 of PA. 1-F1 recognized a 12-mer peptide corresponding to residues 692 to 703; this epitope maps to a region of domain 4 known to interact with the anthrax toxin receptor CMG-2 and within a conformation-dependent epitope recognized by the well-characterized neutralizing MAb 14B7. As expected, 1-F1 blocked PA's ability to associate with CMG-2 in an in vitro solid-phase binding assay, and it protected murine macrophage cells from intoxication with LT. 2-B12 recognized a 12-mer peptide corresponding to residues 716 to 727, an epitope located immediately adjacent to the core 14B7 binding site and a stretch of amino acids not previously identified as a target of neutralizing antibodies. 2-B12 was as effective as 1-F1 in neutralizing LT in vitro, although it only partially inhibited PA binding to its receptor. Mice passively administered 1-F1 or 2-B12 were partially protected against a lethal challenge with LT. These results advance our fundamental understanding of the mechanisms by which antibodies neutralize anthrax toxin and may have future application in the evaluation of candidate rPA vaccines. PMID:19703971

  13. Primary Involvement of Pharynx and Peyer's Patch in Inhalational and Intestinal Anthrax

    PubMed Central

    Glomski, Ian J; Piris-Gimenez, Alejandro; Huerre, Michel; Mock, Michèle; Goossens, Pierre L

    2007-01-01

    Bacillus anthracis causes three forms of anthrax: inhalational, gastrointestinal, and cutaneous. Anthrax is characterized by both toxemia, which is caused by secretion of immunomodulating toxins (lethal toxin and edema toxin), and septicemia, which is associated with bacterial encapsulation. Here we report that, contrary to the current view of B. anthracis pathogenesis, B. anthracis spores germinate and establish infections at the initial site of inoculation in both inhalational and cutaneous infections without needing to be transported to draining lymph nodes, and that inhaled spores establish initial infection in nasal-associated lymphoid tissues. Furthermore, we found that Peyer's patches in the mouse intestine are the primary site of bacterial growth after intragastric inoculation, thus establishing an animal model of gastrointestinal anthrax. All routes of infection progressed to the draining lymph nodes, spleen, lungs, and ultimately the blood. These discoveries were made possible through the development of a novel dynamic mouse model of B. anthracis infection using bioluminescent non-toxinogenic capsulated bacteria that can be visualized within the mouse in real-time, and demonstrate the value of in vivo imaging in the analysis of B. anthracis infection. Our data imply that previously unrecognized portals of bacterial entry demand more intensive investigation, and will significantly transform the current perception of inhalational, gastrointestinal, and cutaneous B. anthracis pathogenesis. PMID:17542645

  14. Targeting the MAP kinase pathway in astrocytoma cells using a recombinant anthrax lethal toxin as a way to inhibit cell motility and invasion.

    PubMed

    Al-Dimassi, Saleh; Salloum, Gilbert; Saykali, Bechara; Khoury, Oula; Liu, Shihui; Leppla, Stephen H; Abi-Habib, Ralph; El-Sibai, Mirvat

    2016-05-01

    Malignant astrocytomas are highly invasive into adjacent and distant regions of the normal brain. Understanding and targeting cancer cell invasion is an important therapeutic approach. Cell invasion is a complex process that replies on many signaling pathways including the mitogen-activated protein (MAP) kinase (MAPK). In many cell lines, the use of MAPK-targeted drugs proved to be a potential method to inhibit cancer cell motility. In the present study, we use a recombinant anthrax lethal toxin (LeTx), which selectively inhibits the MAPK pathway, in order to target invasion. LeTx proved ineffective on cell survival in astrocytoma (as well as normal cells). However, astrocytoma cells that were treated with LeTx showed a significant decrease in cell motility as seen by wound healing as well as random 2D motility in serum. The cells also showed a decrease in invasion across a collagen matrix. The effect of LeTx on cell migration was mediated though the deregulation of Rho GTPases, which play a role in cell motility. Finally, the effect of LeTx on cell migration and Rho GTPases was mimicked by the inhibition of the MAPK pathway. In this study, we describe for the first time the effect of the LeTx on cancer cell motility and invasion not cell survival making it a potentially selective brain tumor invasion inhibitor. PMID:26984023

  15. Adenoviral Expression of a Bispecific VHH-Based Neutralizing Agent That Targets Protective Antigen Provides Prophylactic Protection from Anthrax in Mice.

    PubMed

    Moayeri, Mahtab; Tremblay, Jacqueline M; Debatis, Michelle; Dmitriev, Igor P; Kashentseva, Elena A; Yeh, Anthony J; Cheung, Gordon Y C; Curiel, David T; Leppla, Stephen; Shoemaker, Charles B

    2016-03-01

    Bacillus anthracis, the causative agent of anthrax, secretes three polypeptides, which form the bipartite lethal and edema toxins (LT and ET, respectively). The common component in these toxins, protective antigen (PA), is responsible for binding to cellular receptors and translocating the lethal factor (LF) and edema factor (EF) enzymatic moieties to the cytosol. Antibodies against PA protect against anthrax. We previously isolated toxin-neutralizing variable domains of camelid heavy-chain-only antibodies (VHHs) and demonstrated their in vivo efficacy. In this work, gene therapy with an adenoviral (Ad) vector (Ad/VNA2-PA) (VNA, VHH-based neutralizing agents) promoting the expression of a bispecific VHH-based neutralizing agent (VNA2-PA), consisting of two linked VHHs targeting different PA-neutralizing epitopes, was tested in two inbred mouse strains, BALB/cJ and C57BL/6J, and found to protect mice against anthrax toxin challenge and anthrax spore infection. Two weeks after a single treatment with Ad/VNA2-PA, serum VNA2-PA levels remained above 1 μg/ml, with some as high as 10 mg/ml. The levels were 10- to 100-fold higher and persisted longer in C57BL/6J than in BALB/cJ mice. Mice were challenged with a lethal dose of LT or spores at various times after Ad/VNA2-PA administration. The majority of BALB/cJ mice having serum VNA2-PA levels of >0.1 μg/ml survived LT challenge, and 9 of 10 C57BL/6J mice with serum levels of >1 μg/ml survived spore challenge. Our findings demonstrate the potential for genetic delivery of VNAs as an effective method for providing prophylactic protection from anthrax. We also extend prior findings of mouse strain-based differences in transgene expression and persistence by adenoviral vectors. PMID:26740390

  16. Anthrax Basics

    MedlinePlus

    ... it like the cold or flu. How do animals get infected with anthrax? Domestic and wild animals such as cattle, sheep, goats, antelope, and deer ... soil, plants, or water. In areas where domestic animals have had anthrax in the past, routine vaccination ...

  17. Cutaneous anthrax (image)

    MedlinePlus

    Anthrax is caused by the bacteria Bacillus anthracis . While anthrax commonly affects hoofed animals such as sheep and goats, humans may get sick from anthrax, too. The most common type of anthrax infection ...

  18. The anthrax protective antigen (PA63) bound conformation of a peptide inhibitor of the binding of lethal factor to PA63: as determined by trNOESY NMR and molecular modeling.

    PubMed

    Hicks, Rickey P; Bhattacharjee, Apurba K; Koser, Brandon W; Traficante, Daniel D

    2004-10-21

    Anthrax protective antigen (PA) is one of the three proteins produced by the gram positive bacteria Bacillus anthracis collectively known as the "anthrax toxin" (Ascenzi, P.; Visca, P.; Ippolito, G.; Spallarossa, A.; Bolognesi, M.; et al. Anthrax toxin: a tripartite lethal combination. FEBS Lett. 2002, 531, 384-388). The role played by PA in anthrax intoxication is to transport the two enzymes lethal factor (LF) and edema factor (EF) into the cell. Collier and co-workers (Mourez, M.; Kane, R. S.; Mogridge, J.; Metallo, S.; Deschatelets, P.; et al. Designing a polyvalent inhibitor of anthrax toxin. Nat. Biotechnol. 2001, 958). reported the isolation of two peptides via phage display that bind to the PA63 heptamer and inhibit its interaction with LF and EF, and thereby prevent the transport of LF and EF into the cell. One of these peptides, His-Thr-Ser-Thr-Try-Trp-Trp-Leu-Asp-Gly-Ala-Pro (P1), was selected for structural investigation on the basis of its ability to prevent the binding of LF to the PA63 heptamer bundle. Two-dimensional trNOESY experiments coupled with NOE restrained simulated annealing calculations were used to determine the PA63-bound conformation of P1. On binding to PA63, P1 adopts a helical conformation involving residues 3-9 while the C- and N-terminal residues exhibit dynamic fraying. PMID:15481973

  19. Sequence and organization of pXO1, the large Bacillus anthracis plasmid harboring the anthrax toxin genes.

    PubMed

    Okinaka, R T; Cloud, K; Hampton, O; Hoffmaster, A R; Hill, K K; Keim, P; Koehler, T M; Lamke, G; Kumano, S; Mahillon, J; Manter, D; Martinez, Y; Ricke, D; Svensson, R; Jackson, P J

    1999-10-01

    The Bacillus anthracis Sterne plasmid pXO1 was sequenced by random, "shotgun" cloning. A circular sequence of 181,654 bp was generated. One hundred forty-three open reading frames (ORFs) were predicted using GeneMark and GeneMark.hmm, comprising only 61% (110,817 bp) of the pXO1 DNA sequence. The overall guanine-plus-cytosine content of the plasmid is 32.5%. The most recognizable feature of the plasmid is a "pathogenicity island," defined by a 44.8-kb region that is bordered by inverted IS1627 elements at each end. This region contains the three toxin genes (cya, lef, and pagA), regulatory elements controlling the toxin genes, three germination response genes, and 19 additional ORFs. Nearly 70% of the ORFs on pXO1 do not have significant similarity to sequences available in open databases. Absent from the pXO1 sequence are homologs to genes that are typically required to drive theta replication and to maintain stability of large plasmids in Bacillus spp. Among the ORFs with a high degree of similarity to known sequences are a collection of putative transposases, resolvases, and integrases, suggesting an evolution involving lateral movement of DNA among species. Among the remaining ORFs, there are three sequences that may encode enzymes responsible for the synthesis of a polysaccharide capsule usually associated with serotype-specific virulent streptococci. PMID:10515943

  20. STRUCTURE BASED DESIGN OF PROTEIN LIGANDS: A STUDY OF ANTIBODY-LIKE SCAFFOLDS TARGETED AGAINST THE ANTHRAX TOXIN

    SciTech Connect

    P. SHIFLETT; E. HONG-GELLER; ET AL

    2000-12-01

    We have adopted structure-based approaches to enhance the affinities of two single chain antibodies, scFv1 and scFv4, that bind to two different epitopes on the Protective Antigen (PA), a toxin from Bacillus anthracis. In one approach, we have modified scFv4 and re-engineered a novel antibody-like scaffold in which we have placed V{sub L} on the N terminus and V{sub H} on the C-terminus and joined them by a 10 amino-acid-long linker. This scaffold preserves the native V{sub L}-V{sub H} contact interface and the dispositions of the CDR loops. It binds to PA with 10 fold higher affinity than scFv4. In a second approach, we have created a bispecific ligand by covalently joining scFv1 and scFv4 by a flexible linker that supports simultaneous and synergistic binding of the two scFvs to PA. This bispecific scFv1-linker-scFv4 binds to PA with 10 fold higher affinity than the individual scFvs. The newly re-engineered antibody-like scaffold of scFv4 and scFv1-linker-scFv4 are expected to be potent inhibitors of PA binding to the host cells.

  1. Anthrax lethal toxin down-regulates type-IIA secreted phospholipase A(2) expression through MAPK/NF-kappaB inactivation.

    PubMed

    Raymond, Benoit; Ravaux, Lucas; Mémet, Sylvie; Wu, YongZheng; Sturny-Leclère, Aude; Leduc, Dominique; Denoyelle, Chantal; Goossens, Pierre L; Payá, Miguel; Raymondjean, Michel; Touqui, Lhousseine

    2010-04-15

    Bacillus anthracis, the etiological agent of anthrax, produces lethal toxin (LT) that displays a metallo-proteolytic activity toward the N-terminus of the MAPK-kinases. We have previously shown that secreted type-IIA phospholipase A(2) (sPLA(2)-IIA) exhibits potent anthracidal activity. In vitro expression of sPLA(2)-IIA in guinea pig alveolar macrophages (AMs), the major source of this enzyme in lung tissues, is inhibited by LT. Here, we examined the mechanisms involved in sPLA(2)-IIA inhibition by LT. We first showed that chemical inhibitors of p38 and ERK MAPKs reduced sPLA(2)-IIA expression in AMs indicating that these kinases play a role in sPLA(2)-IIA expression. LT inhibited IL-1beta-induced p38 phosphorylation as well as sPLA(2)-IIA promoter activity in CHO cells. Inhibition of sPLA(2)-IIA promoter activity was mimicked by co-transfection with dominant negative construct of p38 (DN-p38) and reversed by the active form of p38-MAPK (AC-p38). Both LT and DN-p38 decreased IL-1beta-induced NF-kappaB luciferase activity. This contrasted with the effect of AC-p38, which enhanced this activity. However, neither LT nor specific p-38 inhibitor interfered with LPS-induced IkappaBalpha degradation or NF-kappaB nuclear translocation in AMs. Subcutaneous administration of LT to guinea pig before LPS challenge reduced sPLA(2)-IIA levels in broncho-alveolar lavages and ears. We conclude that sPLA(2)-IIA expression is induced via a sequential MAPK-NF-kappaB activation and that LT inhibits this expression likely by interfering with the transactivation of NF-kappaB in the nucleus. This inhibition, which is operating both in vitro and in vivo, may represent a mechanism by which B. anthracis subvert host defense. PMID:19962969

  2. Anthrax Vaccine

    MedlinePlus

    ... products some military personnel, as determined by the Department of Defense These people should get five doses of vaccine ( ... cdc.gov/agent/anthrax/vaccination/. Contact the U.S Department of Defense (DoD): call 1-877-438-8222 or visit ...

  3. Anthrax blood test

    MedlinePlus

    Anthrax serology test; Antibody test for anthrax; Serologic test for B anthracis ... A normal result means no antibodies to the anthrax bacteria were seen in your blood sample. However, during the early stages of infection, your body may only ...

  4. On the role of macrophages in anthrax.

    PubMed Central

    Hanna, P C; Acosta, D; Collier, R J

    1993-01-01

    Bacillus anthracis, the causative agent of anthrax, produces systemic shock and death in susceptible animals, primarily through the action of its lethal toxin. This toxin, at high concentrations, induces lysis of macrophages in vitro but shows little or no effect on other cells. We found that when mice were specifically depleted of macrophages by silica injections, they became resistant to the toxin. Sensitivity could be restored by coinjection of toxin-sensitive cultured macrophages (RAW 264.7 cells) but not by coinjection of other cell lines tested. These results implied that macrophages mediate the action of lethal toxin in vivo and led us to investigate their role in death of the mammalian host. Sublytic concentrations of lethal toxin, orders of magnitude lower than those required to induce lysis of RAW 264.7 cells, were found to induce these cells to express interleukin 1 (IL-1) and tumor necrosis factor in vitro. Passive immunization against IL-1 or injection of an IL-1 receptor antagonist protected mice from toxin challenge, whereas anti-tumor necrosis factor provided little, if any, protection. These results imply that systemic shock and death from anthrax result primarily from the effects of high levels of cytokines, principally IL-1, produced by macrophages that have been stimulated by the anthrax lethal toxin. PMID:8234277

  5. Soluble expression and purification of the anthrax protective antigen in E. coli and identification of a novel dominant-negative mutant N435C.

    PubMed

    Wu, Gaobing; Feng, Chunfang; Hong, Yuzhi; Guo, Aizhen; Cao, Sha; Dong, Junli; Lin, Ling; Liu, Ziduo

    2010-06-01

    The anthrax toxin is an AB-type bacterium toxin composed of the protective antigen (PA) as the cell-binding B component, and the lethal factor (LF) and edema toxin (EF) as the catalytic A components. The PA component is a key factor in anthrax-related research and recombinant PA can be produced in general in Escherichia coli. However, such recombinant PA always forms inclusion bodies in the cytoplasm of E. coli, making difficult the procedure of its purification. In this study, we found that the solubility of recombinant PA was dramatically enhanced by fusion with glutathione S-transferase (GST) and an induction of its expression at 28 degrees C. The PA was purified to high homogeneity and a yield of 3 mg protein was obtained from 1 l culture by an affinity-chromatography approach. Moreover, we expressed and purified three PA mutants, I394C, A396C, and N435C, which were impaired in expression in previous study. Among them, a novel mutant N435C which conferred dominant-negative inhibitory activity on PA was identified. This new mutant may be useful in designing new antitoxin for anthrax prophylaxis and therapy. PMID:20213183

  6. Phospho-MEK1/2 and uPAR Expression Determine Sensitivity of AML Blasts to a Urokinase-Activated Anthrax Lethal Toxin (PrAgU2/LF)1

    PubMed Central

    Bekdash, Amira; Darwish, Manal; Timsah, Zahra; Kassab, Elias; Ghanem, Hadi; Najjar, Vicky; Ghosn, Marwan; Nasser, Selim; El-Hajj, Hiba; Bazerbachi, Ali; Liu, Shihui; Leppla, Stephen H.; Frankel, Arthur E.; Abi-Habib, Ralph J.

    2015-01-01

    In this study, we attempt to target both the urokinase plasminogen activator and the mitogen-activated protein kinase pathway in acute myeloid leukemia (AML) cell lines and primary AML blasts using PrAgU2/LF, a urokinase-activated anthrax lethal toxin. PrAgU2/LF was cytotoxic to five out of nine AML cell lines. Cytotoxicity of PrAgU2/LF appeared to be nonapoptotic and was associated with MAPK activation and urokinase activity because all the PrAgU2/LF-sensitive cell lines showed both uPAR expression and high levels of MEK1/2 phosphorylation. Inhibition of uPAR or desensitization of cells to MEK1/2 inhibition blocked toxicity of PrAgU2/LF, indicating requirement for both uPAR expression and MAPK activation for activity. PrAgU2/LF was also cytotoxic to primary blasts from AML patients, with blasts from four out of five patients showing a cytotoxic response to PrAgU2/LF. Cytotoxicity of primary AML blasts was also dependent on uPAR expression and phos-MEK1/2 levels. CD34+ bone marrow blasts and peripheral blood mononuclear cells lacked uPAR expression and were resistant to PrAgU2/LF, demonstrating the lack of toxicity to normal hematological cells and, therefore, the tumor selectivity of this approach. Dose escalation in mice revealed that the maximal tolerated dose of PrAgU2/LF is at least 5.7-fold higher than that of the wild-type anthrax lethal toxin, PrAg/LF, further demonstrating the increased safety of this molecule. We have shown, in this study, that PrAgU2/LF is a novel, dual-specific molecule for the selective targeting of AML. PMID:26500025

  7. Raxibacumab: potential role in the treatment of inhalational anthrax

    PubMed Central

    Kummerfeldt, Carlos E

    2014-01-01

    Anthrax is a highly contagious and potentially fatal human disease caused by Bacillus anthracis, an aerobic, Gram-positive, spore-forming rod-shaped bacterium with worldwide distribution as a zoonotic infection in herbivore animals. Bioterrorist attacks with inhalational anthrax have prompted the development of more effective treatments. Antibodies against anthrax toxin have been shown to decrease mortality in animal studies. Raxibacumab is a recombinant human monoclonal antibody developed against inhalational anthrax. The drug received approval after human studies showed its safety and animal studies demonstrated its efficacy for treatment as well as prophylaxis against inhalational anthrax. It works by preventing binding of the protective antigen component of the anthrax toxin to its receptors in host cells, thereby blocking the toxin’s deleterious effects. Recently updated therapy guidelines for Bacillus anthracis recommend the use of antitoxin treatment. Raxibacumab is the first monoclonal antitoxin antibody made available that can be used with the antibiotics recommended for treatment of the disease. When exposure is suspected, raxibacumab should be given with anthrax vaccination to augment immunity. Raxibacumab provides additional protection against inhalational anthrax via a mechanism different from that of either antibiotics or active immunization. In combination with currently available and recommended therapies, raxibacumab should reduce the morbidity and mortality of inhalational anthrax. PMID:24812521

  8. A Comparison of the Adaptive Immune Response between Recovered Anthrax Patients and Individuals Receiving Three Different Anthrax Vaccines.

    PubMed

    Laws, Thomas R; Kuchuloria, Tinatin; Chitadze, Nazibriola; Little, Stephen F; Webster, Wendy M; Debes, Amanda K; Saginadze, Salome; Tsertsvadze, Nikoloz; Chubinidze, Mariam; Rivard, Robert G; Tsanava, Shota; Dyson, Edward H; Simpson, Andrew J H; Hepburn, Matthew J; Trapaidze, Nino

    2016-01-01

    Several different human vaccines are available to protect against anthrax. We compared the human adaptive immune responses generated by three different anthrax vaccines or by previous exposure to cutaneous anthrax. Adaptive immunity was measured by ELISPOT to count cells that produce interferon (IFN)-γ in response to restimulation ex vivo with the anthrax toxin components PA, LF and EF and by measuring circulating IgG specific to these antigens. Neutralising activity of antisera against anthrax toxin was also assayed. We found that the different exposures to anthrax antigens promoted varying immune responses. Cutaneous anthrax promoted strong IFN-γ responses to all three antigens and antibody responses to PA and LF. The American AVA and Russian LAAV vaccines induced antibody responses to PA only. The British AVP vaccine produced IFN-γ responses to EF and antibody responses to all three antigens. Anti-PA (in AVA and LAAV vaccinees) or anti-LF (in AVP vaccinees) antibody titres correlated with toxin neutralisation activities. Our study is the first to compare all three vaccines in humans and show the diversity of responses against anthrax antigens. PMID:27007118

  9. A Comparison of the Adaptive Immune Response between Recovered Anthrax Patients and Individuals Receiving Three Different Anthrax Vaccines

    PubMed Central

    Laws, Thomas R.; Kuchuloria, Tinatin; Chitadze, Nazibriola; Little, Stephen F.; Webster, Wendy M.; Debes, Amanda K.; Saginadze, Salome; Tsertsvadze, Nikoloz; Chubinidze, Mariam; Rivard, Robert G.; Tsanava, Shota; Dyson, Edward H.; Simpson, Andrew J. H.; Hepburn, Matthew J.; Trapaidze, Nino

    2016-01-01

    Several different human vaccines are available to protect against anthrax. We compared the human adaptive immune responses generated by three different anthrax vaccines or by previous exposure to cutaneous anthrax. Adaptive immunity was measured by ELISPOT to count cells that produce interferon (IFN)-γ in response to restimulation ex vivo with the anthrax toxin components PA, LF and EF and by measuring circulating IgG specific to these antigens. Neutralising activity of antisera against anthrax toxin was also assayed. We found that the different exposures to anthrax antigens promoted varying immune responses. Cutaneous anthrax promoted strong IFN-γ responses to all three antigens and antibody responses to PA and LF. The American AVA and Russian LAAV vaccines induced antibody responses to PA only. The British AVP vaccine produced IFN-γ responses to EF and antibody responses to all three antigens. Anti-PA (in AVA and LAAV vaccinees) or anti-LF (in AVP vaccinees) antibody titres correlated with toxin neutralisation activities. Our study is the first to compare all three vaccines in humans and show the diversity of responses against anthrax antigens. PMID:27007118

  10. GRP78(BiP) facilitates the cytosolic delivery of anthrax lethal factor (LF) in vivo and functions as an unfoldase in vitro

    PubMed Central

    Tamayo, Alfred G.; Slater, Louise; Taylor-Parker, Julian; Bharti, Ajit; Harrison, Robert; Hung, Deborah T.; Murphy, John R.

    2011-01-01

    Summary Anthrax toxin is an A/B bacterial protein toxin which is composed of the enzymatically active Lethal Factor (LF) and/or Oedema Factor (EF) bound to Protective Antigen 63 (PA63) which functions as both the receptor binding and transmembrane domains. Once the toxin binds to its cell surface receptors it is internalized into the cell and traffics through Rab5- and Rab7-associated endosomal vesicles. Following acidification of the vesicle lumen, PA63 undergoes a dynamic change forming a beta-barrel that inserts into and forms a pore through the endosomal membrane. It is widely recognized that LF, and the related fusion protein LFnDTA, must be completely denatured in order to transit through the PA63 formed pore and enter the eukaryotic cell cytosol. We demonstrate by protease protection assays that the molecular chaperone GRP78 mediates the unfolding of LFnDTA and LF at neutral pH and thereby converts these proteins from a trypsin resistant to sensitive conformation. We have used immuno-electron microscopy and gold-labeled antibodies to demonstrate that both GRP78 and GRP94 chaperones are present in the lumen of endosomal vesicles. Finally, we have used siRNA to demonstrate that knock down of GRP78 results in the emergence of resistance to anthrax lethal toxin and edema toxin action. PMID:21797942

  11. Indigenous human cutaneous anthrax in Texas.

    PubMed

    Taylor, J P; Dimmitt, D C; Ezzell, J W; Whitford, H

    1993-01-01

    In December 1988 an indigenous case of cutaneous anthrax was identified in Texas. The patient, a 63-year-old male Hispanic from southwest Texas, was a sheep shearer and had a recent history of dissecting sheep that had died suddenly. He experienced an illness characterized by left arm pain and edema. A necrotic lesion developed on his left forearm, with cellulitis and lymphadenopathy. After treatment with oral and intravenous penicillins, the patient fully recovered. Western blot testing revealed a fourfold or greater rise in antibody titer to Bacillus anthracis protective antigen and lethal factor. This represents the first case of indigenous anthrax in Texas in more than 20 years. PMID:8420007

  12. Nitric oxide production contributes to Bacillus anthracis edema toxin-associated arterial hypotension and lethality: ex vivo and in vivo studies in the rat.

    PubMed

    Li, Yan; Cui, Xizhong; Xu, Wanying; Ohanjanian, Lernik; Sampath-Kumar, Hanish; Suffredini, Dante; Moayeri, Mahtab; Leppla, Stephen; Fitz, Yvonne; Eichacker, Peter Q

    2016-09-01

    We showed previously that Bacillus anthracis edema toxin (ET), comprised of protective antigen (PA) and edema factor (EF), inhibits phenylephrine (PE)-induced contraction in rat aortic rings and these effects are diminished in endothelial-denuded rings. Therefore, employing rat aortic ring and in vivo models, we tested the hypothesis that nitric oxide (NO) contributes to ET's arterial effects. Compared with rings challenged with PA alone, ET (PA + EF) reduced PE-stimulated maximal contractile force (MCF) and increased the PE concentration producing 50% MCF (EC50) (P < 0.0001). Compared with placebo, l-nitro-arginine methyl-ester (l-NAME), an NO synthase (NOS) inhibitor, reduced ET's effects on MCF and EC50 in patterns that approached or were significant (P = 0.06 and 0.03, respectively). In animals challenged with 24-h ET infusions, l-NAME (0.5 or 1.0 mg·kg(-1)·h(-1)) coadministration increased survival to 17 of 28 animals (60.7%) compared with 4 of 27 (14.8%) given placebo (P = 0.01). Animals receiving l-NAME but no ET all survived. Compared with PBS challenge, ET increased NO levels at 24 h and l-NAME decreased these increases (P < 0.0001). ET infusion decreased mean arterial blood pressure (MAP) in placebo and l-NAME-treated animals (P < 0.0001) but l-NAME reduced decreases in MAP with ET from 9 to 24 h (P = 0.03 for the time interaction). S-methyl-l-thiocitrulline, a selective neuronal NOS inhibitor, had effects in rings and, at a high dose in vivo models, comparable to l-NAME, whereas N'-[3-(aminomethyl)benzyl]-acetimidamide, a selective inducible NOS inhibitor, did not. NO production contributes to ET's arterial relaxant, hypotensive, and lethal effects in the rat. PMID:27448553

  13. Inhibitors of the Metalloproteinase Anthrax Lethal Factor.

    PubMed

    Goldberg, Allison B; Turk, Benjamin E

    2016-01-01

    Bacillus anthracis, a rod shaped, spore forming, gram positive bacteria, is the etiological agent of anthrax. B. anthracis virulence is partly attributable to two secreted bipartite protein toxins, which act inside host cells to disrupt signaling pathways important for host defense against infection. These toxins may also directly contribute to mortality in late stage infection. The zinc-dependent metalloproteinase anthrax lethal factor (LF) is a critical component of one of these protein toxins and a prime target for inhibitor development to produce anthrax therapeutics. Here, we describe recent efforts to identify specific and potent LF inhibitors. Derivatization of peptide substrate analogs bearing zinc-binding groups has produced potent and specific LF inhibitors, and X-ray crystallography of LFinhibitor complexes has provided insight into features required for high affinity binding. Novel inhibitor scaffolds have been identified through several approaches, including fragment-based drug discovery, virtual screening, and highthroughput screening of diverse compound libraries. Lastly, efforts to discover LF inhibitors have led to the development of new screening strategies, such as the use of full-length proteins as substrates, that may prove useful for other proteases as well. Overall, these efforts have led to a collection of chemically and mechanistically diverse molecules capable of inhibiting LF activity in vitro and in cells, as well as in animal models of anthrax infection. PMID:27072692

  14. Pulmonary edema

    MedlinePlus

    ... congestion; Lung water; Pulmonary congestion; Heart failure - pulmonary edema ... Pulmonary edema is often caused by congestive heart failure . When the heart is not able to pump efficiently, blood ...

  15. ANTHRAX TECHNICAL ASSISTANCE DOCUMENT

    EPA Science Inventory

    The Anthrax TAD was developed as an Interim Draft Final technical resource in November 2003. It is specifically for response to an actual or suspected terrorist release of anthrax (i.e., it is not intended for response to anthrax in agricultural settings.). The TAD was provided ...

  16. Presentation of peptides from Bacillus anthracis protective antigen on Tobacco Mosaic Virus as an epitope targeted anthrax vaccine.

    PubMed

    McComb, Ryan C; Ho, Chi-Lee; Bradley, Kenneth A; Grill, Laurence K; Martchenko, Mikhail

    2015-11-27

    The current anthrax vaccine requires improvements for rapidly invoking longer-lasting neutralizing antibody responses with fewer doses from a well-defined formulation. Designing antigens that target neutralizing antibody epitopes of anthrax protective antigen, a component of anthrax toxin, may offer a solution for achieving a vaccine that can induce strong and long lasting antibody responses with fewer boosters. Here we report implementation of a strategy for developing epitope focused virus nanoparticle vaccines against anthrax by using immunogenic virus particles to present peptides derived from anthrax toxin previously identified in (1) neutralizing antibody epitope mapping studies, (2) toxin crystal structure analyses to identify functional regions, and (3) toxin mutational analyses. We successfully expressed two of three peptide epitopes from anthrax toxin that, in previous reports, bound antibodies that were partially neutralizing against toxin activity, discovered cross-reactivity between vaccine constructs and toxin specific antibodies raised in goats against native toxin and showed that antibodies induced by our vaccine constructs also cross-react with native toxin. While protection against intoxication in cellular and animal studies were not as effective as in previous studies, partial toxin neutralization was observed in animals, demonstrating the feasibility of using plant-virus nanoparticles as a platform for epitope defined anthrax vaccines. PMID:26514421

  17. Different Roles of N-Terminal and C-Terminal Domains in Calmodulin for Activation of Bacillus anthracis Edema Factor

    PubMed Central

    Lübker, Carolin; Dove, Stefan; Tang, Wei-Jen; Urbauer, Ramona J. Bieber; Moskovitz, Jackob; Urbauer, Jeffrey L.; Seifert, Roland

    2015-01-01

    Bacillus anthracis adenylyl cyclase toxin edema factor (EF) is one component of the anthrax toxin and is essential for establishing anthrax disease. EF activation by the eukaryotic Ca2+-sensor calmodulin (CaM) leads to massive cAMP production resulting in edema. cAMP also inhibits the nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase, thus reducing production of reactive oxygen species (ROS) used for host defense in activated neutrophils and thereby facilitating bacterial growth. Methionine (Met) residues in CaM, important for interactions between CaM and its binding partners, can be oxidized by ROS. We investigated the impact of site-specific oxidation of Met in CaM on EF activation using thirteen CaM-mutants (CaM-mut) with Met to leucine (Leu) substitutions. EF activation shows high resistance to oxidative modifications in CaM. An intact structure in the C-terminal region of oxidized CaM is sufficient for major EF activation despite altered secondary structure in the N-terminal region associated with Met oxidation. The secondary structures of CaM-mut were determined and described in previous studies from our group. Thus, excess cAMP production and the associated impairment of host defence may be afforded even under oxidative conditions in activated neutrophils. PMID:26184312

  18. The anthrax vaccine: no new tricks for an old dog.

    PubMed

    Bienek, Diane R; Loomis, Lawrence J; Biagini, Raymond E

    2009-03-01

    The original license for production of the anthrax vaccine, Anthrax Vaccine Adsorbed (AVA), was issued in 1970. Since that time, over 8 million AVA immunizations have been administered to 2+ million individuals. In 2002, the National Academy of Sciences, Institute of Medicine, reviewed the safety and efficacy of AVA. They concluded that the vaccine is acceptably safe and effective in protecting humans against anthrax. The vaccine should protect people against all known strains of anthrax bacteria, as well as against any strains that might be created by potential terrorists or others. Although the Institute of Medicine concluded that AVA was reasonably safe, they noted that it is fairly common for people to experience local reactions (e.g., redness and swelling at the injection site) and for a smaller number to experience systemic reactions such as fever and malaise, within hours or days of vaccination. Results of animal studies done previously and subsequent to this report are generally in agreement. For instance, AVA vaccination increases the level of anthrax anti-protective antigen IgG (anti-PA IgG), which is thought to be one possible correlate of protection (although absolute protective concentrations have not been identified in humans). Anthrax lethal factor neutralization has also been identified as possibly being an important additional correlate of immunity. Future vaccine research efforts include developing a recombinant anthrax vaccine and anthrax monoclonal antibodies to block the anthrax toxin(s). It is projected that the next-generation vaccine will elicit a markedly increased anti-anthrax immune response within a shorter time period and consequently, will enable the easier inoculations of individuals working within high-risk areas. PMID:19270504

  19. An overview of anthrax infection including the recently identified form of disease in injection drug users

    PubMed Central

    Hicks, Caitlin W.; Sweeney, Daniel A.; Cui, Xizhong; Li, Yan

    2012-01-01

    Purpose Bacillus anthracis infection (anthrax) can be highly lethal. Two recent outbreaks related to contaminated mail in the USA and heroin in the UK and Europe and its potential as a bioterrorist weapon have greatly increased concerns over anthrax in the developed world. Methods This review summarizes the microbiology, pathogenesis, diagnosis, and management of anthrax. Results and conclusions Anthrax, a gram-positive bacterium, has typically been associated with three forms of infection: cutaneous, gastrointestinal, and inhalational. However, the anthrax outbreak among injection drug users has emphasized the importance of what is now considered a fourth disease form (i.e., injectional anthrax) that is characterized by severe soft tissue infection. While cutaneous anthrax is most common, its early stages are distinct and prompt appropriate treatment commonly produces a good outcome. However, early symptoms with the other three disease forms can be nonspecific and mistaken for less lethal conditions. As a result, patients with gastrointestinal, inhalational, or injectional anthrax may have advanced infection at presentation that can be highly lethal. Once anthrax is suspected, the diagnosis can usually be made with gram stain and culture from blood or tissue followed by confirmatory testing (e.g., PCR). While antibiotics are the mainstay of anthrax treatment, use of adjunctive therapies such as anthrax toxin antagonists are a consideration. Prompt surgical therapy appears to be important for successful management of injectional anthrax. PMID:22527064

  20. Rapid vascular responses to anthrax lethal toxin in mice containing a segment of chromosome 11 from the CAST/Ei strain on a C57BL/6 genetic background.

    PubMed

    Weigel, Kelsey J; Rues, Laura; Doyle, Edward J; Buchheit, Cassandra L; Wood, John G; Gallagher, Ryan J; Kelly, Laura E; Radel, Jeffrey D; Bradley, Kenneth A; LeVine, Steven M

    2012-01-01

    Host allelic variation controls the response to B. anthracis and the disease course of anthrax. Mouse strains with macrophages that are responsive to anthrax lethal toxin (LT) show resistance to infection while mouse strains with LT non-responsive macrophages succumb more readily. B6.CAST.11M mice have a region of chromosome 11 from the CAST/Ei strain (a LT responsive strain) introgressed onto a LT non-responsive C57BL/6J genetic background. Previously, B6.CAST.11M mice were found to exhibit a rapid inflammatory reaction to LT termed the early response phenotype (ERP), and displayed greater resistance to B. anthracis infection compared to C57BL/6J mice. Several ERP features (e.g., bloat, hypothermia, labored breathing, dilated pinnae vessels) suggested vascular involvement. To test this, Evan's blue was used to assess vessel leakage and intravital microscopy was used to monitor microvascular blood flow. Increased vascular leakage was observed in lungs of B6.CAST.11M mice compared to C57BL/6J mice 1 hour after systemic administration of LT. Capillary blood flow was reduced in the small intestine mesentery without concomitant leukocyte emigration following systemic or topical application of LT, the latter suggesting a localized tissue mechanism in this response. Since LT activates the Nlrp1b inflammasome in B6.CAST.11M mice, the roles of inflammasome products, IL-1β and IL-18, were examined. Topical application to the mesentery of IL-1β but not IL-18 revealed pronounced slowing of blood flow in B6.CAST.11M mice that was not present in C57BL/6J mice. A neutralizing anti-IL-1β antibody suppressed the slowing of blood flow induced by LT, indicating a role for IL-1β in the response. Besides allelic differences controlling Nlrp1b inflammasome activation by LT observed previously, evidence presented here suggests that an additional genetic determinant(s) could regulate the vascular response to IL-1β. These results demonstrate that vessel leakage and alterations to

  1. Inhibition of Interleukin 1β (IL-1β) Expression by Anthrax Lethal Toxin (LeTx) Is Reversed by Histone Deacetylase 8 (HDAC8) Inhibition in Murine Macrophages.

    PubMed

    Ha, Soon-Duck; Reid, Chantelle; Meshkibaf, Shahab; Kim, Sung Ouk

    2016-04-15

    Many pathogenic microbes often release toxins that subvert the host's immune responses to render the environment suitable for their survival and proliferation. LeTx is one of the toxins causing immune paralysis by cleaving and inactivating the mitogen-activated protein kinase (MAPK) kinases (MEKs). Here, we show that inhibition of the histone deacetylase 8 (HDAC8) by either the HDAC8-specific inhibitor PCI-34051 or small interference (si)RNAs rendered LeTx-exposed murine macrophages responsive to LPS in pro-IL-1β production. HDAC8 selectively targeted acetylated histone H3 lysine 27 (H3K27Ac), which is known to associate with active enhancers. LeTx induced HDAC8 expression, in part through inhibiting p38 MAPK, which resulted in a decrease of H3K27Ac levels. Inhibition of HDAC8 increased H3K27Ac levels and enhanced NF-κB-mediated pro-IL-1β enhancer and messenger RNA production in LeTx-exposed macrophages. Collectively, this study demonstrates a novel role of HDAC8 in LeTx immunotoxicity and regulation of pro-IL-1β production likely through eRNAs. Targeting HDAC8 could be a strategy for enhancing immune responses in macrophages exposed to LeTx or other toxins that inhibit MAPKs. PMID:26912657

  2. A review of cutaneous anthrax and its outcome.

    PubMed

    Doganay, Mehmet; Metan, Gokhan; Alp, Emine

    2010-01-01

    Anthrax is still an endemic disease in some countries in the world and has become a re-emerging disease in western countries with recent intentional outbreak. The aim of this study was to review our clinical experience with cutaneous anthrax cases. From the patient's files, transmission of the diseases, clinical findings and severity of infection, treatment and outcome of patients were recorded. Twenty-two cases were diagnosed as cutaneous anthrax in the last 7 years. Of these cases, 10 cases were severe form of cutaneous anthrax, 10 cases were mild form and 2 cases were toxemic shock due to cutaneous anthrax. The incubation period was between 1 and 17 days. The main clinical characteristics of the cases with severe cutaneous anthrax were fever, hemorrhagic bullous lesions surrounded by an extensive erythema and edema, and leukocytosis. Two cases with toxemic shock had low systolic blood pressure, apathy and toxemic appearance, leukocytosis, hypoalbuminemia & hyponatremia. Penicillin G was given in 15 cases, amoxicillin in 4 and other antibiotics in 3 cases for 3-10 days. Skin lesion left deep tissue scar in 4 cases and were grafted. Physicians working in endemic areas and also in western countries should be aware of all clinical forms of anthrax. PMID:20869669

  3. The Role of NF-κB and H3K27me3 Demethylase, Jmjd3, on the Anthrax Lethal Toxin Tolerance of RAW 264.7 Cells

    PubMed Central

    Das, Nando Dulal; Jung, Kyoung Hwa; Chai, Young Gyu

    2010-01-01

    Background In Bacillus anthracis, lethal toxin (LeTx) is a critical virulence factor that causes immune suppression and toxic shock in the infected host. NF-κB is a key mediator of the inflammatory response and is crucial for the plasticity of first level immune cells such as macrophages, monocytes and neutrophils. In macrophages, this inflammatory response, mediated by NF-κB, can regulate host defense against invading pathogens. A Jumonji C family histone 3 lysine-27 (H3K27) demethylase, Jmjd3, plays a crucial role in macrophage plasticity and inflammation. Here we report that NF-κB and Jmjd3 can modulate the LeTx intoxication resistance of RAW 264.7 cells. Principal Findings This study showed that a 2 h exposure of macrophages to LeTx caused substantial cell death with a survival rate of around 40%. The expression of the Jmjd3 gene was induced 8-fold in intoxication-resistant cells generated by treatment with lipopolysaccharides of RAW 264.7 cells. These intoxication-resistant cell lines (PLx intox and PLxL intox) were maintained for 8 passages and had a survival rate of around 100% on secondary exposure to LeTx and lipopolysaccharides. Analysis of NF-κB gene expression showed that the expression of p100, p50 and p65 was induced around 20, 7 and 4 fold, respectively, in both of the intoxication-resistant cell lines following a 2 h treatment with PLxL (0.1+0.1+1 µg/ml). In contrast, these NF-κB genes were not induced following treatment with PLx treatment at the same concentrations. Conclusions Although LeTx influences macrophage physiology and causes defects of some key signaling pathways such as GSK3β which contributes to cytotoxicity, these results indicate that modulation of NF-κB by p50, p100 and Jmjd3 could be vital for the recovery of murine macrophages from exposure to the anthrax lethal toxin. PMID:20360974

  4. ANTHRAX PROBLEM IN MASSACHUSETTS

    PubMed Central

    Osborn, Stanley H.

    1920-01-01

    Federal regulations do not prevent importation of anthrax infected material. This author suggests anthrax surveys in countries of origin of materials, quarantine of all hides, wool and hair from suspected areas, disinfection of these at places of origin and sanitary care here of wastes from hide and wool industrial establishments. Imagesp665-a PMID:18010353

  5. Investigation of a panel of monoclonal antibodies and polyclonal sera against anthrax toxins resulted in identification of an anti-lethal factor antibody with disease-enhancing characteristics.

    PubMed

    Kulshreshtha, Parul; Tiwari, Ashutosh; Priyanka; Joon, Shikha; Sinha, Subrata; Bhatnagar, Rakesh

    2015-12-01

    Hybridomas were created using spleen of mice that were actively immunized with rLFn (recombinant N-terminal domain of lethal factor). Later on, separate group of mice were immunized with rLFn to obtain a polyclonal control for passive immunization studies of monoclonal antibodies. This led to the identification of one cohort of rLFn-immnized mice that harboured disease-enhancing polyclonal antibodies. At the same time, the monoclonal antibodies secreted by all the hybridomas were being tested. Two hybridomas secreted monoclonal antibodies (H10 and H8) that were cross-reactive with EF (edema factor) and LF (lethal factor), while the other two hybridomas secreted LF-specific antibodies (H7 and H11). Single chain variable fragment (LETscFv) was derived from H10 hybridoma. H11 was found to have disease-enhancing property. Combination of H11 with protective monoclonal antibodies (H8 and H10) reduced its disease enhancing nature. This in vitro abrogation of disease-enhancement provides the proof of concept that in polyclonal sera the disease enhancing character of a fraction of antibodies is overshadowed by the protective nature of the rest of the antibodies generated on active immunization. PMID:26364143

  6. Clinical findings in children with cutaneous anthrax in eastern Turkey.

    PubMed

    Akbayram, Sinan; Doğan, Murat; Akgün, Cihangir; Peker, Erdal; Bektaş, M Selçuk; Kaya, Avni; Caksen, Hüseyin; Oner, Ahmet Faik

    2010-01-01

    Anthrax is a zoonosis produced by Bacillus anthracis. The aim of this study was to evaluate the clinical findings, therapy, and outcome in children with cutaneous anthrax (CA). Data on age, gender, occupation, clinical symptoms and findings, location and type of lesions, clinical history, laboratory findings, treatment, and outcome were recorded from patients' medical records, retrospectively. The study included 65 patients between 1 month and 18 years old (9.0±4.0 years), 37 patients (56.9%) were male and 28 (43.1%) were female. Most of the patients (89.1%) were admitted in summer and autumn (p<0.001). Of the 65 patients, 20 patients (30.8%) had received antibiotherapy before admission to our hospital. All patients except one had a contact history with infected animals. A 1-month-old patient had a contact history with his mother who had CA. On clinical examination, anthrax edema was noted in 36 (55.3%) patients, anthrax pustule in 27 (41.5%), and anthrax edema and anthrax pustule in two (3%) patients. Gram staining and culture was positive for B. anthracis in 35 (53.8%) patients, and only Gram staining was positive in 10 (15.4%) patients. In the remaining 20 (30.8%) patients, the diagnosis was made by clinical findings. Because the anthrax outbreak in Turkey was associated with slaughtering or milking of ill cows, sheep, or goats, and handling raw meat without taking any protective measures, persons in the community must be educated about using personal protective equipment during slaughtering of animals and handling of meat and skins. PMID:21083757

  7. Anthrax Lethal Toxin Induced Lysosomal Membrane Permeabilization and Cytosolic Cathepsin Release Is Nlrp1b/Nalp1b-Dependent

    PubMed Central

    Averette, Kathleen M.; Pratt, Matthew R.; Yang, Yanan; Bassilian, Sara; Whitelegge, Julian P.; Loo, Joseph A.; Muir, Tom W.; Bradley, Kenneth A.

    2009-01-01

    NOD-like receptors (NLRs) are a group of cytoplasmic molecules that recognize microbial invasion or ‘danger signals’. Activation of NLRs can induce rapid caspase-1 dependent cell death termed pyroptosis, or a caspase-1 independent cell death termed pyronecrosis. Bacillus anthracis lethal toxin (LT), is recognized by a subset of alleles of the NLR protein Nlrp1b, resulting in pyroptotic cell death of macrophages and dendritic cells. Here we show that LT induces lysosomal membrane permeabilization (LMP). The presentation of LMP requires expression of an LT-responsive allele of Nlrp1b, and is blocked by proteasome inhibitors and heat shock, both of which prevent LT-mediated pyroptosis. Further the lysosomal protease cathepsin B is released into the cell cytosol and cathepsin inhibitors block LT-mediated cell death. These data reveal a role for lysosomal membrane permeabilization in the cellular response to bacterial pathogens and demonstrate a shared requirement for cytosolic relocalization of cathepsins in pyroptosis and pyronecrosis. PMID:19924255

  8. Anthrax lethal toxin impairs CD1d-mediated antigen presentation by targeting the extracellular signal-related kinase 1/2 mitogen-activated protein kinase pathway.

    PubMed

    Khan, Masood A; Gallo, Richard M; Brutkiewicz, Randy R

    2010-05-01

    Lethal toxin (LT) is a critical virulence factor of Bacillus anthracis and an important means by which this bacterium evades the host's immune system. In this study, we demonstrate that CD1d-expressing cells treated with LT have reduced CD1d-mediated antigen presentation. We earlier showed an important role for the mitogen-activated protein kinase extracellular signal-regulated kinase 1/2 (ERK1/2) in the regulation of CD1d-mediated antigen presentation, and we report here that LT impairs antigen presentation by CD1d in an ERK1/2-dependent manner. Similarly, LT and the ERK1/2 pathway-specific inhibitor U0126 caused a decrease in major histocompatibility complex (MHC) class II-mediated antigen presentation. Confocal microscopy analyses revealed altered intracellular distribution of CD1d and LAMP-1 in LT-treated cells, similar to the case for ERK1/2-inhibited cells. These results suggest that Bacillus anthracis has the ability to evade the host's innate immune system by reducing CD1d-mediated antigen presentation through targeting the ERK1/2 pathway. PMID:20194602

  9. [Anthrax--continuous threat to humans and animals].

    PubMed

    Mizak, Lidia

    2004-01-01

    Gram-positive, spore-forming, aerobic bacterium Bacillus anthracis is an etiological agent of anthrax a disease very dangerous to humans and all warm-blooded animals. The spore forms are markedly resistant to unfavourable environmental extremes of heat, cold, desiccation, chemicals, irradiation etc. The vegetative forms characterised virulence factors: the antiphagocytic poly-gamma-D-polipeptide capsule and three proteins, edema factor (EF), lethal factor (LF) and protective antigen (PA). Anthrax is mainly transmitted from animals to man through food of animal origin, animal products and contamination of the environment with B. anthracis and its spores. There are three types of this disease: cutaneous, intestinal and inhalation anthrax. Research on anthrax as a biological weapon began more then 80 years ago. Depending on the target chosen and the scale of the attack the anthrax spores may by used to contaminate of foodstuffs or liquids and water. The aerosolised release of anthrax spore can cause illness with a high fatality rate. PMID:15517814

  10. Anthrax-associated shock.

    PubMed

    Goldman, David L; Casadevall, Arturo

    2008-01-01

    Recent events have brought attention to the potential of Bacillus anthracis as an agent of bioterrorism. The shock like state of anthrax is invariably associated with high mortality, despite anti-microbial and supportive therapy. Multi-system dysfunction is typical, including: enhanced vascular permeability, hemorrhage and inflammation. Important questions concerning the pathophysiology of anthrax-associated shock remain unanswered, including the effects of B. anthracis infection on cardiac function. This review discusses the current state of knowledge regarding the pathophysiology of anthrax-associated shock. PMID:18508494

  11. Development of a Sterne-Based Complement Fixation Test to Monitor the Humoral Response Induced by Anthrax Vaccines

    PubMed Central

    Adone, Rosanna; Sali, Michela; Francia, Massimiliano; Iatarola, Michela; Donatiello, Adelia; Fasanella, Antonio

    2016-01-01

    Anthrax is a zoonotic disease caused by Bacillus anthracis spore-forming bacterium. Since it is primarily a disease of animals, the control in animals, and humans depend on the prevention in livestock, principally cattle, sheep, and goats. Most veterinary vaccines utilize the toxigenic, uncapsulated (pXO1+/pXO2–) B. anthracis strain 34F2 which affords protection through the production of neutralizing antibodies directed to the toxin components Protective Antigen (PA), Lethal Factor (LF), and Edema Factor (EF). The titration of specific antibodies in sera of vaccinated animals is crucial to evaluate the efficacy of the vaccination and to obtain epidemiological information for an effective anthrax surveillance. In this study, we developed a Sterne-based Complement Fixation Test (CFT) to detect specific antibodies induced in animals vaccinated with Sterne 34F2. We assessed its efficacy in laboratory animals and under field conditions by monitoring the humoral response induced by vaccination in cattle. The results indicated that the Sterne-based CFT is able to correctly identify vaccinated animals. It proved to be a very sensitive and specific test. Moreover, the Sterne-based CFT offers many benefits with regard to costs, standardization and reproducibility of the assay procedure. PMID:26858700

  12. Development of a Sterne-Based Complement Fixation Test to Monitor the Humoral Response Induced by Anthrax Vaccines.

    PubMed

    Adone, Rosanna; Sali, Michela; Francia, Massimiliano; Iatarola, Michela; Donatiello, Adelia; Fasanella, Antonio

    2016-01-01

    Anthrax is a zoonotic disease caused by Bacillus anthracis spore-forming bacterium. Since it is primarily a disease of animals, the control in animals, and humans depend on the prevention in livestock, principally cattle, sheep, and goats. Most veterinary vaccines utilize the toxigenic, uncapsulated (pXO1+/pXO2-) B. anthracis strain 34F2 which affords protection through the production of neutralizing antibodies directed to the toxin components Protective Antigen (PA), Lethal Factor (LF), and Edema Factor (EF). The titration of specific antibodies in sera of vaccinated animals is crucial to evaluate the efficacy of the vaccination and to obtain epidemiological information for an effective anthrax surveillance. In this study, we developed a Sterne-based Complement Fixation Test (CFT) to detect specific antibodies induced in animals vaccinated with Sterne 34F2. We assessed its efficacy in laboratory animals and under field conditions by monitoring the humoral response induced by vaccination in cattle. The results indicated that the Sterne-based CFT is able to correctly identify vaccinated animals. It proved to be a very sensitive and specific test. Moreover, the Sterne-based CFT offers many benefits with regard to costs, standardization and reproducibility of the assay procedure. PMID:26858700

  13. ANTHRAX REMEDIATION RESEARCH NEEDS

    EPA Science Inventory

    The Environmental Protection Agency has initiated a research program to respond to the immediate needs arising from the recent Bacillus anthracis bioterrorism events. Although the program has a strong emphasis on anthrax, other pathogens and chemical agents, including toxic indu...

  14. Anthrax blood test

    MedlinePlus

    ... test; Antibody test for anthrax; Serologic test for B anthracis ... Hall GS, Woods GL. Medical bacteriology. In: McPherson RA, Pincus ... Philadelphia, PA: Elsevier Saunders; 2011:chap 57. Martin GJ, ...

  15. Anthrax vaccination strategies

    PubMed Central

    Cybulski, Robert J.; Sanz, Patrick; O'Brien, Alison D.

    2009-01-01

    The biological attack conducted through the U.S. postal system in 2001 broadened the threat posed by anthrax from one pertinent mainly to soldiers on the battlefield to one understood to exist throughout our society. The expansion of the threatened population placed greater emphasis on the reexamination of how we vaccinate against Bacillus anthracis. The currently-licensed Anthrax Vaccine, Adsorbed (AVA) and Anthrax Vaccine, Precipitated (AVP) are capable of generating a protective immune response but are hampered by shortcomings that make their widespread use undesirable or infeasible. Efforts to gain U.S. Food and Drug Administration (FDA) approval for licensure of a second generation recombinant protective antigen (rPA)-based anthrax vaccine are ongoing. However, this vaccine's reliance on the generation of a humoral immune response against a single virulence factor has led a number of scientists to conclude that the vaccine is likely not the final solution to optimal anthrax vaccine design. Other vaccine approaches, which seek a more comprehensive immune response targeted at multiple components of the B. anthracis organism, are under active investigation. This review seeks to summarize work that has been done to build on the current PA-based vaccine methodology and to evaluate the search for future anthrax prophylaxis strategies. PMID:19729034

  16. Deletion modification enhances anthrax specific immunity and protective efficacy of a hepatitis B core particle-based anthrax epitope vaccine.

    PubMed

    Yin, Ying; Zhang, Sheng; Cai, Chenguang; Zhang, Jun; Dong, Dayong; Guo, Qiang; Fu, Ling; Xu, Junjie; Chen, Wei

    2014-02-01

    Protective antigen (PA) is one of the major virulence factors of anthrax and is also the major constituent of the current anthrax vaccine. Previously, we found that the 2β2-2β3 loop of PA contains a dominant neutralizing epitope, the SFFD. We successfully inserted the 2β2-2β3 loop of PA into the major immunodominant region (MIR) of hepatitis B virus core (HBc) protein. The resulting fusion protein, termed HBc-N144-PA-loop2 (HBcL2), can effectively produce anthrax specific protective antibodies in an animal model. However, the protective immunity caused by HBcL2 could still be improved. In this research, we removed amino acids 79-81 from the HBc MIR of the HBcL2. This region was previously reported to be the major B cell epitope of HBc, and in keeping with this finding, we observed that the short deletion in the MIR not only diminished the intrinsic immunogenicity of HBc but also stimulated a higher titer of anthrax specific immunity. Most importantly, this deletion led to the full protection of the immunized mice against a lethal dose anthrax toxin challenge. We supposed that the conformational changes which occurred after the short deletion and foreign insertion in the MIR of HBc were the most likely reasons for the improvement in the immunogenicity of the HBc-based anthrax epitope vaccine. PMID:24054942

  17. Antitoxin Treatment of Inhalation Anthrax: A Systematic Review.

    PubMed

    Huang, Eileen; Pillai, Satish K; Bower, William A; Hendricks, Katherine A; Guarnizo, Julie T; Hoyle, Jamechia D; Gorman, Susan E; Boyer, Anne E; Quinn, Conrad P; Meaney-Delman, Dana

    2015-01-01

    Concern about use of anthrax as a bioweapon prompted development of novel anthrax antitoxins for treatment. Clinical guidelines for the treatment of anthrax recommend antitoxin therapy in combination with intravenous antimicrobials; however, a large-scale or mass anthrax incident may exceed antitoxin availability and create a need for judicious antitoxin use. We conducted a systematic review of antitoxin treatment of inhalation anthrax in humans and experimental animals to inform antitoxin recommendations during a large-scale or mass anthrax incident. A comprehensive search of 11 databases and the FDA website was conducted to identify relevant animal studies and human reports: 28 animal studies and 3 human cases were identified. Antitoxin monotherapy at or shortly after symptom onset demonstrates increased survival compared to no treatment in animals. With early treatment, survival did not differ between antimicrobial monotherapy and antimicrobial-antitoxin therapy in nonhuman primates and rabbits. With delayed treatment, antitoxin-antimicrobial treatment increased rabbit survival. Among human cases, addition of antitoxin to combination antimicrobial treatment was associated with survival in 2 of the 3 cases treated. Despite the paucity of human data, limited animal data suggest that adjunctive antitoxin therapy may improve survival. Delayed treatment studies suggest improved survival with combined antitoxin-antimicrobial therapy, although a survival difference compared with antimicrobial therapy alone was not demonstrated statistically. In a mass anthrax incident with limited antitoxin supplies, antitoxin treatment of individuals who have not demonstrated a clinical benefit from antimicrobials, or those who present with more severe illness, may be warranted. Additional pathophysiology studies are needed, and a point-of-care assay correlating toxin levels with clinical status may provide important information to guide antitoxin use during a large-scale anthrax

  18. Pulmonary Edema

    PubMed Central

    Tanser, Paul H.

    1980-01-01

    The physician who deals with pulmonary edema from a pathophysiologic basis will seldom make a diagnostic or therapeutic error. Recent additions to preload and afterload therapy have greatly helped in the emergency and ambulatory treatment of pulmonary edema due to left heart failure. Careful follow-up and patient self-monitoring are the most effective means of reducing hospitalization of chronic heart failure patients. PMID:21293700

  19. Toxins as Weapons: A Historical Review.

    PubMed

    Pita, R; Romero, A

    2014-07-01

    This review article summarizes the use of toxins as weapons dating from the First World War until today, when there is a high concern of possible terrorist attacks with weapons of mass destruction. All through modern history, military programs and terrorist groups have favored toxins because of their high toxicity. However, difficulties of extraction or synthesis, as well as effective dissemination to cause a large number of casualties, have been the most important drawbacks. Special emphasis is focused on ricin and botulinum toxin, the most important toxins that have attracted the attention of military programs and terrorist groups. Other toxins like trichothecenes, saxitoxin, and Staphylococcal enterotoxin B (SEB) are also discussed. A short section about anthrax is also included: Although Bacillus anthracis is considered a biological weapon rather than a toxin weapon, it produces a toxin that is finally responsible for the anthrax disease. PMID:26227025

  20. Anthrax in the Gambia: an epidemiological study

    PubMed Central

    Heyworth, B; Ropp, M E; Voos, U G; Meinel, H I; Darlow, H M

    1975-01-01

    Epidemiological data on 448 cases of human cutaneous anthrax from the Gambia showed that this particular strain of anthrax bacillus causes widespread morbidity and some mortality with, at the same time, subclinical infection. Analysis also showed that anthrax is not an occupationally related disease in the Gambia. The possibility of human-to-human spread, affecting all age groups and both sexes, by means of a communal toilet article was also shown. The fact that the strain is a good toxin producer but contains a weak antigen may have accounted for the repeated clinical infection and the fact that antibody titres were generally transient. Subclinical infection in animals was also found, particularly in sheep and goats, and also, with an unusually low mortality, in cows. Insect vectors were not excluded, but were unlikely. Vultures may spread the disease from village to village. Some possible public health and immunization procedures are discussed, with a view to containing this difficult problem in this part of west Africa. PMID:810213

  1. Nanopore Biosensor for Label-Free and Real-Time Detection of Anthrax Lethal Factor

    PubMed Central

    2015-01-01

    We report a label-free real-time nanopore sensing method for the detection of anthrax lethal factor, a component of the anthrax toxin, by using a complementary single-stranded DNA as a molecular probe. The method is rapid and sensitive: sub-nanomolar concentrations of the target anthrax lethal factor DNA could be detected in ∼1 min. Further, our method is selective, which can differentiate the target DNA from other single-stranded DNA molecules at the single-base resolution. This sequence-specific detection approach should find useful application in the development of nanopore sensors for the detection of other pathogens. PMID:24806593

  2. A conserved motif in transmembrane helix 1 of diphtheria toxin mediates catalytic domain delivery to the cytosol

    PubMed Central

    Ratts, Ryan; Trujillo, Carolina; Bharti, Ajit; vanderSpek, Johanna; Harrison, Robert; Murphy, John R.

    2005-01-01

    A 10-aa motif in transmembrane helix 1 of diphtheria toxin that is conserved in anthrax edema factor, anthrax lethal factor, and botulinum neurotoxin serotypes A, C, and D was identified by blast, clustal w, and meme computational analysis. Using the diphtheria toxin-related fusion protein toxin DAB389IL-2, we demonstrate that introduction of the L221E mutation into a highly conserved residue within this motif results in a nontoxic catalytic domain translocation deficient phenotype. To further probe the function of this motif in the process by which the catalytic domain is delivered from the lumen of early endosomes to the cytosol, we constructed a gene encoding a portion of diphtheria toxin transmembrane helix 1, T1, which carries the motif and is expressed from a CMV promoter. We then isolated stable transfectants of Hut102/6TG cells that express the T1 peptide, Hut102/6TG-T1. In contrast to the parental cell line, Hut102/6TG-T1 cells are ca. 104-fold more resistant to the fusion protein toxin. This resistance is completely reversed by coexpression of small interfering RNA directed against the gene encoding the T1 peptide in Hut102/6TG-T1 cells. We further demonstrate by GST-DT140-271 pull-down experiments in the presence and absence of synthetic T1 peptides the specific binding of coatomer protein complex subunit β to this region of the diphtheria toxin transmembrane domain. PMID:16230620

  3. Evaluation of Intravenous Anthrax Immune Globulin for Treatment of Inhalation Anthrax

    PubMed Central

    Mytle, Nutan; Hopkins, Robert J.; Malkevich, Nina V.; Basu, Subhendu; Meister, Gabriel T.; Sanford, Daniel C.; Comer, Jason E.; Van Zandt, Kristopher E.; Al-Ibrahim, Mohamed; Kramer, William G.; Howard, Cris; Daczkowski, Nancy; Chakrabarti, Ajoy C.; Ionin, Boris; Nabors, Gary S.

    2013-01-01

    Bacillus anthracis toxins can be neutralized by antibodies against protective antigen (PA), a component of anthrax toxins. Anthrivig (human anthrax immunoglobulin), also known as AIGIV, derived from plasma of humans immunized with BioThrax (anthrax vaccine adsorbed), is under development for the treatment of toxemia following exposure to anthrax spores. The pharmacokinetics (PK) of AIGIV was assessed in naive animals and healthy human volunteers, and the efficacy of AIGIV was assessed in animals exposed via inhalation to aerosolized B. anthracis spores. In the clinical study, safety, tolerability, and PK were evaluated in three dose cohorts (3.5, 7.1, and 14.2 mg/kg of body weight of anti-PA IgG) with 30 volunteers per cohort. The elimination half-life of AIGIV in rabbits, nonhuman primates (NHPs), and humans following intravenous infusion was estimated to be approximately 4, 12, and 24 days, respectively, and dose proportionality was observed. In a time-based treatment study, AIGIV protected 89 to 100% of animals when administered 12 h postexposure; however, a lower survival rate of 39% was observed when animals were treated 24 h postexposure, underscoring the need for early intervention. In a separate set of studies, animals were treated on an individual basis upon detection of a clinical sign or biomarker of disease, namely, a significant increase in body temperature (SIBT) in rabbits and presence of PA in the serum of NHPs. In these trigger-based intervention studies, AIGIV induced up to 75% survival in rabbits depending on the dose and severity of toxemia at the time of treatment. In NHPs, up to 33% survival was observed in AIGIV-treated animals. (The clinical study has been registered at ClinicalTrials.gov under registration no. NCT00845650.) PMID:23979731

  4. Anthrax Lethal Factor as an Immune Target in Humans and Transgenic Mice and the Impact of HLA Polymorphism on CD4+ T Cell Immunity

    PubMed Central

    Ascough, Stephanie; Ingram, Rebecca J.; Chu, Karen K.; Reynolds, Catherine J.; Musson, Julie A.; Doganay, Mehmet; Metan, Gökhan; Ozkul, Yusuf; Baillie, Les; Sriskandan, Shiranee; Moore, Stephen J.; Gallagher, Theresa B.; Dyson, Hugh; Williamson, E. Diane; Robinson, John H.; Maillere, Bernard; Boyton, Rosemary J.; Altmann, Daniel M.

    2014-01-01

    Bacillus anthracis produces a binary toxin composed of protective antigen (PA) and one of two subunits, lethal factor (LF) or edema factor (EF). Most studies have concentrated on induction of toxin-specific antibodies as the correlate of protective immunity, in contrast to which understanding of cellular immunity to these toxins and its impact on infection is limited. We characterized CD4+ T cell immunity to LF in a panel of humanized HLA-DR and DQ transgenic mice and in naturally exposed patients. As the variation in antigen presentation governed by HLA polymorphism has a major impact on protective immunity to specific epitopes, we examined relative binding affinities of LF peptides to purified HLA class II molecules, identifying those regions likely to be of broad applicability to human immune studies through their ability to bind multiple alleles. Transgenics differing only in their expression of human HLA class II alleles showed a marked hierarchy of immunity to LF. Immunogenicity in HLA transgenics was primarily restricted to epitopes from domains II and IV of LF and promiscuous, dominant epitopes, common to all HLA types, were identified in domain II. The relevance of this model was further demonstrated by the fact that a number of the immunodominant epitopes identified in mice were recognized by T cells from humans previously infected with cutaneous anthrax and from vaccinated individuals. The ability of the identified epitopes to confer protective immunity was demonstrated by lethal anthrax challenge of HLA transgenic mice immunized with a peptide subunit vaccine comprising the immunodominant epitopes that we identified. PMID:24788397

  5. Evaluation of Recombinant Forms of the Shiga Toxin Variant Stx2eB Subunit and Non-Toxic Mutant Stx2e as Vaccine Candidates against Porcine Edema Disease

    PubMed Central

    SATO, Toshio; MATSUI, Takeshi; TAKITA, Eiji; KADOYAMA, Yumiko; MAKINO, Sou-Ichi; KATO, Ko; SAWADA, Kazutoshi; HAMABATA, Takashi

    2013-01-01

    ABSTRACT Porcine edema disease (ED) is a communicable disease of shoats caused by infection with Shiga toxin (Stx)-producing Escherichia coli. Stx2e is classified as a 1A5B-type toxin and is a decisive virulence determinant of ED. The single A subunit of Stx2e possesses enzymatic activity and is accompanied by a pentamer of B subunits, which binds to the host receptor and delivers the A subunit into the cell. In the present study, we used a mouse model to evaluate the immunogenicity of 3 ED vaccine candidates: a non-toxic mutant holotoxin mStx2e and 2 Stx2eB-based fusion proteins, Stx2eA2B-His and Stx2eB-His. Systemic inoculation of mice with mStx2e- and the Stx2eB-derived antigens induced anti-Stx2e IgG responses that were fully and partially capable of neutralizing Stx2e cellular cytotoxicity, respectively. Intranasal immunization with mStx2e protected the mice from subsequent intraperitoneal challenge with a lethal dose of Stx2e, whereas immunization with Stx2eA2B-His and Stx2eB-His afforded partial protection. Analysis of serum cytokines revealed that mStx2e, but not the Stx2eB-based antigens, was capable of inducing a Th2-type immune response. These results suggest that although the Stx2eB-based antigens elicited an immune response to Stx2e, they did so through a different mechanism to the Th2-type response induced by mStx2e. PMID:23728257

  6. Methods for neutralizing anthrax or anthrax spores

    DOEpatents

    Sloan, Mark A; Vivekandanda, Jeevalatha; Holwitt, Eric A; Kiel, Johnathan L

    2013-02-26

    The present invention concerns methods, compositions and apparatus for neutralizing bioagents, wherein bioagents comprise biowarfare agents, biohazardous agents, biological agents and/or infectious agents. The methods comprise exposing the bioagent to an organic semiconductor and exposing the bioagent and organic semiconductor to a source of energy. Although any source of energy is contemplated, in some embodiments the energy comprises visible light, ultraviolet, infrared, radiofrequency, microwave, laser radiation, pulsed corona discharge or electron beam radiation. Exemplary organic semiconductors include DAT and DALM. In certain embodiments, the organic semiconductor may be attached to one or more binding moieties, such as an antibody, antibody fragment, or nucleic acid ligand. Preferably, the binding moiety has a binding affinity for one or more bioagents to be neutralized. Other embodiments concern an apparatus comprising an organic semiconductor and an energy source. In preferred embodiments, the methods, compositions and apparatus are used for neutralizing anthrax spores.

  7. Pediatric Anthrax Clinical Management

    PubMed Central

    Bradley, John S.; Peacock, Georgina; Krug, Steven E.; Bower, William A.; Cohn, Amanda C.; Meaney-Delman, Dana; Pavia, Andrew T.

    2015-01-01

    Anthrax is a zoonotic disease caused by Bacillus anthracis, which has multiple routes of infection in humans, manifesting in different initial presentations of disease. Because B anthracis has the potential to be used as a biological weapon and can rapidly progress to systemic anthrax with high mortality in those who are exposed and untreated, clinical guidance that can be quickly implemented must be in place before any intentional release of the agent. This document provides clinical guidance for the prophylaxis and treatment of neonates, infants, children, adolescents, and young adults up to the age of 21 (referred to as “children”) in the event of a deliberate B anthracis release and offers guidance in areas where the unique characteristics of children dictate a different clinical recommendation from adults. PMID:24777226

  8. Mapping the epitopes of a neutralizing antibody fragment directed against the lethal factor of Bacillus anthracis and cross-reacting with the homologous edema factor.

    PubMed

    Thullier, Philippe; Avril, Arnaud; Mathieu, Jacques; Behrens, Christian K; Pellequer, Jean-Luc; Pelat, Thibaut

    2013-01-01

    The lethal toxin (LT) of Bacillus anthracis, composed of the protective antigen (PA) and the lethal factor (LF), plays an essential role in anthrax pathogenesis. PA also interacts with the edema factor (EF, 20% identity with LF) to form the edema toxin (ET), which has a lesser role in anthrax pathogenesis. The first recombinant antibody fragment directed against LF was scFv 2LF; it neutralizes LT by blocking the interaction between PA and LF. Here, we report that scFv 2LF cross-reacts with EF and cross-neutralizes ET, and we present an in silico method taking advantage of this cross-reactivity to map the epitope of scFv 2LF on both LF and EF. This method identified five epitope candidates on LF, constituted of a total of 32 residues, which were tested experimentally by mutating the residues to alanine. This combined approach precisely identified the epitope of scFv 2LF on LF as five residues (H229, R230, Q234, L235 and Y236), of which three were missed by the consensus epitope candidate identified by pre-existing in silico methods. The homolog of this epitope on EF (H253, R254, E258, L259 and Y260) was experimentally confirmed to constitute the epitope of scFv 2LF on EF. Other inhibitors, including synthetic molecules, could be used to target these epitopes for therapeutic purposes. The in silico method presented here may be of more general interest. PMID:23741517

  9. Anthrax Spores under a microscope

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Anthrax spores are inactive forms of Bacillus anthracis. They can survive for decades inside a spore's tough protective coating; they become active when inhaled by humans. A result of NASA- and industry-sponsored research to develop small greenhouses for space research is the unique AiroCide TiO2 system that kills anthrax spores and other pathogens.

  10. Quantitative high throughput screening identifies inhibitors of anthrax-induced cell death

    PubMed Central

    Zhu, Ping Jun; Hobson, Peyton; Southall, Noel; Qiu, Cunping; Thomas, Craig J.; Lu, Jiamo; Inglese, James; Zheng, Wei; Leppla, Stephen H.; Bugge, Thomas H.; Austin, Christopher P.; Liu, Shihui

    2009-01-01

    Here, we report the results of a quantitative high-throughput screen (qHTS) measuring the endocytosis and translocation of a β-lactamase-fused-lethal factor and the identification of small molecules capable of obstructing the process of anthrax toxin internalization. Several small molecules protect RAW264.7 macrophages and CHO cells from anthrax lethal toxin and protected cells from an LF-Pseudomonas exotoxin fusion protein and diphtheria toxin. Further efforts demonstrated that these compounds impaired the PA heptamer pre-pore to pore conversion in cells expressing the CMG2 receptor, but not the related TEM8 receptor, indicating that these compounds likely interfere with toxin internalization. PMID:19540764

  11. Periocular cutaneous anthrax in Jimma Zone, Southwest Ethiopia: a case series

    PubMed Central

    2013-01-01

    Background Anthrax is a zoonotic disease caused by Bacillus anthracis. Naturally occurring human infection is rare and is generally the result of contact with anthrax-infected animals or animal products. Case presentation We examined three patients who had contact with presumed anthrax-infected animal and/or its product and presented with preseptal cellulitis with a localized itchy erythematous papule of the eyelid and non-pitting periorbital edema, followed by ulceration and dark eschar formation. All the three patients responded to intravenous antibiotics, and the lesion resolved leaving scars which caused cicatricial ectropion in all cases. Conclusion Anthrax is a rare disease but should be considered in the differential diagnosis of ulcerative (and eschar forming) preseptal cellulitis with a history of contact with anthrax-infected animals or animal products. Furthermore, cicatrization of the eyelids, one of the sequelae of periocular cutaneous anthrax, should be addressed. Urgent case report to the local zoonotic disease and infection control body and other responsible authorities is recommended. PMID:23924443

  12. Advances in the development of next-generation anthrax vaccines.

    PubMed

    Friedlander, Arthur M; Little, Stephen F

    2009-11-01

    Anthrax, a disease of herbivores, only rarely infects humans. However, the threat of using Bacillus anthracis, the causative agent, to intentionally produce disease has been the impetus for development of next-generation vaccines. Two licensed vaccines have been available for human use for several decades. These are composed of acellular culture supernatants containing the protective antigen (PA) component of the anthrax toxins. In this review we summarize the various approaches used to develop improved vaccines. These efforts have included the use of PA with newer adjuvants and delivery systems, including bacterial and viral vectors and DNA vaccines. Attempts to broaden the protection afforded by PA-based vaccines have focused on adding other B. anthracis components, including spore and capsule antigens. PMID:19837282

  13. Pathology and Pathophysiology of Inhalational Anthrax in a Guinea Pig Model

    PubMed Central

    Savransky, Vladimir; Sanford, Daniel C.; Syar, Emily; Austin, Jamie L.; Tordoff, Kevin P.; Anderson, Michael S.; Stark, Gregory V.; Barnewall, Roy E.; Briscoe, Crystal M.; Lemiale-Biérinx, Laurence; Park, Sukjoon; Ionin, Boris

    2013-01-01

    Nonhuman primates (NHPs) and rabbits are the animal models most commonly used to evaluate the efficacy of medical countermeasures against anthrax in support of licensure under the FDA's “Animal Rule.” However, a need for an alternative animal model may arise in certain cases. The development of such an alternative model requires a thorough understanding of the course and manifestation of experimental anthrax disease induced under controlled conditions in the proposed animal species. The guinea pig, which has been used extensively for anthrax pathogenesis studies and anthrax vaccine potency testing, is a good candidate for such an alternative model. This study was aimed at determining the median lethal dose (LD50) of the Bacillus anthracis Ames strain in guinea pigs and investigating the natural history, pathophysiology, and pathology of inhalational anthrax in this animal model following nose-only aerosol exposure. The inhaled LD50 of aerosolized Ames strain spores in guinea pigs was determined to be 5.0 × 104 spores. Aerosol challenge of guinea pigs resulted in inhalational anthrax with death occurring between 46 and 71 h postchallenge. The first clinical signs appeared as early as 36 h postchallenge. Cardiovascular function declined starting at 20 h postexposure. Hematogenous dissemination of bacteria was observed microscopically in multiple organs and tissues as early as 24 h postchallenge. Other histopathologic findings typical of disseminated anthrax included suppurative (heterophilic) inflammation, edema, fibrin, necrosis, and/or hemorrhage in the spleen, lungs, and regional lymph nodes and lymphocyte depletion and/or lymphocytolysis in the spleen and lymph nodes. This study demonstrated that the course of inhalational anthrax disease and the resulting pathology in guinea pigs are similar to those seen in rabbits and NHPs, as well as in humans. PMID:23357384

  14. Detection of anthrax protective antigen (PA) using europium labeled anti-PA monoclonal antibody and time-resolved fluorescence.

    PubMed

    Stoddard, Robyn A; Quinn, Conrad P; Schiffer, Jarad M; Boyer, Anne E; Goldstein, Jason; Bagarozzi, Dennis A; Soroka, Stephen D; Dauphin, Leslie A; Hoffmaster, Alex R

    2014-06-01

    Inhalation anthrax is a rare but acute infectious disease following adsorption of Bacillus anthracis spores through the lungs. The disease has a high fatality rate if untreated, but early and correct diagnosis has a significant impact on case patient recovery. The early symptoms of inhalation anthrax are, however, non-specific and current anthrax diagnostics are primarily dependent upon culture and confirmatory real-time PCR. Consequently, there may be a significant delay in diagnosis and targeted treatment. Rapid, culture-independent diagnostic tests are therefore needed, particularly in the context of a large scale emergency response. The aim of this study was to evaluate the ability of monoclonal antibodies to detect anthrax toxin proteins that are secreted early in the course of B. anthracis infection using a time-resolved fluorescence (TRF) immunoassay. We selected monoclonal antibodies that could detect protective antigen (PA), as PA83 and also PA63 and LF in the lethal toxin complex. The assay reliable detection limit (RDL) was 6.63×10(-6)μM (0.551ng/ml) for PA83 and 2.51×10(-5)μM (1.58ng/ml) for PA63. Despite variable precision and accuracy of the assay, PA was detected in 9 out of 10 sera samples from anthrax confirmed case patients with cutaneous (n=7), inhalation (n=2), and gastrointestinal (n=1) disease. Anthrax Immune Globulin (AIG), which has been used in treatment of clinical anthrax, interfered with detection of PA. This study demonstrates a culture-independent method of diagnosing anthrax through the use of monoclonal antibodies to detect PA and LF in the lethal toxin complex. PMID:24857756

  15. Progress and novel strategies in vaccine development and treatment of anthrax.

    PubMed

    Chitlaru, Theodor; Altboum, Zeev; Reuveny, Shaul; Shafferman, Avigdor

    2011-01-01

    The lethal anthrax disease is caused by spores of the gram-positive Bacillus anthracis, a member of the cereus group of bacilli. Although the disease is very rare in the Western world, development of anthrax countermeasures gains increasing attention due to the potential use of B. anthracis spores as a bio-terror weapon. Protective antigen (PA), the non-toxic subunit of the bacterial secreted exotoxin, fulfills the role of recognizing a specific receptor and mediating the entry of the toxin into the host target cells. PA elicits a protective immune response and represents the basis for all current anthrax vaccines. Anti-PA neutralizing antibodies are useful correlates for protection and for vaccine efficacy evaluation. Post exposure anti-toxemic and anti-bacteremic prophylactic treatment of anthrax requires prolonged antibiotic administration. Shorter efficient postexposure treatments may require active or passive immunization, in addition to antibiotics. Although anthrax is acknowledged as a toxinogenic disease, additional factors, other than the bacterial toxin, may be involved in the virulence of B. anthracis and may be needed for the long-lasting protection conferred by PA immunization. The search for such novel factors is the focus of several high throughput genomic and proteomic studies that are already leading to identification of novel targets for therapeutics, for vaccine candidates, as well as biomarkers for detection and diagnosis. PMID:21198675

  16. From Structure to Solutions: The Role of Basic Research in Developing Anthrax Countermeasures

    PubMed Central

    Hardiman, Camille A.

    2012-01-01

    Dr. John Collier traced the discoveries that elucidated the structure and function of the anthrax toxin in his talk “Anthrax Toxin,” which was part of the Microbiology Graduate Program Seminar Series at Yale School of Medicine on February 23, 2012. Dr. Collier, Professor of Microbiology and Immunobiology at Harvard University, began by noting the advantages to studying anthrax pathogenesis in a biosafety level-1 lab. This designation does not merely facilitate his research, but also reflects a larger trend of basic research being leveraged to develop translational applications. Basic research on toxin structure has led to the development of a vaccine by Dr. Collier’s group. Next-generation prophylactics also may stem from recent discoveries uncovering a role for cellular cofactors that mediate toxin function. Finally, basic research into the toxin substructure has facilitated efforts to change the receptor tropism to target dysregulated cells for therapeutic purposes. The urgency around biodefense agents makes the choice of research priorities a salient issue. As such, this author submits that basic research occupies a unique and lucrative niche driving clinical applications. PMID:22737057

  17. Anthrax - Multiple Languages: MedlinePlus

    MedlinePlus

    ... Supplements Videos & Tools You Are Here: Home → Multiple Languages → All Health Topics → Anthrax URL of this page: https://www.nlm.nih.gov/medlineplus/languages/anthrax.html Other topics A-Z A B ...

  18. Anthrax Vaccine and Public Health Policy

    PubMed Central

    Weiss, Martin Meyer; Weiss, Peter D.; Weiss, Joseph B.

    2007-01-01

    The Centers for Disease Control and Prevention has classified Bacillus anthracis, the causative organism of anthrax, as a category A potential bioterrorism agent. There are critical shortcomings in the US anthrax vaccine program. Rather than depending on the private sector, the government must assume direct production of anthrax vaccine. The development of a capacity capable of preemptive immunization of the public against anthrax should be considered. PMID:17901434

  19. Anthrax: A Guide for Biology Teachers.

    ERIC Educational Resources Information Center

    Simon, Eric J.

    2002-01-01

    Presents facts about anthrax so that biology teachers can communicate them to others. Defines anthrax and the nature of bacterial spores. Discusses transmission and clinical presentation as well as prevention, diagnosis, and treatment. Explores the use of anthrax as a biological warfare agent. (Contains 27 references.) (DDR)

  20. Anthrax - Multiple Languages: MedlinePlus

    MedlinePlus

    ... Are Here: Home → Multiple Languages → All Health Topics → Anthrax URL of this page: https://medlineplus.gov/languages/anthrax.html Other topics A-Z A B C ... V W XYZ List of All Topics All Anthrax - Multiple Languages To use the sharing features on ...

  1. Neutralizing antibody and functional mapping of Bacillus anthracis protective antigen-The first step toward a rationally designed anthrax vaccine.

    PubMed

    McComb, Ryan C; Martchenko, Mikhail

    2016-01-01

    Anthrax is defined by the Centers for Disease Control and Prevention as a Category A pathogen for its potential use as a bioweapon. Current prevention treatments include Anthrax Vaccine Adsorbed (AVA). AVA is an undefined formulation of Bacillus anthracis culture supernatant adsorbed to aluminum hydroxide. It has an onerous vaccination schedule, is slow and cumbersome to produce and is slightly reactogenic. Next-generation vaccines are focused on producing recombinant forms of anthrax toxin in a well-defined formulation but these vaccines have been shown to lose potency as they are stored. In addition, studies have shown that a proportion of the antibody response against these vaccines is focused on non-functional, non-neutralizing regions of the anthrax toxin while some essential functional regions are shielded from eliciting an antibody response. Rational vaccinology is a developing field that focuses on designing vaccine antigens based on structural information provided by neutralizing antibody epitope mapping, crystal structure analysis, and functional mapping through amino acid mutations. This information provides an opportunity to design antigens that target only functionally important and conserved regions of a pathogen in order to make a more optimal vaccine product. This review provides an overview of the literature related to functional and neutralizing antibody epitope mapping of the Protective Antigen (PA) component of anthrax toxin. PMID:26611201

  2. Airing Out Anthrax

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The AiroCide TiO2 is an air-purifier that kills 93.3 percent of airborne pathogens that pass through it, including Bacillus anthraci, more commonly known as anthrax. It is essentially a spinoff of KES Science & Technology, Inc.'s Bio-KES system, a highly effective device used by the produce industry for ethylene gas removal to aid in preserving the freshness of fruits, vegetables, and flowers. The TiO2-based ethylene removal technology that is incorporated into the company's AiroCide TiO2 and Bio-KES products was first integrated into a pair of plant-growth chambers known as ASTROCULTURE(TM) and ADVANCED ASTROCULTURE(TM). Both chambers have housed commercial plant growth experiments in space on either the Space Shuttle or the International Space Station. The AiroCide TiO2 also has a proven record of destroying 98 percent of other airborne pathogens, such as microscopic dust mites, molds, and fungi. Moreover, the device is a verified killer of Influenza A (flu), E. coli, Staphylococcus aureas, Streptococcus pyogenes, and Mycoplasma pneumoniae, among many other harmful viruses.

  3. Anthrax protective antigen delivered by Salmonella enterica serovar Typhi Ty21a protects mice from a lethal anthrax spore challenge.

    PubMed

    Osorio, Manuel; Wu, Yanping; Singh, Sunil; Merkel, Tod J; Bhattacharyya, Siba; Blake, Milan S; Kopecko, Dennis J

    2009-04-01

    Bacillus anthracis, the etiological agent of anthrax disease, is a proven weapon of bioterrorism. Currently, the only licensed vaccine against anthrax in the United States is AVA Biothrax, which, although efficacious, suffers from several limitations. This vaccine requires six injectable doses over 18 months to stimulate protective immunity, requires a cold chain for storage, and in many cases has been associated with adverse effects. In this study, we modified the B. anthracis protective antigen (PA) gene for optimal expression and stability, linked it to an inducible promoter for maximal expression in the host, and fused it to the secretion signal of the Escherichia coli alpha-hemolysin protein (HlyA) on a low-copy-number plasmid. This plasmid was introduced into the licensed typhoid vaccine strain, Salmonella enterica serovar Typhi strain Ty21a, and was found to be genetically stable. Immunization of mice with three vaccine doses elicited a strong PA-specific serum immunoglobulin G response with a geometric mean titer of 30,000 (range, 5,800 to 157,000) and lethal-toxin-neutralizing titers greater than 16,000. Vaccinated mice demonstrated 100% protection against a lethal intranasal challenge with aerosolized spores of B. anthracis 7702. The ultimate goal is a temperature-stable, safe, oral human vaccine against anthrax infection that can be self-administered in a few doses over a short period of time. PMID:19179420

  4. Synthetic smoke with acrolein but not HCl produces pulmonary edema

    SciTech Connect

    Hales, C.A.; Barkin, P.W.; Jung, W.; Trautman, E.; Lamborghini, D.; Herrig, N.; Burke, J.

    1988-03-01

    The chemical toxins in smoke and not the heat are responsible for the pulmonary edema of smoke inhalation. We developed a synthetic smoke composed of carbon particles (mean diameter of 4.3 microns) to which toxins known to be in smoke, such as HCl or acrolein, could be added one at a time. We delivered synthetic smoke to dogs for 10 min and monitored extravascular lung water (EVLW) accumulation thereafter with a double-indicator thermodilution technique. Final EVLW correlated highly with gravimetric values (r = 0.93, P less than 0.01). HCl in concentrations of 0.1-6 N when added to heated carbon (120 degrees C) and cooled to 39 degrees C produced airway damage but no pulmonary edema. Acrolein, in contrast, produced airway damage but also pulmonary edema, whereas capillary wedge pressures remained stable. Low-dose acrolein smoke (less than 200 ppm) produced edema in two of five animals with a 2- to 4-h delay. Intermediate-dose acrolein smoke (200-300 ppm) always produced edema at an average of 147 +/- 57 min after smoke, whereas high-dose acrolein (greater than 300 ppm) produced edema at 65 +/- 16 min after smoke. Thus acrolein but not HCl, when presented as a synthetic smoke, produced a delayed-onset, noncardiogenic, and peribronchiolar edema in a roughly dose-dependent fashion.

  5. Synthetic smoke with acrolein but not HCl produces pulmonary edema.

    PubMed

    Hales, C A; Barkin, P W; Jung, W; Trautman, E; Lamborghini, D; Herrig, N; Burke, J

    1988-03-01

    The chemical toxins in smoke and not the heat are responsible for the pulmonary edema of smoke inhalation. We developed a synthetic smoke composed of carbon particles (mean diameter of 4.3 microns) to which toxins known to be in smoke, such as HCl or acrolein, could be added one at a time. We delivered synthetic smoke to dogs for 10 min and monitored extravascular lung water (EVLW) accumulation thereafter with a double-indicator thermodilution technique. Final EVLW correlated highly with gravimetric values (r = 0.93, P less than 0.01). HCl in concentrations of 0.1-6 N when added to heated carbon (120 degrees C) and cooled to 39 degrees C produced airway damage but no pulmonary edema. Acrolein, in contrast, produced airway damage but also pulmonary edema, whereas capillary wedge pressures remained stable. Low-dose acrolein smoke (less than 200 ppm) produced edema in two of five animals with a 2- to 4-h delay. Intermediate-dose acrolein smoke (200-300 ppm) always produced edema at an average of 147 +/- 57 min after smoke, whereas high-dose acrolein (greater than 300 ppm) produced edema at 65 +/- 16 min after smoke. Thus acrolein but not HCl, when presented as a synthetic smoke, produced a delayed-onset, noncardiogenic, and peribronchiolar edema in a roughly dose-dependent fashion. PMID:3284867

  6. Immunization with a Recombinant, Pseudomonas fluorescens-Expressed, Mutant Form of Bacillus anthracis-Derived Protective Antigen Protects Rabbits from Anthrax Infection

    PubMed Central

    Reed, Matthew D.; Wilder, Julie A.; Mega, William M.; Hutt, Julie A.; Kuehl, Philip J.; Valderas, Michelle W.; Chew, Lawrence L.; Liang, Bertrand C.; Squires, Charles H.

    2015-01-01

    Protective antigen (PA), one of the components of the anthrax toxin, is the major component of human anthrax vaccine (Biothrax). Human anthrax vaccines approved in the United States and Europe consist of an alum-adsorbed or precipitated (respectively) supernatant material derived from cultures of toxigenic, non-encapsulated strains of Bacillus anthracis. Approved vaccination schedules in humans with either of these vaccines requires several booster shots and occasionally causes adverse injection site reactions. Mutant derivatives of the protective antigen that will not form the anthrax toxins have been described. We have cloned and expressed both mutant (PA SNKE167-ΔFF-315-E308D) and native PA molecules recombinantly and purified them. In this study, both the mutant and native PA molecules, formulated with alum (Alhydrogel), elicited high titers of anthrax toxin neutralizing anti-PA antibodies in New Zealand White rabbits. Both mutant and native PA vaccine preparations protected rabbits from lethal, aerosolized, B. anthracis spore challenge subsequent to two immunizations at doses of less than 1 μg. PMID:26207820

  7. Immunization with a Recombinant, Pseudomonas fluorescens-Expressed, Mutant Form of Bacillus anthracis-Derived Protective Antigen Protects Rabbits from Anthrax Infection.

    PubMed

    Reed, Matthew D; Wilder, Julie A; Mega, William M; Hutt, Julie A; Kuehl, Philip J; Valderas, Michelle W; Chew, Lawrence L; Liang, Bertrand C; Squires, Charles H

    2015-01-01

    Protective antigen (PA), one of the components of the anthrax toxin, is the major component of human anthrax vaccine (Biothrax). Human anthrax vaccines approved in the United States and Europe consist of an alum-adsorbed or precipitated (respectively) supernatant material derived from cultures of toxigenic, non-encapsulated strains of Bacillus anthracis. Approved vaccination schedules in humans with either of these vaccines requires several booster shots and occasionally causes adverse injection site reactions. Mutant derivatives of the protective antigen that will not form the anthrax toxins have been described. We have cloned and expressed both mutant (PA SNKE167-ΔFF-315-E308D) and native PA molecules recombinantly and purified them. In this study, both the mutant and native PA molecules, formulated with alum (Alhydrogel), elicited high titers of anthrax toxin neutralizing anti-PA antibodies in New Zealand White rabbits. Both mutant and native PA vaccine preparations protected rabbits from lethal, aerosolized, B. anthracis spore challenge subsequent to two immunizations at doses of less than 1 μg. PMID:26207820

  8. Treatment of Anthrax Disease Frequently Asked Questions

    SciTech Connect

    Judd, Kathleen S.; Young, Joan E.; Lesperance, Ann M.; Malone, John D.

    2010-05-14

    This document provides a summary of Frequently Asked Questions (FAQs) on the treatment of anthrax disease caused by a wide-area release of Bacillus anthracis spores as an act bioterrorism. These FAQs are intended to provide the public health and medical community, as well as others, with guidance and communications to support the response and long-term recovery from an anthrax event.

  9. Anthrax vaccine associated deaths in miniature horses.

    PubMed

    Wobeser, Bruce K

    2015-04-01

    During a widespread anthrax outbreak in Canada, miniature horses were vaccinated using a live spore anthrax vaccine. Several of these horses died from an apparent immune-mediated vasculitis temporally associated with this vaccination. During the course of the outbreak, other miniature horses from different regions with a similar vaccination history, clinical signs, and necropsy findings were found. PMID:25829553

  10. ESCHERICHIA COLI O147: AN EMERGING SEROGROUP OF EDEMA DISEASE OUTBREAKS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Edema disease is a systemic disease of weanling pigs caused by E. coli strains that produce a variant of Shiga toxin, Stx2e. These strains usually produce F18ab fimbriae and heat stable enterotoxin b (STb). Historically, edema disease strains from U.S. outbreaks have not produced heat stable enter...

  11. Stable Dry Powder Formulation for Nasal Delivery of Anthrax Vaccine

    PubMed Central

    Wang, Sheena H.; Kirwan, Shaun M.; Abraham, Soman N.; Staats, Herman F.; Hickey, Anthony J.

    2013-01-01

    There is a current biodefense interest in protection against Anthrax. Here we developed a new generation of stable and effective anthrax vaccine. We studied the immune response elicited by rPA delivered intranasally with a novel mucosal adjuvant, a mast cell activator Compound 48/80. The vaccine formulation was prepared in a powder form by spray-freeze-drying (SFD) under optimized conditions to produce particles with a target size of D50=25μm, suitable for delivery to the rabbit nasal cavity. Physicochemical properties of the powder vaccines were characterized to assess their delivery and storage potential. Structural stability of rPA was confirmed by CD and ATR-FTIR, while functional stability of rPA and C48/80 was monitored by cell-based assays. Animal study was performed using a unitdose powder device for direct nasal application. Results showed that C48/80 provided effective mucosal adjuvant activity in rabbits. Freshly prepared SFD powder vaccine formulations or powders stored for over two years at room temperature elicited significantly elevated serum PA-specific and lethal toxin neutralization antibody titers that were comparable to that induced by IM immunization with rPA. Nasal delivery of this vaccine formulation may be a viable alternative to the currently licensed vaccine, or an attractive vaccine platform for other mucosally transmitted diseases. PMID:21905034

  12. Purification and biophysical characterization of the core protease domain of anthrax lethal factor

    SciTech Connect

    Gkazonis, Petros V.; Dalkas, Georgios A.; Chasapis, Christos T.; Vlamis-Gardikas, Alexios; Bentrop, Detlef; Spyroulias, Georgios A.

    2010-06-04

    Anthrax lethal toxin (LeTx) stands for the major virulence factor of the anthrax disease. It comprises a 90 kDa highly specific metalloprotease, the anthrax lethal factor (LF). LF possesses a catalytic Zn{sup 2+} binding site and is highly specific against MAPK kinases, thus representing the most potent native biomolecule to alter and inactivate MKK [MAPK (mitogen-activated protein kinase) kinases] signalling pathways. Given the importance of the interaction between LF and substrate for the development of anti-anthrax agents as well as the potential treatment of nascent tumours, the analysis of the structure and dynamic properties of the LF catalytic site are essential to elucidate its enzymatic properties. Here we report the recombinant expression and purification of a C-terminal part of LF (LF{sub 672-776}) that harbours the enzyme's core protease domain. The biophysical characterization and backbone assignments ({sup 1}H, {sup 13}C, {sup 15}N) of the polypeptide revealed a stable, well folded structure even in the absence of Zn{sup 2+}, suitable for high resolution structural analysis by NMR.

  13. Epsilon toxin: a fascinating pore-forming toxin.

    PubMed

    Popoff, Michel R

    2011-12-01

    Epsilon toxin (ETX) is produced by strains of Clostridium perfringens classified as type B or type D. ETX belongs to the heptameric β-pore-forming toxins including aerolysin and Clostridium septicum alpha toxin, which are characterized by the formation of a pore through the plasma membrane of eukaryotic cells consisting in a β-barrel of 14 amphipatic β strands. By contrast to aerolysin and C. septicum alpha toxin, ETX is a much more potent toxin and is responsible for enterotoxemia in animals, mainly sheep. ETX induces perivascular edema in various tissues and accumulates in particular in the kidneys and brain, where it causes edema and necrotic lesions. ETX is able to pass through the blood-brain barrier and stimulate the release of glutamate, which accounts for the symptoms of nervous excitation observed in animal enterotoxemia. At the cellular level, ETX causes rapid swelling followed by cell death involving necrosis. The precise mode of action of ETX remains to be determined. ETX is a powerful toxin, however, it also represents a unique tool with which to vehicle drugs into the central nervous system or target glutamatergic neurons. PMID:21535407

  14. Increased membrane turnover in the brain in cutaneous anthrax without central nervous system disorder: a magnetic resonance spectroscopy study.

    PubMed

    Bayindir, Yasar; Firat, Ahmet K; Kayabas, Uner; Alkan, Alpay; Yetkin, Funda; Karakas, Hakki M; Yologlu, Saim

    2012-07-01

    Cutaneous anthrax, caused by Bacillus anthracis contacting the skin, is the most common form of human anthrax. Recent studies implicate the presence of additional, possibly toxin-related subtle changes, even in patients without neurological or radiological findings. In this study, the presence of subtle changes in cutaneous anthrax was investigated at the metabolite level using magnetic resonance spectroscopy. Study subjects were consisted of 10 patients with cutaneous anthrax without co-morbid disease and/or neurological findings, and 13 healthy controls. There were no statistical differences in age and gender between two groups. The diagnosis of cutaneous anthrax was based on medical history, presence of a typical cutaneous lesion, large gram positive bacilli on gram staining and/or positive culture for B. anthracis from cutaneous samples. Brain magnetic resonance imaging examination consisted of conventional imaging and single-voxel magnetic resonance spectroscopy. Magnetic resonance spectroscopy was performed by using point-resolved spectroscopy sequence (TR: 2000ms, TE: 136ms, 128 averages). Voxels of 20mm×20mm×20mm were placed in normal-appearing parietal white matter to detect metabolite levels. Cerebral metabolite peaks were measured in normal appearing parietal white matter. N-acetyl aspartate/creatine and choline/creatine ratios were calculated using standard analytical procedures. Patients and controls were not statistically different regarding parietal white matter N-acetyl aspartate/creatine ratios (p=0.902), a finding that implicates the conservation of neuronal and axonal integrity and neuronal functions. However, choline/creatine ratios were significantly higher in patient groups (p=0.001), a finding implicating an increased membrane turnover. In conclusion, these two findings point to a possibly anthrax toxins-related subtle inflammatory reaction of the central nervous system at the cellular level. PMID:22543072

  15. A fragment of anthrax lethal factor delivers proteins to the cytosol without requiring protective antigen

    PubMed Central

    Kushner, Nicholas; Zhang, Dong; Touzjian, Neal; Essex, Max; Lieberman, Judy; Lu, Yichen

    2003-01-01

    Anthrax protective antigen (PA) is a 735-aa polypeptide that facilitates the exit of anthrax lethal factor (LF) from the endosome to the cytosol where the toxin acts. We recently found, however, that a fusion protein of the detoxified N-terminal domain of lethal factor (LFn) with a foreign peptide could induce CD8 T cell immune responses in the absence of PA. Because CD8 T cells recognize peptides derived from proteins degraded in the cytosol, this result suggests that lethal factor may be capable of entering the cytosol independently of PA. To investigate this further, the intracellular trafficking of an LFn-enhanced green fluorescent protein fusion protein (LFn-GFP) in the presence or absence of PA was examined by using confocal microscopy. LFn-GFP is able to enter the cytosol without PA. Moreover, it efficiently colocalizes with the proteosome 20s subunit, which degrades proteins into peptides for presentation to CD8 T cells by the MHC class I pathway. We further demonstrate that in the presence of an immune adjuvant LFn fusion protein without PA is able to effectively elicit anti-HIV cytotoxic T lymphocyte in inbred mice. These results indicate that LFn may be used without PA in a protein vaccine as a carrier to deliver antigens into the cytosol for efficient induction of T lymphocyte responses. Furthermore, these results enable us to propose a modified molecular mechanism of anthrax lethal toxin. PMID:12740437

  16. Targeting HER2-positive cancer cells with receptor-redirected anthrax protective antigen

    PubMed Central

    McCluskey, Andrew J.; Olive, Andrew J.; Starnbach, Michael N.; Collier, R. John

    2012-01-01

    Targeted therapeutics have emerged in recent years as an attractive approach to treating various types of cancer. One approach is to modify a cytocidal protein toxin to direct its action to a specific population of cancer cells. We created a targeted toxin in which the receptor-binding and pore-forming moiety of anthrax toxin, termed Protective Antigen (PA), was modified to redirect its receptor specificity to HER2, a marker expressed at the surface of a significant fraction of breast and ovarian tumors. The resulting fusion protein (mPA-ZHER2) delivered cytocidal effectors specifically into HER2-positive tumor cells, including a trastuzumab-resistant line, causing death of the cells. No off-target killing of HER2-negative cells was observed, either with homogeneous populations or with mixtures of HER2-positive and HER2-negative cells. A mixture of mPA variants targeting different receptors mediated killing of cells bearing either receptor, without affecting cells devoid of these receptors. Anthrax toxin may serve as an effective platform for developing therapeutics to ablate cells bearing HER2 or other tumor-specific cell-surface markers. PMID:23290417

  17. Role of Visible Light-Activated Photocatalyst on the Reduction of Anthrax Spore-Induced Mortality in Mice

    PubMed Central

    Huang, Hsin-Hsien; Wong, Ming-Show; Lin, Hung-Chi; Chang, Hsin-Hou

    2009-01-01

    Background Photocatalysis of titanium dioxide (TiO2) substrates is primarily induced by ultraviolet light irradiation. Anion-doped TiO2 substrates were shown to exhibit photocatalytic activities under visible-light illumination, relative environmentally-friendly materials. Their anti-spore activity against Bacillus anthracis, however, remains to be investigated. We evaluated these visible-light activated photocatalysts on the reduction of anthrax spore-induced pathogenesis. Methodology/Principal Findings Standard plating method was used to determine the inactivation of anthrax spore by visible light-induced photocatalysis. Mouse models were further employed to investigate the suppressive effects of the photocatalysis on anthrax toxin- and spore-mediated mortality. We found that anti-spore activities of visible light illuminated nitrogen- or carbon-doped titania thin films significantly reduced viability of anthrax spores. Even though the spore-killing efficiency is only approximately 25%, our data indicate that spores from photocatalyzed groups but not untreated groups have a less survival rate after macrophage clearance. In addition, the photocatalysis could directly inactivate lethal toxin, the major virulence factor of B. anthracis. In agreement with these results, we found that the photocatalyzed spores have tenfold less potency to induce mortality in mice. These data suggest that the photocatalysis might injury the spores through inactivating spore components. Conclusion/Significance Photocatalysis induced injuries of the spores might be more important than direct killing of spores to reduce pathogenicity in the host. PMID:19132100

  18. Small Molecule Inhibitors of Anthrax Lethal Factor Toxin

    PubMed Central

    Williams, John D.; Khan, Atiyya R.; Cardinale, Steven C.; Butler, Michelle M.; Bowlin, Terry L.; Peet, Norton P.

    2014-01-01

    This manuscript describes the preparation of new small molecule inhibitors of Bacillus anthracis lethal factor. Our starting point was the symmetrical, bis-quinolinyl compound 1 (NSC 12155). Optimization of one half of this molecule led to new LF inhibitors that were desymmetrized to afford more drug-like compounds. PMID:24290062

  19. Advances in Anthrax Detection: Overview of Bioprobes and Biosensors.

    PubMed

    Kim, Joungmok; Gedi, Vinayakumar; Lee, Sang-Choon; Cho, Jun-Haeng; Moon, Ji-Young; Yoon, Moon-Young

    2015-06-01

    Anthrax is an infectious disease caused by Bacillus anthracis. Although anthrax commonly affects domestic and wild animals, it causes a rare but lethal infection in humans. A variety of techniques have been introduced and evaluated to detect anthrax using cultures, polymerase chain reaction, and immunoassays to address the potential threat of anthrax being used as a bioweapon. The high-potential harm of anthrax in bioterrorism requires sensitive and specific detection systems that are rapid, field-ready, and real-time monitoring. Here, we provide a systematic overview of anthrax detection probes with their potential applications in various ultra-sensitive diagnostic systems. PMID:25987133

  20. List of Contractors to Support Anthrax Remediation

    SciTech Connect

    Judd, Kathleen S.; Lesperance, Ann M.

    2010-05-14

    This document responds to a need identified by private sector businesses for information on contractors that may be qualified to support building remediation efforts following a wide-area anthrax release.

  1. Laboratories Face Crackdown in Wake of Anthrax Scare.

    ERIC Educational Resources Information Center

    Southwick, Ron

    2001-01-01

    Explores the after-effects on college laboratories of the anthrax mail scare; scientists say the anthrax scare justifies tougher rules on biological agents, but some fear that Congress may go too far. (EV)

  2. Latest advances in edema

    NASA Technical Reports Server (NTRS)

    Villavicencio, J. L.; Hargens, A. R.; Pikoulicz, E.

    1996-01-01

    Basic concepts in the physiopathology of edema are reviewed. The mechanisms of fluid exchange across the capillary endothelium are explained. Interstitial flow and lymph formation are examined. Clinical disorders of tissue and lymphatic transport, microcirculatory derangements in venous disorders, protein disorders, and lymphatic system disorders are explored. Techniques for investigational imaging of the lymphatic system are explained.

  3. Micromechanics of alveolar edema.

    PubMed

    Perlman, Carrie E; Lederer, David J; Bhattacharya, Jahar

    2011-01-01

    The decrease of lung compliance in pulmonary edema underlies ventilator-induced lung injury. However, the cause of the decrease in compliance is unknown. We tested the hypothesis that in pulmonary edema, the mechanical effects of liquid-filled alveoli increase tissue stress in adjacent air-filled alveoli. By micropuncture of isolated, perfused rat lungs, we established a single-alveolus model of pulmonary edema that we imaged using confocal microscopy. In this model, we viewed a liquid-filled alveolus together with its air-filled neighbor at different transpulmonary pressures, both before and after liquid-filling. Instilling liquid in an alveolus caused alveolar shrinkage. As a result, the interalveolar septum was stretched, causing the neighboring air-filled alveolus to bulge. Thus, the air-filled alveolus was overexpanded by virtue of its adjacency to a liquid-filled alveolus. Confocal microscopy at different depths of the liquid-filled alveolus revealed a meniscus. Lung inflation to near-total lung capacity (TLC) demonstrated decreased compliance of the air-filled but not liquid-filled alveolus. However, at near TLC, the air-filled alveolus was larger than it was in the pre-edematous control tissue. In pulmonary edema, liquid-filled alveoli induce mechanical stress on air-filled alveoli, reducing the compliance of air-filled alveoli, and hence overall lung compliance. Because of increased mechanical stress, air-filled alveoli may be susceptible to overdistension injury during mechanical ventilation of the edematous lung. PMID:20118224

  4. Anthrax

    MedlinePlus

    ... by the bacterium Bacillus anthracis , which lives in soil. The bacterial cell lives as a hardy spore ... Bacillus anthracis is a bacterium that lives in soil and has developed a survival tactic that allows ...

  5. Discovery of Mouse Spleen Signaling Responses to Anthrax using Label-Free Quantitative Phosphoproteomics via Mass Spectrometry*

    PubMed Central

    Manes, Nathan P.; Dong, Li; Zhou, Weidong; Du, Xiuxia; Reghu, Nikitha; Kool, Arjan C.; Choi, Dahan; Bailey, Charles L.; Petricoin, Emanuel F.; Liotta, Lance A.; Popov, Serguei G.

    2011-01-01

    Inhalational anthrax is caused by spores of the bacterium Bacillus anthracis (B. anthracis), and is an extremely dangerous disease that can kill unvaccinated victims within 2 weeks. Modern antibiotic-based therapy can increase the survival rate to ∼50%, but only if administered presymptomatically (within 24–48 h of exposure). To discover host signaling responses to presymptomatic anthrax, label-free quantitative phosphoproteomics via liquid chromatography coupled to mass spectrometry was used to compare spleens from uninfected and spore-challenged mice over a 72 h time-course. Spleen proteins were denatured using urea, reduced using dithiothreitol, alkylated using iodoacetamide, and digested into peptides using trypsin, and the resulting phosphopeptides were enriched using titanium dioxide solid-phase extraction and analyzed by nano-liquid chromatography-Linear Trap Quadrupole-Orbitrap-MS(/MS). The fragment ion spectra were processed using DeconMSn and searched using both Mascot and SEQUEST resulting in 252,626 confident identifications of 6248 phosphopeptides (corresponding to 5782 phosphorylation sites). The precursor ion spectra were deisotoped using Decon2LS and aligned using MultiAlign resulting in the confident quantitation of 3265 of the identified phosphopeptides. ANOVAs were used to produce a q-value ranked list of host signaling responses. Late-stage (48–72 h postchallenge) Sterne strain (lethal) infections resulted in global alterations to the spleen phosphoproteome. In contrast, ΔSterne strain (asymptomatic; missing the anthrax toxin) infections resulted in 188 (5.8%) significantly altered (q<0.05) phosphopeptides. Twenty-six highly tentative phosphorylation responses to early-stage (24 h postchallenge) anthrax were discovered (q<0.5), and ten of these originated from eight proteins that have known roles in the host immune response. These tentative early-anthrax host response signaling events within mouse spleens may translate into presymptomatic

  6. Effects of 39 Compounds on Calmodulin-Regulated Adenylyl Cyclases AC1 and Bacillus anthracis Edema Factor

    PubMed Central

    Lübker, Carolin; Seifert, Roland

    2015-01-01

    Adenylyl cyclases (ACs) catalyze the conversion of ATP into the second messenger cAMP. Membranous AC1 (AC1) is involved in processes of memory and learning and in muscle pain. The AC toxin edema factor (EF) of Bacillus anthracis is involved in the development of anthrax. Both ACs are stimulated by the eukaryotic Ca2+-sensor calmodulin (CaM). The CaM-AC interaction could constitute a potential target to enhance or impair the AC activity of AC1 and EF to intervene in above (patho)physiological mechanisms. Thus, we analyzed the impact of 39 compounds including typical CaM-inhibitors, an anticonvulsant, an anticholinergic, antidepressants, antipsychotics and Ca2+-antagonists on CaM-stimulated catalytic activity of AC1 and EF. Compounds were tested at 10 μM, i.e., a concentration that can be reached therapeutically for certain antidepressants and antipsychotics. Calmidazolium chloride decreased CaM-stimulated AC1 activity moderately by about 30%. In contrast, CaM-stimulated EF activity was abrogated by calmidazolium chloride and additionally decreased by chlorpromazine, felodipine, penfluridol and trifluoperazine by about 20–40%. The activity of both ACs was decreased by calmidazolium chloride in the presence and absence of CaM. Thus, CaM-stimulated AC1 activity is more insensitive to inhibition by small molecules than CaM-stimulated EF activity. Inhibition of AC1 and EF by calmidazolium chloride is largely mediated via a CaM-independent allosteric mechanism. PMID:25946093

  7. Generation and Characterization of Human Monoclonal Antibodies Targeting Anthrax Protective Antigen following Vaccination with a Recombinant Protective Antigen Vaccine

    PubMed Central

    Chi, Xiangyang; Li, Jianmin; Liu, Weicen; Wang, Xiaolin; Yin, Kexin; Liu, Ju; Zai, Xiaodong; Li, Liangliang; Song, Xiaohong; Zhang, Jun; Zhang, Xiaopeng; Yin, Ying; Fu, Ling; Xu, Junjie

    2015-01-01

    The anthrax protective antigen (PA) is the central component of the three-part anthrax toxin, and it is the primary immunogenic component in the approved AVA anthrax vaccine and the “next-generation” recombinant PA (rPA) anthrax vaccines. Animal models have indicated that PA-specific antibodies (AB) are sufficient to protect against infection with Bacillus anthracis. In this study, we investigated the PA domain specificity, affinity, mechanisms of neutralization, and synergistic effects of PA-specific antibodies from a single donor following vaccination with the rPA vaccine. Antibody-secreting cells were isolated 7 days after the donor received a boost vaccination, and 34 fully human monoclonal antibodies (hMAb) were identified. Clones 8H6, 4A3, and 22F1 were able to neutralize lethal toxin (LeTx) both in vitro and in vivo. Clone 8H6 neutralized LeTx by preventing furin cleavage of PA in a dose-dependent manner. Clone 4A3 enhanced degradation of nicked PA, thereby interfering with PA oligomerization. The mechanism of 22F1 is still unclear. A fourth clone, 2A6, that was protective only in vitro was found to be neutralizing in vivo in combination with a toxin-enhancing antibody, 8A7, which binds to domain 3 of PA and PA oligomers. These results provide novel insights into the antibody response elicited by the rPA vaccine and may be useful for PA-based vaccine and immunotherapeutic cocktail design. PMID:25787135

  8. Generation and Characterization of Human Monoclonal Antibodies Targeting Anthrax Protective Antigen following Vaccination with a Recombinant Protective Antigen Vaccine.

    PubMed

    Chi, Xiangyang; Li, Jianmin; Liu, Weicen; Wang, Xiaolin; Yin, Kexin; Liu, Ju; Zai, Xiaodong; Li, Liangliang; Song, Xiaohong; Zhang, Jun; Zhang, Xiaopeng; Yin, Ying; Fu, Ling; Xu, Junjie; Yu, Changming; Chen, Wei

    2015-05-01

    The anthrax protective antigen (PA) is the central component of the three-part anthrax toxin, and it is the primary immunogenic component in the approved AVA anthrax vaccine and the "next-generation" recombinant PA (rPA) anthrax vaccines. Animal models have indicated that PA-specific antibodies (AB) are sufficient to protect against infection with Bacillus anthracis. In this study, we investigated the PA domain specificity, affinity, mechanisms of neutralization, and synergistic effects of PA-specific antibodies from a single donor following vaccination with the rPA vaccine. Antibody-secreting cells were isolated 7 days after the donor received a boost vaccination, and 34 fully human monoclonal antibodies (hMAb) were identified. Clones 8H6, 4A3, and 22F1 were able to neutralize lethal toxin (LeTx) both in vitro and in vivo. Clone 8H6 neutralized LeTx by preventing furin cleavage of PA in a dose-dependent manner. Clone 4A3 enhanced degradation of nicked PA, thereby interfering with PA oligomerization. The mechanism of 22F1 is still unclear. A fourth clone, 2A6, that was protective only in vitro was found to be neutralizing in vivo in combination with a toxin-enhancing antibody, 8A7, which binds to domain 3 of PA and PA oligomers. These results provide novel insights into the antibody response elicited by the rPA vaccine and may be useful for PA-based vaccine and immunotherapeutic cocktail design. PMID:25787135

  9. A Novel Chimeric Anti-PA Neutralizing Antibody for Postexposure Prophylaxis and Treatment of Anthrax

    PubMed Central

    Xiong, Siping; Tang, Qi; Liang, Xudong; Zhou, Tingting; Yang, Jin; Liu, Peng; Chen, Ya; Wang, Changjun; Feng, Zhenqing; Zhu, Jin

    2015-01-01

    Anthrax is a highly lethal infectious disease caused by the bacterium Bacillus anthracis, and the associated shock is closely related to the lethal toxin (LeTx) produced by the bacterium. The central role played by the 63 kDa protective antigen (PA63) region of LeTx in the pathophysiology of anthrax makes it an excellent therapeutic target. In the present study, a human/murine chimeric IgG mAb, hmPA6, was developed by inserting murine antibody variable regions into human constant regions using antibody engineering technology. hmPA6 expressed in 293F cells could neutralize LeTx both in vitro and in vivo. At a dose of 0.3 mg/kg, it could protect all tested rats from a lethal dose of LeTx. Even administration of 0.6 mg/kg hmPA6 48 h before LeTx challenge protected all tested rats. The results indicate that hmPA6 is a potential candidate for clinical application in anthrax treatment. PMID:26134518

  10. Toxin-Independent Virulence of Bacillus anthracis in Rabbits

    PubMed Central

    Levy, Haim; Glinert, Itai; Weiss, Shay; Sittner, Assa; Schlomovitz, Josef; Altboum, Zeev; Kobiler, David

    2014-01-01

    The accepted paradigm states that anthrax is both an invasive and toxinogenic disease and that the toxins play a major role in pathogenicity. In the guinea pig (GP) model we have previously shown that deletion of all three toxin components results in a relatively moderate attenuation in virulence, indicating that B. anthracis possesses an additional toxin-independent virulence mechanism. To characterize this toxin-independent mechanism in anthrax disease, we developed a new rabbit model by intravenous injection (IV) of B. anthracis encapsulated vegetative cells, artificially creating bacteremia. Using this model we were able to demonstrate that also in rabbits, B. anthracis mutants lacking the toxins are capable of killing the host within 24 hours. This virulent trait depends on the activity of AtxA in the presence of pXO2, as, in the absence of the toxin genes, deletion of either component abolishes virulence. Furthermore, this IV virulence depends mainly on AtxA rather than the whole pXO1. A similar pattern was shown in the GP model using subcutaneous (SC) administration of spores of the mutant strains, demonstrating the generality of the phenomenon. The virulent strains showed higher bacteremia levels and more efficient tissue dissemination; however our interpretation is that tissue dissemination per se is not the main determinant of virulence whose exact nature requires further elucidation. PMID:24416317

  11. Mass spectrometric detection of protein-based toxins.

    PubMed

    Tevell Åberg, Annica; Björnstad, Kristian; Hedeland, Mikael

    2013-09-01

    This review focuses on mass spectrometric detection of protein-based toxins, which are among the most toxic substances known. Special emphasis is given to the bacterial toxins botulinum neurotoxin from Clostridium botulinum and anthrax toxins from Bacillus anthracis as well as the plant toxin ricin produced by Ricinus communis. A common feature, apart from their extreme toxicity, is that they are composed of 2 polypeptide chains, one of which is responsible for cell uptake and another that has enzymatic function with the ability to destroy basic cellular functions. These toxins pose a threat, both regarding natural spread and from a terrorism perspective. In order for public health and emergency response officials to take appropriate action in case of an outbreak, whether natural or intentional, there is a need for fast and reliable detection methods. Traditionally, large molecules like proteins have been detected using immunological techniques. Although sensitive, these methods suffer from some drawbacks, such as the risk of false-positives due to cross-reactions and detection of inactive toxin. This article describes recently developed instrumental methods based on mass spectrometry for the reliable detection of botulinum neurotoxins, anthrax toxins, and ricin. Unequivocal identification of a protein toxin can be carried out by mass spectrometry-based amino acid sequencing. Furthermore, in combination with antibody affinity preconcentration and biochemical tests with mass spectrometric detection demonstrating the toxin's enzymatic activity, very powerful analytical methods have been described. In conclusion, the advent of sensitive, easily operated mass spectrometers provides new possibilities for the detection of protein-based toxins. PMID:23971809

  12. When bioterrorism strikes: diagnosis and management of inhalational anthrax.

    PubMed

    Shafazand, Shirin

    2003-09-01

    In October and November, 2001, reports of patients with inhalational anthrax reacquainted the public with this ancient disease and introduced the harsh reality of a bioterrorist act. Bacillus anthracis, a rod-shaped, spore-forming bacterium, primarily infects herbivores. Humans traditionally have acquired the disease from occupational or agricultural exposure to infected animals and animal products. Recent events saw the intentional release of anthrax spores, using the U.S. postal system as an unlikely and unwilling agent. Cutaneous disease, pulmonary disease, and gastrointestinal anthrax are the known clinical manifestations of anthrax. Inhalational anthrax has the highest mortality and is the main focus of this report. PMID:14505276

  13. [Selected research problems of anthrax vaccine development].

    PubMed

    Zakowska, Dorota; Kocik, Janusz; Bartoszcze, Michał

    2009-01-01

    The threat of bioterrorism with B. anthracis against civilian population is one of major concern. After successful bioterroristic attack in 2001 in US renewed research interest has prompted in the development of new and more effective vaccine against anthrax. There are two licensed vaccines against anthrax--AVA-Bio-Thrax US and UK--sterile culture filtrate prepared by alum precipitation. Both vaccines are based on PA antigen. There are several concerns regarding PA based vaccines. They require six sc injections and yearly booster, high rates of local reaction after vaccination is observed, the immunity is not long lasting, vaccination do not protect animals against different strains of B. anthracis. New strategies in the development of anthrax vaccines have been presented (recombinant PA, subunits vaccine, mutants, conjugated). Using proteomic approaches new antigens have been also identified as candidates for future vaccines. More effective and easy to perform methods of vaccination have been reviewed. PMID:20120948

  14. Anthrax as the cause of preseptal cellulitis.

    PubMed

    Celebi, S; Celebi, H; Celiker, U O; Kandemir, B; Alagöz, G; Esmerligil, S

    1997-08-01

    Anthrax is an infectious disease caused by Bacillus anthracis. It is primarily a disease of domestic animals such as cattle, goats, and sheep; but humans can rarely be infected by contact with infected animals or contaminated animal products. Our case is a 4-year-old boy who was initially diagnosed as preseptal cellulitis, but later he showed the characteristic anthrax lesions with a black necrotic eschar. Scrapings from the necrotic tissue showed gram positive rods and culture grew Bacillus anthracis. The patient responded to intravenous administration of penicillin G, and the lesions resolved, leaving a scar on the right upper eyelid. Eyelid involvement of anthrax is rarely seen in clinical practice, but should be considered in differential diagnosis. PMID:9374261

  15. Diagnostic performance characteristics of a rapid field test for anthrax in cattle.

    PubMed

    Muller, Janine; Gwozdz, Jacek; Hodgeman, Rachel; Ainsworth, Catherine; Kluver, Patrick; Czarnecki, Jill; Warner, Simone; Fegan, Mark

    2015-07-01

    Although diagnosis of anthrax can be made in the field with a peripheral blood smear, and in the laboratory with bacterial culture or molecular based tests, these tests require either considerable experience or specialised equipment. Here we report on the evaluation of the diagnostic sensitivity and specificity of a simple and rapid in-field diagnostic test for anthrax, the anthrax immunochromatographic test (AICT). The AICT detects the protective antigen (PA) component of the anthrax toxin present within the blood of an animal that has died from anthrax. The test provides a result in 15min and offers the advantage of avoiding the necessity for on-site necropsy and subsequent occupational risks and environmental contamination. The specificity of the test was determined by testing samples taken from 622 animals, not infected with Bacillus anthracis. Diagnostic sensitivity was estimated on samples taken from 58 animals, naturally infected with B. anthracis collected over a 10-year period. All samples used to estimate the diagnostic sensitivity and specificity of the AICT were also tested using the gold standard of bacterial culture. The diagnostic specificity of the test was estimated to be 100% (99.4-100%; 95% CI) and the diagnostic sensitivity was estimated to be 93.1% (83.3-98.1%; 95% CI) (Clopper-Pearson method). Four samples produced false negative AICT results. These were among 9 samples, all of which tested positive for B. anthracis by culture, where there was a time delay between collection and testing of >48h and/or the samples were collected from animals that were >48h post-mortem. A statistically significant difference (P<0.001; Fishers exact test) was found between the ability of the AICT to detect PA in samples from culture positive animals <48h post-mortem, 49 of 49, Se=100% (92.8-100%; 95% CI) compared with samples tested >48h post-mortem 5 of 9 Se=56% (21-86.3%; 95% CI) (Clopper-Pearson method). Based upon these results a post hoc cut-off for use of

  16. A synthetic peptide vaccine directed against the 2ß2-2ß3 loop of domain 2 of protective antigen protects rabbits from inhalation anthrax.

    PubMed

    Oscherwitz, Jon; Yu, Fen; Cease, Kemp B

    2010-09-15

    The current vaccines for anthrax in the United States and United Kingdom are efficacious in the two most accepted animal models of inhalation anthrax, nonhuman primates and rabbits, but require extensive immunization protocols. We previously demonstrated that a linear determinant in domain 2 of Bacillus anthracis protective Ag (PA) is a potentially important target for an epitope-specific vaccine for anthrax, as Abs specific for this site, referred to as the loop-neutralizing determinant (LND), neutralize lethal toxin in vitro, yet are virtually absent in PA-immunized rabbits. In this study, we evaluated the immunogenicity and protective efficacy in rabbits of multiple antigenic peptides (MAPs) consisting of aa 304-319 from the LND of PA colinearly synthesized at the C terminus (T-B MAP) or N terminus (B-T MAP) with a heterologous T cell epitope from Plasmodium falciparum. Immunogenicity studies demonstrated that both MAPs elicited toxin-neutralizing Ab in rabbits. To evaluate the MAPs as potential anthrax vaccines, we immunized groups of rabbits (n = 7) with each MAP in Freund's adjuvant and then exposed all rabbits to a 200-LD(50) challenge with aerosolized spores of B. anthracis Ames strain. All seven rabbits immunized with the B-T MAP and 89% (six of seven) of rabbits immunized with the T-B MAP survived the spore challenge. Corollary studies with reference sera from human vaccinees immunized with rPA or anthrax vaccine absorbed and nonhuman primates immunized with PA revealed no detectable Ab with specificity for the LND. We conclude that a synthetic peptide vaccine targeting the LND would be a potentially efficacious vaccine for anthrax. PMID:20696862

  17. [Recombinant antibodies for medical protection against bioterrorism agents: the example of anthrax].

    PubMed

    Thullier, Philippe; Pelat, Thibault; Paucod, Jean-Charles; Vidal, Dominique

    2010-01-01

    Recombinant antibodies are a highly successful class of therapeutic molecules, they are well adapted for use against bio-weapons (BW) as they act immediately, are often synergistic with other therapeutic molecules, have a long half-life and are well tolerated. Anthrax is regarded at high risk of being used as BW, and its pathogenic properties depend on toxins, which might be neutralized by antibodies. These toxins are made of three different types of sub-units (PA, LF, EF). Several anti-PA have been developed, including an original approach by our team. We have developed an anti-LF, as recommended by experts. Our anti-PA antibody, and to a lesser extend our anti-LF antibody, will be presented here. PMID:20950579

  18. Toxin-induced resistance in Bacillus anthracis lethal toxin-treated macrophages

    PubMed Central

    Salles, Isabelle I.; Tucker, Amy E.; Voth, Daniel E.; Ballard, Jimmy D.

    2003-01-01

    In the current study, we show that macrophages adaptively resist anthrax lethal toxin (LT) through a toxin-activated process termed toxin-induced resistance (TIR). TIR was triggered by pretreatment of RAW 264.7 or J774A.1 macrophages with a low dose of LT for at least 6 h, which resulted in resistance to high doses of LT for 96 h. Activation of TIR required functional toxin, because LT subunits, mutants, and heat-inactivated toxin were unable to trigger resistance. TIR macrophages were not altered in toxin receptor levels or cell cycle profiles. Treatment of TIR macrophages with high doses of LT resulted in a sustained decline in full-length mitogen-activated protein kinase kinase 2, a known target of lethal factor, and a marked reduction in diphosphorylated extracellular response kinases 1,2 for 24 h. However, despite the sustained loss of full-length mitogen-activated protein kinase kinase 2, by 48 h, TIR macrophages regained diphosphorylated extracellular response kinases 1,2, suggesting an adaptation led to recovery of this signaling pathway. TIR macrophages were also able to maintain normal levels of ubiquitinylated proteins, whereas sensitive cells show a rapid reduction in ubiquitin-modified proteins before cell death, indicating a possible alteration in proteasome activity contributed to resistance. These results provide a paradigm for toxin-cell interactions and suggest macrophages are capable of adapting to and tolerating toxic doses of LT. PMID:14519843

  19. Diabetic Macular Edema

    NASA Astrophysics Data System (ADS)

    Lobo, Conceição; Pires, Isabel; Cunha-Vaz, José

    The optical coherence tomography (OCT), a noninvasive and noncontact diagnostic method, was introduced in 1995 for imaging macular diseases. In diabetic macular edema (DME), OCT scans show hyporeflectivity, due to intraretinal and/or subretinal fluid accumulation, related to inner and/or outer blood-retinal barrier breakdown. OCT tomograms may also reveal the presence of hard exudates, as hyperreflective spots with a shadow, in the outer retinal layers, among others. In conclusion, OCT is a particularly valuable diagnostic tool in DME, helpful both in the diagnosis and follow-up procedure.

  20. Efficacy of ETI-204 Monoclonal Antibody as an Adjunct Therapy in a New Zealand White Rabbit Partial Survival Model for Inhalational Anthrax

    PubMed Central

    Biron, Bethany; Beck, Katie; Dyer, David; Mattix, Marc; Twenhafel, Nancy

    2015-01-01

    Inhalational anthrax is characterized by extensive bacteremia and toxemia as well as nonspecific to mild flu-like symptoms, until the onset of hypotension, shock, and mortality. Without treatment, the mortality rate approaches 100%. Antibiotic treatment is not always effective, and alternative treatments are needed, such as monotherapy for antibiotic-resistant inhalational anthrax or as an adjunct therapy in combination with antibiotics. The Bacillus anthracis antitoxin monoclonal antibody (MAb) ETI-204 is a high-affinity chimeric deimmunized antibody which targets the anthrax toxin protective antigen (PA). In this study, a partial protection New Zealand White (NZW) rabbit model was used to evaluate the protective efficacy of the adjunct therapy with the MAb. Following detection of PA in the blood, NZW rabbits were administered either an antibiotic (doxycycline) alone or the antibiotic in conjunction with ETI-204. Survival was evaluated to compare the efficacy of the combination adjunct therapy with that of an antibiotic alone in treating inhalational anthrax. Overall, the results from this study indicate that a subtherapeutic regimen consisting of an antibiotic in combination with an anti-PA MAb results in increased survival compared to the antibiotic alone and would provide an effective therapeutic strategy against symptomatic anthrax in nonvaccinated individuals. PMID:25645849

  1. Involvement of the pagR gene of pXO2 in anthrax pathogenesis

    PubMed Central

    Liang, Xudong; Zhang, Enmin; Zhang, Huijuan; Wei, Jianchun; Li, Wei; Zhu, Jin; Wang, Bingxiang; Dong, Shulin

    2016-01-01

    Anthrax is a disease caused by Bacillus anthracis. Specifically, the anthrax toxins and capsules encoded by the pXO1 and pXO2 plasmids, respectively, are the major virulence factors. We previously reported that the pXO1 plasmid was retained in the attenuated strain of B. anthracis vaccine strains even after subculturing at high temperatures. In the present study, we reinvestigate the attenuation mechanism of Pasteur II. Sequencing of pXO1 and pXO2 from Pasteur II strain revealed mutations in these plasmids as compared to the reference sequences. Two deletions on these plasmids, one each on pXO1 and pXO2, were confirmed to be unique to the Pasteur II strain as compared to the wild-type strains. Gene replacement with homologous recombination revealed that the mutation in the promoter region of the pagR gene on pXO2, but not the mutation on pXO1, contributes to lethal levels of toxin production. This result was further confirmed by RT-PCR, western blot, and animal toxicity assays. Taken together, our results signify that the attenuation of the Pasteur II vaccine strain is caused by a mutation in the pagR gene on its pXO2 plasmid. Moreover, these data suggest that pXO2 plasmid encoded proteins are involved in the virulence of B. anthracis. PMID:27363681

  2. Substrate Recognition of Anthrax Lethal Factor Examined by Combinatorial and Pre-steady-state Kinetic Approaches*

    PubMed Central

    Zakharova, Maria Yu.; Kuznetsov, Nikita A.; Dubiley, Svetlana A.; Kozyr, Arina V.; Fedorova, Olga S.; Chudakov, Dmitry M.; Knorre, Dmitry G.; Shemyakin, Igor G.; Gabibov, Alexander G.; Kolesnikov, Alexander V.

    2009-01-01

    Lethal factor (LF), a zinc-dependent protease of high specificity produced by Bacillus anthracis, is the effector component of the binary toxin that causes death in anthrax. New therapeutics targeting the toxin are required to reduce systemic anthrax-related fatalities. In particular, new insights into the LF catalytic mechanism will be useful for the development of LF inhibitors. We evaluated the minimal length required for formation of bona fide LF substrates using substrate phage display. Phage-based selection yielded a substrate that is cleaved seven times more efficiently by LF than the peptide targeted in the protein kinase MKK6. Site-directed mutagenesis within the metal-binding site in the LF active center and within phage-selected substrates revealed a complex pattern of LF-substrate interactions. The elementary steps of LF-mediated proteolysis were resolved by the stopped-flow technique. Pre-steady-state kinetics of LF proteolysis followed a four-step mechanism as follows: initial substrate binding, rearrangement of the enzyme-substrate complex, a rate-limiting cleavage step, and product release. Examination of LF interactions with metal ions revealed an unexpected activation of the protease by Ca2+ and Mn2+. Based on the available structural and kinetic data, we propose a model for LF-substrate interaction. Resolution of the kinetic and structural parameters governing LF activity may be exploited to design new LF inhibitors. PMID:19359249

  3. Involvement of the pagR gene of pXO2 in anthrax pathogenesis.

    PubMed

    Liang, Xudong; Zhang, Enmin; Zhang, Huijuan; Wei, Jianchun; Li, Wei; Zhu, Jin; Wang, Bingxiang; Dong, Shulin

    2016-01-01

    Anthrax is a disease caused by Bacillus anthracis. Specifically, the anthrax toxins and capsules encoded by the pXO1 and pXO2 plasmids, respectively, are the major virulence factors. We previously reported that the pXO1 plasmid was retained in the attenuated strain of B. anthracis vaccine strains even after subculturing at high temperatures. In the present study, we reinvestigate the attenuation mechanism of Pasteur II. Sequencing of pXO1 and pXO2 from Pasteur II strain revealed mutations in these plasmids as compared to the reference sequences. Two deletions on these plasmids, one each on pXO1 and pXO2, were confirmed to be unique to the Pasteur II strain as compared to the wild-type strains. Gene replacement with homologous recombination revealed that the mutation in the promoter region of the pagR gene on pXO2, but not the mutation on pXO1, contributes to lethal levels of toxin production. This result was further confirmed by RT-PCR, western blot, and animal toxicity assays. Taken together, our results signify that the attenuation of the Pasteur II vaccine strain is caused by a mutation in the pagR gene on its pXO2 plasmid. Moreover, these data suggest that pXO2 plasmid encoded proteins are involved in the virulence of B. anthracis. PMID:27363681

  4. Improving the Anti-Toxin Abilities of the CMG2-Fc Fusion Protein with the Aid of Computational Design

    PubMed Central

    Peng, Hui; Chen, Hongxing; Chen, Huipeng; Hu, Xianwen; Yue, Junjie

    2014-01-01

    CMG2-Fc is a fusion protein composed of the extracellular domain of capillary morphogenesis protein 2 (CMG2) and the Fc region of human immunoglobulin G; CMG2-Fc neutralizes anthrax toxin and offers protection against Bacillus anthracis challenge. To enhance the efficacy of CMG2-Fc against anthrax toxin, we attempted to engineer a CMG2-Fc with an improved affinity for PA. Using the automatic design algorithm FoldX and visual inspection, we devised two CMG2-Fc variants that introduce mutations in the CMG2 binding interface and improve the computationally assessed binding affinity for PA. An experimental affinity assay revealed that the two variants showed increased binding affinity, and in vitro and in vivo toxin neutralization testing indicated that one of these mutants (CMG2-Fc(E117Q)) has superior activity against anthrax toxin and was suitable for further development as a therapeutic agent for anthrax infections. This study shows that the computational design of the PA binding interface of CMG2 to obtain CMG2-Fc variants with improving anti-toxin abilities is viable. Our results demonstrate that computational design can be further applied to generate other CMG2-Fc mutants with greatly improved therapeutic efficacy. PMID:25101992

  5. [A severe cutaneous anthrax case complicated with sepsis in Bursa, Turkey].

    PubMed

    Durmuş, Gül; Yeşilyurt, Murat; Karagöz, Alper; Demir, Canan; Eren, Nilüfer; Kılıç, Selçuk

    2013-07-01

    Anthrax is a zoonotic infection caused by Bacillus anthracis. Although the incidence of disease has been decreasing in Turkey, it is still endemic in some regions of the country. The cutaneous form of disease is the most common clinical form, usually benign and rarely causes bacteriemia and sepsis. In this report, a case of cutaneous anthrax complicated with sepsis where B.anthracis was isolated from blood and wound cultures, was presented. A 53-years-old male living in Bursa province (northwestern Turkey), admitted to the emergency ward with high fever and a lesion on the right arm. His history indicated that he is dealing with livestock breeding and injured his arm during slaughtering of a sick lamb. The infection started as a black colored painless ulcer with 2 cm in diameter on his right elbow. The case was hospitalized and penicillin G therapy was started with the preliminary diagnosis of anthrax. Bullous lesions occurred around the wound, got necrosis and integrated with the first lesion. Gram stained slides from the bullous lesions revealed capsulated gram-positive bacilli under light microscope. Gram-positive bacilli were also isolated from bullous lesions and the blood cultures. The isolates were identified and confirmed as B.anthracis by conventional and molecular methods. Antibiotic susceptibility tests were performed by E-test method and the isolates were found to be susceptible to ampicillin, tetracyclin, tigecyclin, ciprofloxacin, levofloxacin, gentamycin, chloramphenicol, erythromycin, clarithromycin, vancomycin, linezolid, daptomycin and rifampicin. The lesion became surrounded by an extensive erythema and edema and expanded to the whole arm. Moxifloxacin was initiated due to the fact that clinical progress. During the second week of the therapy, a black colored scar was observed on the wound while hyperemia and edema regressed. The necrotic tissue debridated to accelerate healing and rest of the skin defect was planned for reconstruction. The

  6. Periorbital cellulitis due to cutaneous anthrax.

    PubMed

    Gilliland, Grant; Starks, Victoria; Vrcek, Ivan; Gilliland, Connor

    2015-12-01

    Virgil's plague of the ancient world, Bacillus anthracis, is rare in developed nations. Unfortunately rural communities across the globe continue to be exposed to this potentially lethal bacterium. Herein we report a case of periorbital cutaneous anthrax infection in a 3-year-old girl from the rural area surrounding Harare, Zimbabwe with a brief review of the literature. PMID:25763844

  7. Anthrax prophylaxis: recent advances and future directions

    PubMed Central

    Williamson, E. Diane; Dyson, Edward Hugh

    2015-01-01

    Anthrax is a serious, potentially fatal disease that can present in four distinct clinical patterns depending on the route of infection (cutaneous, gastrointestinal, pneumonic, or injectional); effective strategies for prophylaxis and therapy are therefore required. This review addresses the complex mechanisms of pathogenesis employed by the bacterium and describes how, as understanding of these has developed over many years, so too have current strategies for vaccination and therapy. It covers the clinical and veterinary use of live attenuated strains of anthrax and the subsequent identification of protein sub-units for incorporation into vaccines, as well as combinations of protein sub-units with spore or other components. It also addresses the application of these vaccines for conventional prophylactic use, as well as post-exposure use in conjunction with antibiotics. It describes the licensed acellular vaccines AVA and AVP and discusses the prospects for a next generation of recombinant sub-unit vaccines for anthrax, balancing the regulatory requirement and current drive for highly defined vaccines, against the risk of losing the “danger” signals required to induce protective immunity in the vaccinee. It considers novel approaches to reduce time to immunity by means of combining, for example, dendritic cell vaccination with conventional approaches and considers current opportunities for the immunotherapy of anthrax. PMID:26441934

  8. Anthrax Vaccine: What You Need to Know

    MedlinePlus

    VACCINE INFORMATION STATEMENT Anthrax Vaccine What You Need to Know Many Vaccine Information Statements are available in Spanish and other languages. See www. immunize. org/ vis Hojas de información s obre v acunas están disponibles en e spañol y en muchos otros ...

  9. Anthrax prophylaxis: recent advances and future directions.

    PubMed

    Williamson, E Diane; Dyson, Edward Hugh

    2015-01-01

    Anthrax is a serious, potentially fatal disease that can present in four distinct clinical patterns depending on the route of infection (cutaneous, gastrointestinal, pneumonic, or injectional); effective strategies for prophylaxis and therapy are therefore required. This review addresses the complex mechanisms of pathogenesis employed by the bacterium and describes how, as understanding of these has developed over many years, so too have current strategies for vaccination and therapy. It covers the clinical and veterinary use of live attenuated strains of anthrax and the subsequent identification of protein sub-units for incorporation into vaccines, as well as combinations of protein sub-units with spore or other components. It also addresses the application of these vaccines for conventional prophylactic use, as well as post-exposure use in conjunction with antibiotics. It describes the licensed acellular vaccines AVA and AVP and discusses the prospects for a next generation of recombinant sub-unit vaccines for anthrax, balancing the regulatory requirement and current drive for highly defined vaccines, against the risk of losing the "danger" signals required to induce protective immunity in the vaccinee. It considers novel approaches to reduce time to immunity by means of combining, for example, dendritic cell vaccination with conventional approaches and considers current opportunities for the immunotherapy of anthrax. PMID:26441934

  10. Molecular pathophysiology of cerebral edema.

    PubMed

    Stokum, Jesse A; Gerzanich, Volodymyr; Simard, J Marc

    2016-03-01

    Advancements in molecular biology have led to a greater understanding of the individual proteins responsible for generating cerebral edema. In large part, the study of cerebral edema is the study of maladaptive ion transport. Following acute CNS injury, cells of the neurovascular unit, particularly brain endothelial cells and astrocytes, undergo a program of pre- and post-transcriptional changes in the activity of ion channels and transporters. These changes can result in maladaptive ion transport and the generation of abnormal osmotic forces that, ultimately, manifest as cerebral edema. This review discusses past models and current knowledge regarding the molecular and cellular pathophysiology of cerebral edema. PMID:26661240

  11. Molecular pathophysiology of cerebral edema

    PubMed Central

    Gerzanich, Volodymyr; Simard, J Marc

    2015-01-01

    Advancements in molecular biology have led to a greater understanding of the individual proteins responsible for generating cerebral edema. In large part, the study of cerebral edema is the study of maladaptive ion transport. Following acute CNS injury, cells of the neurovascular unit, particularly brain endothelial cells and astrocytes, undergo a program of pre- and post-transcriptional changes in the activity of ion channels and transporters. These changes can result in maladaptive ion transport and the generation of abnormal osmotic forces that, ultimately, manifest as cerebral edema. This review discusses past models and current knowledge regarding the molecular and cellular pathophysiology of cerebral edema. PMID:26661240

  12. Pertussis toxin

    SciTech Connect

    Sekura, R.D.; Moss, J.; Vaughan, M.

    1985-01-01

    This book contains 13 selections. Some of the titles are: Genetic and Functional Studies of Pertussis Toxin Substrates; Effect of Pertussis Toxin on the Hormonal Responsiveness of Different Tissues; Extracellular Adenylate Cyclase of Bordetella pertussis; and GTP-Regulatory Proteins are Introcellular Messagers: A Model for Hormone Action.

  13. Antibiotics Cure Anthrax in Animal Models▿

    PubMed Central

    Weiss, Shay; Kobiler, David; Levy, Haim; Pass, Avi; Ophir, Yakir; Rothschild, Nili; Tal, Arnon; Schlomovitz, Josef; Altboum, Zeev

    2011-01-01

    Respiratory anthrax, in the absence of early antibiotic treatment, is a fatal disease. This study aimed to test the efficiency of antibiotic therapy in curing infected animals and those sick with anthrax. Postexposure prophylaxis (24 h postinfection [p.i.]) of guinea pigs infected intranasally with Bacillus anthracis Vollum spores with doxycycline, ofloxacin, imipenem, and gentamicin conferred protection. However, upon termination of treatment, the animals died from respiratory anthrax. Combined treatment with antibiotics and active vaccination with a protective antigen-based vaccine leads to full protection even after cessation of treatment. Delaying the initiation of antibiotic administration to over 24 h p.i. resulted in treatment of animals with anthrax exhibiting various degrees of bacteremia and toxemia. Treatment with doxycycline or ciprofloxacin cured sick guinea pigs and rabbits exhibiting bacteremia levels up to 105 CFU/ml. Addition of anti-protective antigen (PA) antibodies augmented the efficiency of protection, allowing the cure of guinea pigs and rabbits with 10- to 20-fold-higher bacteremia levels, up to 7 × 105 CFU/ml and 2 × 106 CFU/ml, respectively. Treatment with ciprofloxacin and a monoclonal anti-PA antibody rescued rabbits with bacteremia levels up to 4 × 106 CFU/ml. During antibiotic administration, all surviving animals developed a protective immune response against development of a fatal disease and subcutaneous challenge with Vollum spores. In conclusion, these results demonstrate that antibiotic treatment can prevent the development of fatal disease in respiratory-anthrax-infected animals and can cure animals after disease establishment. A therapeutic time window of 40 h to 48 h from infection to initiation of efficient antibiotic-mediated cure was observed. PMID:21263056

  14. Enhanced Immune Response to DNA Vaccine Encoding Bacillus anthracis PA-D4 Protects Mice against Anthrax Spore Challenge

    PubMed Central

    Kim, Na Young; Chang, Dong Suk; Kim, Yeonsu; Kim, Chang Hwan; Hur, Gyeung Haeng; Yang, Jai Myung; Shin, Sungho

    2015-01-01

    Anthrax has long been considered the most probable bioweapon-induced disease. The protective antigen (PA) of Bacillus anthracis plays a crucial role in the pathogenesis of anthrax. In the current study, we evaluated the efficiency of a genetic vaccination with the fourth domain (D4) of PA, which is responsible for initial binding of the anthrax toxin to the cellular receptor. The eukaryotic expression vector was designed with the immunoglobulin M (IgM) signal sequence encoding for PA-D4, which contains codon-optimized genes. The expression and secretion of recombinant protein was confirmed in vitro in 293T cells transfected with plasmid and detected by western blotting, confocal microscopy, and enzyme-linked immunosorbent assay (ELISA). The results revealed that PA-D4 protein can be efficiently expressed and secreted at high levels into the culture medium. When plasmid DNA was given intramuscularly to mice, a significant PA-D4-specific antibody response was induced. Importantly, high titers of antibodies were maintained for nearly 1 year. Furthermore, incorporation of the SV40 enhancer in the plasmid DNA resulted in approximately a 15-fold increase in serum antibody levels in comparison with the plasmid without enhancer. The antibodies produced were predominantly the immunoglobulin G2 (IgG2) type, indicating the predominance of the Th1 response. In addition, splenocytes collected from immunized mice produced PA-D4-specific interferon gamma (IFN-γ). The biodistribution study showed that plasmid DNA was detected in most organs and it rapidly cleared from the injection site. Finally, DNA vaccination with electroporation induced a significant increase in immunogenicity and successfully protected the mice against anthrax spore challenge. Our approach to enhancing the immune response contributes to the development of DNA vaccines against anthrax and other biothreats. PMID:26430894

  15. Enhanced Immune Response to DNA Vaccine Encoding Bacillus anthracis PA-D4 Protects Mice against Anthrax Spore Challenge.

    PubMed

    Kim, Na Young; Chang, Dong Suk; Kim, Yeonsu; Kim, Chang Hwan; Hur, Gyeung Haeng; Yang, Jai Myung; Shin, Sungho

    2015-01-01

    Anthrax has long been considered the most probable bioweapon-induced disease. The protective antigen (PA) of Bacillus anthracis plays a crucial role in the pathogenesis of anthrax. In the current study, we evaluated the efficiency of a genetic vaccination with the fourth domain (D4) of PA, which is responsible for initial binding of the anthrax toxin to the cellular receptor. The eukaryotic expression vector was designed with the immunoglobulin M (IgM) signal sequence encoding for PA-D4, which contains codon-optimized genes. The expression and secretion of recombinant protein was confirmed in vitro in 293T cells transfected with plasmid and detected by western blotting, confocal microscopy, and enzyme-linked immunosorbent assay (ELISA). The results revealed that PA-D4 protein can be efficiently expressed and secreted at high levels into the culture medium. When plasmid DNA was given intramuscularly to mice, a significant PA-D4-specific antibody response was induced. Importantly, high titers of antibodies were maintained for nearly 1 year. Furthermore, incorporation of the SV40 enhancer in the plasmid DNA resulted in approximately a 15-fold increase in serum antibody levels in comparison with the plasmid without enhancer. The antibodies produced were predominantly the immunoglobulin G2 (IgG2) type, indicating the predominance of the Th1 response. In addition, splenocytes collected from immunized mice produced PA-D4-specific interferon gamma (IFN-γ). The biodistribution study showed that plasmid DNA was detected in most organs and it rapidly cleared from the injection site. Finally, DNA vaccination with electroporation induced a significant increase in immunogenicity and successfully protected the mice against anthrax spore challenge. Our approach to enhancing the immune response contributes to the development of DNA vaccines against anthrax and other biothreats. PMID:26430894

  16. A CpG-Ficoll Nanoparticle Adjuvant for Anthrax Protective Antigen Enhances Immunogenicity and Provides Single-Immunization Protection against Inhaled Anthrax in Monkeys.

    PubMed

    Kachura, Melissa A; Hickle, Colin; Kell, Sariah A; Sathe, Atul; Calacsan, Carlo; Kiwan, Radwan; Hall, Brian; Milley, Robert; Ott, Gary; Coffman, Robert L; Kanzler, Holger; Campbell, John D

    2016-01-01

    Nanoparticulate delivery systems for vaccine adjuvants, designed to enhance targeting of secondary lymphoid organs and activation of APCs, have shown substantial promise for enhanced immunopotentiation. We investigated the adjuvant activity of synthetic oligonucleotides containing CpG-rich motifs linked to the sucrose polymer Ficoll, forming soluble 50-nm particles (DV230-Ficoll), each containing >100 molecules of the TLR9 ligand, DV230. DV230-Ficoll was evaluated as an adjuvant for a candidate vaccine for anthrax using recombinant protective Ag (rPA) from Bacillus anthracis. A single immunization with rPA plus DV230-Ficoll induced 10-fold higher titers of toxin-neutralizing Abs in cynomolgus monkeys at 2 wk compared with animals immunized with equivalent amounts of monomeric DV230. Monkeys immunized either once or twice with rPA plus DV230-Ficoll were completely protected from challenge with 200 LD50 aerosolized anthrax spores. In mice, DV230-Ficoll was more potent than DV230 for the induction of innate immune responses at the injection site and draining lymph nodes. DV230-Ficoll was preferentially colocalized with rPA in key APC populations and induced greater maturation marker expression (CD69 and CD86) on these cells and stronger germinal center B and T cell responses, relative to DV230. DV230-Ficoll was also preferentially retained at the injection site and draining lymph nodes and produced fewer systemic inflammatory responses. These findings support the development of DV230-Ficoll as an adjuvant platform, particularly for vaccines such as for anthrax, for which rapid induction of protective immunity and memory with a single injection is very important. PMID:26608924

  17. Media exposure to bioterrorism: stress and the anthrax attacks.

    PubMed

    Dougall, Angela Liegey; Hayward, Michele C; Baum, Andrew

    2005-01-01

    This study examined media exposure and adjustment to anthrax bioterrorism attacks and the terrorist attacks on 9/11 in a sample of 300 people who lived distant from the attacks. Measures of direct and indirect exposure to terrorism, perceived risk of anthrax exposure, psychological distress, and outlook were assessed at 2 to 3 months and at 8 months after the first reported anthrax attack. Initial anthrax media exposure was a powerful predictor of distress, whereas subsequent anthrax media exposure only predicted negative changes in outlook over time. Perceived risk of anthrax exposure predicted distress and outlook but did not appear to mediate the effects of media exposure. Determining the nature and consequences of media exposure to threatening and frightening events like terrorism will help predict and manage response to future bioterrorism. PMID:15899708

  18. Diabetic Macular Edema

    PubMed Central

    Gundogan, Fatih C.; Yolcu, Umit; Akay, Fahrettin; Ilhan, Abdullah; Ozge, Gokhan; Uzun, Salih

    2016-01-01

    Diabetic macular edema (DME), one the most prevalent causes of visual loss in industrialized countries, may be diagnosed at any stage of diabetic retinopathy. The diagnosis, treatment, and follow up of DME have become straightforward with recent developments in fundus imaging, such as optical coherence tomography. Laser photocoagulation, intravitreal injections, and pars plana vitrectomy surgery are the current treatment modalities; however, the positive effects of currently available intravitreally injected agents are temporary. At this point, further treatment choices are needed for a permanent effect. Sources of data selection: The articles published between 1985-2015 years on major databases were searched and most appropriate 40 papers were used to write this review article. PMID:27182271

  19. Brown spider dermonecrotic toxin directly induces nephrotoxicity

    SciTech Connect

    Chaim, Olga Meiri; Sade, Youssef Bacila; Bertoni da Silveira, Rafael; Toma, Leny; Kalapothakis, Evanguedes; Chavez-Olortegui, Carlos; Mangili, Oldemir Carlos; Gremski, Waldemiro; Dietrich, Carl Peter von; Nader, Helena B.; Sanches Veiga, Silvio . E-mail: veigass@ufpr.br

    2006-02-15

    Brown spider (Loxosceles genus) venom can induce dermonecrotic lesions at the bite site and systemic manifestations including fever, vomiting, convulsions, disseminated intravascular coagulation, hemolytic anemia and acute renal failure. The venom is composed of a mixture of proteins with several molecules biochemically and biologically well characterized. The mechanism by which the venom induces renal damage is unknown. By using mice exposed to Loxosceles intermedia recombinant dermonecrotic toxin (LiRecDT), we showed direct induction of renal injuries. Microscopic analysis of renal biopsies from dermonecrotic toxin-treated mice showed histological alterations including glomerular edema and tubular necrosis. Hyalinization of tubules with deposition of proteinaceous material in the tubule lumen, tubule epithelial cell vacuoles, tubular edema and epithelial cell lysis was also observed. Leukocytic infiltration was neither observed in the glomerulus nor the tubules. Renal vessels showed no sign of inflammatory response. Additionally, biochemical analyses showed such toxin-induced changes in renal function as urine alkalinization, hematuria and azotemia with elevation of blood urea nitrogen levels. Immunofluorescence with dermonecrotic toxin antibodies and confocal microscopy analysis showed deposition and direct binding of this toxin to renal intrinsic structures. By immunoblotting with a hyperimmune dermonecrotic toxin antiserum on renal lysates from toxin-treated mice, we detected a positive signal at the region of 33-35 kDa, which strengthens the idea that renal failure is directly induced by dermonecrotic toxin. Immunofluorescence reaction with dermonecrotic toxin antibodies revealed deposition and binding of this toxin directly in MDCK epithelial cells in culture. Similarly, dermonecrotic toxin treatment caused morphological alterations of MDCK cells including cytoplasmic vacuoles, blebs, evoked impaired spreading and detached cells from each other and from

  20. Mass Spectrometric Detection of Bacterial Protein Toxins and Their Enzymatic Activity

    PubMed Central

    Kalb, Suzanne R.; Boyer, Anne E.; Barr, John R.

    2015-01-01

    Mass spectrometry has recently become a powerful technique for bacterial identification. Mass spectrometry approaches generally rely upon introduction of the bacteria into a matrix-assisted laser-desorption time-of-flight (MALDI-TOF) mass spectrometer with mass spectrometric recognition of proteins specific to that organism that form a reliable fingerprint. With some bacteria, such as Bacillus anthracis and Clostridium botulinum, the health threat posed by these organisms is not the organism itself, but rather the protein toxins produced by the organisms. One such example is botulinum neurotoxin (BoNT), a potent neurotoxin produced by C. botulinum. There are seven known serotypes of BoNT, A–G, and many of the serotypes can be further differentiated into toxin variants, which are up to 99.9% identical in some cases. Mass spectrometric proteomic techniques have been established to differentiate the serotype or toxin variant of BoNT produced by varied strains of C. botulinum. Detection of potent biological toxins requires high analytical sensitivity and mass spectrometry based methods have been developed to determine the enzymatic activity of BoNT and the anthrax lethal toxins produced by B. anthracis. This enzymatic activity, unique for each toxin, is assessed with detection of the toxin-induced cleavage of strategically designed peptide substrates by MALDI-TOF mass spectrometry offering unparalleled specificity. Furthermore, activity assays allow for the assessment of the biological activity of a toxin and its potential health risk. Such methods have become important diagnostics for botulism and anthrax. Here, we review mass spectrometry based methods for the enzymatic activity of BoNT and the anthrax lethal factor toxin. PMID:26404376

  1. Mass Spectrometric Detection of Bacterial Protein Toxins and Their Enzymatic Activity.

    PubMed

    Kalb, Suzanne R; Boyer, Anne E; Barr, John R

    2015-09-01

    Mass spectrometry has recently become a powerful technique for bacterial identification. Mass spectrometry approaches generally rely upon introduction of the bacteria into a matrix-assisted laser-desorption time-of-flight (MALDI-TOF) mass spectrometer with mass spectrometric recognition of proteins specific to that organism that form a reliable fingerprint. With some bacteria, such as Bacillus anthracis and Clostridium botulinum, the health threat posed by these organisms is not the organism itself, but rather the protein toxins produced by the organisms. One such example is botulinum neurotoxin (BoNT), a potent neurotoxin produced by C. botulinum. There are seven known serotypes of BoNT, A-G, and many of the serotypes can be further differentiated into toxin variants, which are up to 99.9% identical in some cases. Mass spectrometric proteomic techniques have been established to differentiate the serotype or toxin variant of BoNT produced by varied strains of C. botulinum. Detection of potent biological toxins requires high analytical sensitivity and mass spectrometry based methods have been developed to determine the enzymatic activity of BoNT and the anthrax lethal toxins produced by B. anthracis. This enzymatic activity, unique for each toxin, is assessed with detection of the toxin-induced cleavage of strategically designed peptide substrates by MALDI-TOF mass spectrometry offering unparalleled specificity. Furthermore, activity assays allow for the assessment of the biological activity of a toxin and its potential health risk. Such methods have become important diagnostics for botulism and anthrax. Here, we review mass spectrometry based methods for the enzymatic activity of BoNT and the anthrax lethal factor toxin. PMID:26404376

  2. Anthrax: a continuing concern in the era of bioterrorism

    PubMed Central

    2005-01-01

    Anthrax, a potentially fatal infection, is a virulent and highly contagious disease. It is caused by a gram-positive, toxigenic, spore-forming bacillus: Bacillus anthracis. For centuries, anthrax has caused disease in animals and, although uncommonly, in humans throughout the world. Descriptions of this naturally occurring disease begin in antiquity. Anthrax is primarily a disease of herbivores, which are infected by ingestion of spores from the soil. With the advent of modern microbiology, Pasteur developed the first successful anthrax vaccine in 1881. The incidence of the disease has continually decreased since the late 19th century, and animal vaccination programs drastically reduced the animal mortality from the disease. However, anthrax spores continue to be documented in soil samples from throughout the world. Research on anthrax as a biological weapon began more than 80 years ago, and today at least 17 nations are believed to have offensive biological weapons programs that include anthrax. Recent events in the USA have shown how society is affected by both hoax and real threats of anthrax bioweapons. This fourth article in the series on weapons of biowarfare/bioterrorism summarizes the historical background of anthrax as well as clinical and laboratory information useful for bioterrorism preparedness. PMID:16200179

  3. Anthrax as an example of the One Health concept.

    PubMed

    Bengis, R G; Frean, J

    2014-08-01

    Anthrax is a peracute, acute or subacute multispecies bacterial infection that occurs on many continents. It is one of the oldest infectious diseases known; the biblical fifth and sixth plagues (Exodus chapters 7 to 9) that affected first livestock and then humans were probably anthrax. From the earliest historical records until development of an effective vaccine midway through the 20th Century, anthrax was one of the foremost causes of uncontrolled mortality in cattle, sheep, goats, horses and pigs, with 'spill over' into humans, worldwide. With the development of the Sterne spore vaccine, a sharp decline in anthrax outbreaks in livestock occurred during the 1930-1980 era. There were successful national vaccination programmes in many countries during this period, complemented by the liberal use of antibiotics and the implementation of quarantine regulations and carcass disposal. However, a resurgence of this disease in livestock has been reported recently in some regions, where complacency and a false sense of security have hindered vaccination programmes. The epidemiology of anthrax involves an environmental component, as well as livestock, wildlife and human components. This makes anthrax an ideal example for discussion in the One Health context. Many outbreaks of anthrax in wildlife are undetected or unreported, owing to surveillance inadequacies and difficulties. Human disease is generally acquired accidentally during outbreaks of anthrax in domestic livestock and wildlife. The exception is deliberate targeting of humans with anthrax in the course of biowarfare or bioterrorism. PMID:25707186

  4. Human anthrax as a re-emerging disease.

    PubMed

    Doganay, Mehmet; Demiraslan, Hayati

    2015-01-01

    Anthrax is primarily a disease of herbivores and the etiological agent is B. anthracis which is a gram-positive, aerobic, spore-forming, and rod shaped bacterium. Bacillus anthracis spores are highly resistant to heat, pressure, ultraviolet and ionizing radiation, chemical agents and disinfectants. For these reasons, B. anthracis spores are an attractive choice as biological agents for the use of bioweapon and/or bioterrorism. Soil is the main reservoir for the infectious agent. The disease most commonly affects wild and domestic mammals. Human are secondarily infected by contact with infected animals and contaminated animal products or directly expose to B. anthracis spores. Anthrax occurs worldwide. This infection is still endemic or hyperendemic in both animals and humans in some part of areas of the world; particularly in Middle East, West Africa, Central Asia, some part of India, South America. However, some countries are claiming free of anthrax, and anthrax has become a re-emerging disease in western countries with the intentional outbreak. Currently, anthrax is classified according to its setting as (1) naturally occurring anthrax, (2) bioterrorism-related anthrax. Vast majority of human anthrax are occurring as naturally occurring anthrax in the world. It is also a threaten disease for western countries. The aim of this paper is to review the relevant patents, short historical perspective, microbiological and epidemiological features, clinical presentations and treatment. PMID:25851429

  5. Millipede toxin

    MedlinePlus

    ... toxin are: Hydrochloric acid Hydrogen cyanide Organic acids Phenol Cresols Benzoquinones Hydroquinones (in some millipedes) ... with plenty of soap and water. Do NOT use alcohol to wash the area. Wash eyes with ...

  6. Millipede toxin

    MedlinePlus

    ... release keeps away most predators. Some large millipede species can secrete these toxins as far as 80 ... reactions are mainly seen from contact with tropical species of millipedes. The outlook may be more serious ...

  7. Marine toxins.

    PubMed

    Whittle, K; Gallacher, S

    2000-01-01

    Seafood products are important both nutritionally and economically. Within Europe, some 12 billion Pounds of fishery products are consumed annually and an enormous variety of species are available. Although seafood is rarely implicated in food poisoning, compared to other food sources, it does provide some specific human health hazards unique to this particular resource. Generally, these are toxins from toxic microscopic algae which accumulate through the food-chain. The toxins can cause various neurological and gastrointestinal illnesses and, potentially, consumers are exposed from seafood produced within Europe, from imported products, or from seafood eaten while travelling abroad. The symptoms of illness which may be encountered, the source and mode of action of the toxins, and some emerging problems are described. European legislation aims to ensure the quality and safety of seafood products by prohibiting sale of some toxic species, setting toxin limits, requiring monitoring and controlling imports. PMID:10885118

  8. Challenges in disposing of anthrax waste.

    PubMed

    Lesperance, Ann M; Stein, Steve; Upton, Jaki F; Toomey, Chris

    2011-09-01

    Disasters often create large amounts of waste that must be managed as part of both immediate response and long-term recovery. While many federal, state, and local agencies have debris management plans, these plans often do not address chemical, biological, and radiological contamination. The Interagency Biological Restoration Demonstration's (IBRD) purpose was to holistically assess all aspects of an anthrax incident and assist in the development of a plan for long-term recovery. In the case of wide-area anthrax contamination and the follow-on response and recovery activities, a significant amount of material would require decontamination and disposal. Accordingly, IBRD facilitated the development of debris management plans to address contaminated waste through a series of interviews and workshops with local, state, and federal representatives. The outcome of these discussions was the identification of 3 primary topical areas that must be addressed: planning, unresolved research questions, and resolving regulatory issues. PMID:21882972

  9. New Insights into Gastrointestinal Anthrax Infection

    PubMed Central

    Owen, Jennifer L.; Yang, Tao; Mohamadzadeh, Mansour

    2014-01-01

    Bacterial infections are the primary cause of gastrointestinal (GI) disorders in both developing and developed countries, and are particularly dangerous for infants and children. Bacillus anthracis is the “archetype zoonotic” pathogen; no other infectious disease affects such a broad range of species, including humans. Importantly, there are more case reports of GI anthrax infection in children than inhalational disease. Early diagnosis is difficult and widespread systemic disease develops rapidly. This review highlights new findings concerning the roles of the gut epithelia, commensal microbiota, and innate lymphoid cells in initiation of disease and systemic dissemination in animal models of GI anthrax, the understanding of which is crucial to designing alternative therapies that target establishment of infection. PMID:25577136

  10. Challenges in Disposing of Anthrax Waste

    SciTech Connect

    Lesperance, Ann M.; Stein, Steven L.; Upton, Jaki F.; Toomey, Christopher

    2011-09-01

    Disasters often create large amounts of waste that must be managed as part of both immediate response and long-term recovery. While many federal, state, and local agencies have debris management plans, these plans often do not address chemical, biological, and radiological contamination. The Interagency Biological Restoration Demonstration’s (IBRD) purpose was to holistically assess all aspects of an anthrax incident and assist the development of a plan for long-term recovery. In the case of wide-area anthrax contamination and the follow-on response and recovery activities, a significant amount of material will require decontamination and disposal. Accordingly, IBRD facilitated the development of debris management plans to address contaminated waste through a series of interviews and workshops with local, state, and federal representatives. The outcome of these discussion was the identification of three primary topical areas that must be addressed: 1) Planning; 2) Unresolved research questions, and resolving regulatory issues.

  11. Macrophage-Derived Cell Lines Do Not Express Proinflammatory Cytokines after Exposure to Bacillus anthracis Lethal Toxin

    PubMed Central

    Erwin, James L.; DaSilva, Luis M.; Bavari, Sina; Little, Stephen F.; Friedlander, Arthur M.; Chanh, Tran C.

    2001-01-01

    We present evidence that Bacillus anthracis lethal toxin (LT) suppresses rather than induces proinflammatory cytokine production in macrophages. Suppression is observed with extremely low levels of LT and involves inhibition of transcription of cytokine messenger RNA. Thus, LT may contribute to anthrax pathogenesis by suppressing the inflammatory response. PMID:11160016

  12. BOTULINUM TOXIN

    PubMed Central

    Nigam, P K; Nigam, Anjana

    2010-01-01

    Botulinum toxin, one of the most poisonous biological substances known, is a neurotoxin produced by the bacterium Clostridium botulinum. C. botulinum elaborates eight antigenically distinguishable exotoxins (A, B, C1, C2, D, E, F and G). All serotypes interfere with neural transmission by blocking the release of acetylcholine, the principal neurotransmitter at the neuromuscular junction, causing muscle paralysis. The weakness induced by injection with botulinum toxin A usually lasts about three months. Botulinum toxins now play a very significant role in the management of a wide variety of medical conditions, especially strabismus and focal dystonias, hemifacial spasm, and various spastic movement disorders, headaches, hypersalivation, hyperhidrosis, and some chronic conditions that respond only partially to medical treatment. The list of possible new indications is rapidly expanding. The cosmetological applications include correction of lines, creases and wrinkling all over the face, chin, neck, and chest to dermatological applications such as hyperhidrosis. Injections with botulinum toxin are generally well tolerated and side effects are few. A precise knowledge and understanding of the functional anatomy of the mimetic muscles is absolutely necessary to correctly use botulinum toxins in clinical practice. PMID:20418969

  13. Anthrax in transit; practical experience and intellectual exchange.

    PubMed

    Jones, Susan D; Teigen, Philip M

    2008-09-01

    Focusing on three Anglo-American outbreaks of industrial anthrax, this essay engages the question of how local circumstances influenced the transmission of scientific knowledge in the late nineteenth century. Walpole (Massachusetts), Glasgow, and Bradford (Yorkshire) served as important nodes of transnational investigation into anthrax. Knowledge about the morphology and behavior of Bacillus anthracis changed little while in transit between these nodes, even during complex debates about the nature of bacterial morphology, disease causation, and spontaneous generation. Working independently of their more famous counterparts (Robert Koch and Louis Pasteur), Anglo-American anthrax investigators used visual representations of anthrax bacilli to persuade their peers that a specific, identifiable cause produced all forms of anthrax-malignant pustule (cutaneous anthrax), intestinal anthrax, and woolsorter's disease (pneumonic anthrax). By the late 1870s, this point of view also supported what we would today call an ecological notion of the disease's origins in the interactions of people, animals, and microorganisms in the context of global commerce. PMID:18959192

  14. Anthrax threat: a review of clinical and diagnostic measures.

    PubMed

    Alqurashi, Abdelrahman Mohammad

    2013-04-01

    Anthrax is the plague of the ancient world and its existence is confirmed by the Roman poet Virgil. Also it is a threat in the modern world as it can be used in biological wars and bioterrorism. Anthrax is caused by Bacillus anthracis an unmovable, aerobic, gram-positive rod. It forms spores, which can survive for years in the environment. Three clinical forms result after exposure to anthrax spores: cutaneous, respiratory, and gastro- intestinal. The cutaneous anthrax commonly prevails among humans. The respiratory form occurs most likely due to inhalation of the bacterial spores, whereas the gastrointestinal form happens after spores' ingestion. Prophylactic, early diagnosis and proper treatment will reduce mortalities of anthrax. Thus, the physicians, senior nurses and individuals at risk should be aware of the danger of this disease. PMID:23697023

  15. Bacillus cereus G9241 S-Layer Assembly Contributes to the Pathogenesis of Anthrax-Like Disease in Mice

    PubMed Central

    Wang, Ya-Ting; Oh, So-Young; Hendrickx, Antoni P. A.; Lunderberg, J. M.

    2013-01-01

    Bacillus cereus G9241, the causative agent of anthrax-like disease, harbors virulence plasmids encoding anthrax toxins as well as hyaluronic acid (HA) and B. cereus exopolysaccharide (BPS) capsules. B. cereus G9241 also harbors S-layer genes, including homologs of Bacillus anthracis surface array protein (Sap), extractable antigen 1 (EA1), and the S-layer-associated proteins (BSLs). In B. anthracis, S-layer proteins and BSLs attach via their S-layer homology domains (SLH) to the secondary cell wall polysaccharide (SCWP) in a manner requiring csaB, a predicted ketalpyruvate transferase. Here we used a genetic approach to analyze B. cereus G9241 S-layer assembly and function. Variants lacking the csaB gene synthesized SCWP but failed to retain Sap, EA1, and BSLs in the bacterial envelope. The B. cereus G9241 csaB mutant assembled capsular polysaccharides but displayed an increase in chain length relative to the wild-type strain. This phenotype is likely due to its inability to deposit BslO murein hydrolase at divisional septa. During growth under capsule-inducing conditions, B. cereus G9241 assembled BSLs (BslA and BslO) and the Sap S-layer protein, but not EA1, in the envelope. Finally, csaB-mediated assembly of S-layer proteins and BSLs in B. cereus G9241 contributes to the pathogenesis of anthrax-like disease in mice. PMID:23204457

  16. Bacillus anthracis’ lethal toxin induces broad transcriptional responses in human peripheral monocytes

    PubMed Central

    2012-01-01

    Background Anthrax lethal toxin (LT), produced by the Gram-positive bacterium Bacillus anthracis, is a highly effective zinc dependent metalloprotease that cleaves the N-terminus of mitogen-activated protein kinase kinases (MAPKK or MEKs) and is known to play a role in impairing the host immune system during an inhalation anthrax infection. Here, we present the transcriptional responses of LT treated human monocytes in order to further elucidate the mechanisms of LT inhibition on the host immune system. Results Western Blot analysis demonstrated cleavage of endogenous MEK1 and MEK3 when human monocytes were treated with 500 ng/mL LT for four hours, proving their susceptibility to anthrax lethal toxin. Furthermore, staining with annexin V and propidium iodide revealed that LT treatment did not induce human peripheral monocyte apoptosis or necrosis. Using Affymetrix Human Genome U133 Plus 2.0 Arrays, we identified over 820 probe sets differentially regulated after LT treatment at the p <0.001 significance level, interrupting the normal transduction of over 60 known pathways. As expected, the MAPKK signaling pathway was most drastically affected by LT, but numerous genes outside the well-recognized pathways were also influenced by LT including the IL-18 signaling pathway, Toll-like receptor pathway and the IFN alpha signaling pathway. Multiple genes involved in actin regulation, signal transduction, transcriptional regulation and cytokine signaling were identified after treatment with anthrax LT. Conclusion We conclude LT directly targets human peripheral monocytes and causes multiple aberrant gene responses that would be expected to be associated with defects in human monocyte’s normal signaling transduction pathways and function. This study provides further insights into the mechanisms associated with the host immune system collapse during an anthrax infection, and suggests that anthrax LT may have additional downstream targets outside the well-known MAPK

  17. Towards a human oral vaccine for anthrax: the utility of a Salmonella Typhi Ty21a-based prime-boost immunization strategy.

    PubMed

    Baillie, Leslie W J; Rodriguez, Ana L; Moore, Stephen; Atkins, Helen S; Feng, Chiguang; Nataro, James P; Pasetti, Marcela F

    2008-11-11

    We previously demonstrated the ability of an orally administered attenuated Salmonella enterica serovar Typhimurium strain expressing the protective antigen (PA) of Bacillus anthracis to confer protection against lethal anthrax aerosol spore challenge [Stokes MG, Titball RW, Neeson BN, et al. Oral administration of a Salmonella enterica-based vaccine expressing Bacillus anthracis protective antigen confers protection against aerosolized B. anthracis. Infect Immun 2007;75(April (4)):1827-34]. To extend the utility of this approach to humans we constructed variants of S. enterica serovar Typhi Ty21a, an attenuated typhoid vaccine strain licensed for human use, which expressed and exported PA via two distinct plasmid-based transport systems: the Escherichia coli HlyA haemolysin and the S. Typhi ClyA export apparatus. Murine immunogenicity studies confirmed the ability of these constructs, especially Ty21a expressing the ClyA-PA fusion protein, to stimulate strong PA-specific immune responses following intranasal immunization. These responses were further enhanced by a subsequent boost with either parenterally delivered recombinant PA or the licensed US human alum-adsorbed anthrax vaccine (AVA). Anthrax toxin neutralizing antibody responses using this prime-boost regimen were rapid, vigorous and broad in nature. The results of this study demonstrate the feasibility of employing a mucosal prime with a licensed Salmonella Typhi vaccine strain followed by a parenteral protein boost to stimulate rapid protective immunity against anthrax. PMID:18805452

  18. Dosimetric Predictors of Laryngeal Edema

    SciTech Connect

    Sanguineti, Giuseppe . E-mail: gisangui@utmb.edu; Adapala, Prashanth; Endres, Eugene J. C; Brack, Collin; Fiorino, Claudio; Sormani, Maria Pia; Parker, Brent

    2007-07-01

    Purpose: To investigate dosimetric predictors of laryngeal edema after radiotherapy (RT). Methods and Materials: A total of 66 patients were selected who had squamous cell carcinoma of the head and neck with grossly uninvolved larynx at the time of RT, no prior major surgical operation except for neck dissection and tonsillectomy, treatment planning data available for analysis, and at least one fiberoptic examination of the larynx within 2 years from RT performed by a single observer. Both the biologically equivalent mean dose at 2 Gy per fraction and the cumulative biologic dose-volume histogram of the larynx were extracted for each patient. Laryngeal edema was prospectively scored after treatment. Time to endpoint, moderate or worse laryngeal edema (Radiation Therapy Oncology Group Grade 2+), was calculated with log rank test from the date of treatment end. Results: At a median follow-up of 17.1 months (range, 0.4- 50.0 months), the risk of Grade 2+ edema was 58.9% {+-} 7%. Mean dose to the larynx, V30, V40, V50, V60, and V70 were significantly correlated with Grade 2+ edema at univariate analysis. At multivariate analysis, mean laryngeal dose (continuum, hazard ratio, 1.11; 95% confidence interval, 1.06-1.15; p < 0.001), and positive neck stage at RT (N0-x vs. N +, hazard ratio, 3.66; 95% confidence interval, 1.40-9.58; p = 0.008) were the only independent predictors. Further stratification showed that, to minimize the risk of Grade 2+ edema, the mean dose to the larynx has to be kept {<=}43.5 Gy at 2 Gy per fraction. Conclusion: Laryngeal edema is strictly correlated with various dosimetric parameters; mean dose to the larynx should be kept {<=}43.5 Gy.

  19. A case of fatal gastrointestinal anthrax in north eastern iran.

    PubMed

    Hashemi, Seyed Ahmad; Azimian, Amir; Nojumi, Sara; Garivani, Tahereh; Safamanesh, Saghar; Ghafouri, Majid

    2015-01-01

    Background. Bacillus species are aerobic or facultative anaerobic, gram-positive, or gram-variable spore-forming rods. They are ubiquitous in the environmental sources. Bacillus anthracis may usually cause three forms of anthrax: inhalation, gastrointestinal, and cutaneous. The gastrointestinal (GI) anthrax develops after eating contaminated meat. In this paper we report septic intestinal anthrax. Case Presentation. We report an isolation of Bacillus anthracis from blood culture of patient with intestinal anthrax. Bacillus anthracis was isolated from a blood culture of a 34-year-old man who had a history of severe abdominal pain, bloody diarrhea, nausea, vomiting, fever, sweating, and lethargy within 4 to 5 days after eating the meat of domestic goat. He had evidence of severe infection and septic shock and did not respond to treatments and subsequently expired 9 hours after hospitalization. Conclusion. Gastrointestinal anthrax is characterized by rapid onset, fever, and septicemia. Rapid diagnosis and prompt initiation of antibiotic therapy can help in survival. Most of previous cases of septicemic anthrax were related to injection drug users but, in our case, septicemia occurred after gastrointestinal anthrax. PMID:25918652

  20. Characterization of a multi-component anthrax vaccine designed to target the initial stages of infection as well as toxaemia

    PubMed Central

    Cote, C. K.; Kaatz, L.; Reinhardt, J.; Bozue, J.; Tobery, S. A.; Bassett, A. D.; Sanz, P.; Darnell, S. C.; Alem, F.; O’Brien, A. D.

    2012-01-01

    Current vaccine approaches to combat anthrax are effective; however, they target only a single protein [the protective antigen (PA) toxin component] that is produced after spore germination. PA production is subsequently increased during later vegetative cell proliferation. Accordingly, several aspects of the vaccine strategy could be improved. The inclusion of spore-specific antigens with PA could potentially induce protection to initial stages of the disease. Moreover, adding other epitopes to the current vaccine strategy will decrease the likelihood of encountering a strain of Bacillus anthracis (emerging or engineered) that is refractory to the vaccine. Adding recombinant spore-surface antigens (e.g. BclA, ExsFA/BxpB and p5303) to PA has been shown to augment protection afforded by the latter using a challenge model employing immunosuppressed mice challenged with spores derived from the attenuated Sterne strain of B. anthracis. This report demonstrated similar augmentation utilizing guinea pigs or mice challenged with spores of the fully virulent Ames strain or a non-toxigenic but encapsulated ΔAmes strain of B. anthracis, respectively. Additionally, it was shown that immune interference did not occur if optimal amounts of antigen were administered. By administering the toxin and spore-based immunogens simultaneously, a significant adjuvant effect was also observed in some cases. Thus, these data further support the inclusion of recombinant spore antigens in next-generation anthrax vaccine strategies. PMID:22767539

  1. Bronchial artery ligation modifies pulmonary edema after exposure to smoke with acrolein.

    PubMed

    Hales, C A; Barkin, P; Jung, W; Quinn, D; Lamborghini, D; Burke, J

    1989-09-01

    Pulmonary edema can follow smoke inhalation and is believed to be due to the multiple chemical toxins in smoke, not the heat. We have developed a synthetic smoke composed of aerosolized charcoal particles to which one toxin at a time can be added to determine whether it produces pulmonary edema. Acrolein, a common component of smoke, when added to the synthetic smoke, produced a delayed-onset pulmonary edema in dogs in which the extravascular lung water (EVLW) as detected by a double-indicator technique began to rise after 42 +/- 2 (SE) min from 148 +/- 16 to 376 +/- 60 ml at 165 min after smoke exposure. The resulting pulmonary edema was widespread macroscopically but appeared focal microscopically with fibrin deposits in alveoli adjacent to small bronchi and bronchioles. Bronchial vessels were markedly dilated and congested. Monastral blue B when injected intravenously leaked into the walls of the bronchial vessels down to the region of the small bronchioles (less than or equal to 0.5 mm ID) of acrolein-smoke-exposed dogs but not into the pulmonary vessels. Furthermore, ligation of the bronchial arteries delayed the onset of pulmonary edema (87 +/- 3 min, P less than 0.05) and lessened the magnitude (232 +/- 30 ml, P less than 0.05) at 166 +/- 3 min after acrolein-smoke exposure.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2793693

  2. [Hereditary angioneurotic edema in children].

    PubMed

    Farkas, H; Harmat, G; Füst, G; Varga, L; Visy, B

    2000-11-19

    Hereditary angioneurotic edema results from the deficiency of C1-esterase inhibitor. The clinical picture of this autosomal dominant disorder is characterized by recurrent attacks of edema formation in the subcutis and/or the submucosa. The clinical records of 21 children with established hereditary angioneurotic edema were reviewed. Follow-up care included laboratory check-ups and abdominal ultrasound. Clinical manifestations of the disease first occurred in 2.5 to 12 years of age. Mechanical trauma was the most common precipitating factor. Pedigree-analysis revealed 19 patients with afflicted relatives. Long-term prophylaxis was initiated with tranexamic acid and danazol in 10 cases; 2 children required short-term prophylaxis. Therapy improved serum complement parameters significantly and reduced the frequency and severity of clinical manifestations. Acute, life-threatening edematous attacks were treated by the administration of C1-inhibitor concentrate, which achieved the resolution of the edema within several hours. Abdominal ultrasonography performed during the attack invariably demonstrated transitory ascites that resolved spontaneously after treatment. Adequate prophylaxis and follow-up care can spare pediatric patients from edematous attacks. Undesirable adverse effects can be avoided and the patient's quality of life can be enhanced considerably by administering the lowest effective drug dose. PMID:11143287

  3. Identification of anthrax-specific signature sequence from Bacillus anthracis

    NASA Astrophysics Data System (ADS)

    Rastogi, Vipin K.; Cheng, Tu-chen

    2001-08-01

    The primary objective was to identify and clone novel chromosomal DNA fragments for use as B. anthracis-specific markers. Towards this goal, 300 random primers (RAPD technology, randomly amplified polymorphic DNA) were screened to identify polymorphic loci on the anthrax chromosome. Five such DNA fragments uniquely amplifying from anthrax chromosome were identified and isolated. These fragments were cloned in pCR vector and sequenced. Database (genebank) analysis of one of the cloned probe, VRTC899, revealed the presence of specific chromosomal DNA probe, Ba813 from anthrax. This prove also contains flanking DNA with no homology to known sequences. Availability of signature DNA probes for detection of antrax-causing agent in environmental samples is critical for field application of DNA-based sensor technologies. In conclusion, we have demonstrated application of RAPD technology for identification of anthrax-specific signature sequences. This strategy can be extended to identify signature sequences from other BW agents.

  4. Cutaneous anthrax in an unusual location: case report.

    PubMed

    Sari, Tugba; Koruk, Suda Tekin

    2015-12-01

    Cutaneous anthrax is well known, unlike anthrax of the lumbar region, which is not reported elsewhere. We present a case of anthrax of the lumbar region in a 50-year-old man. The infection was characterised by a wide, black eschar and oedema on an erythematous ground. After isolation of the Gram-positive bacilli from the skin lesions, prompt antibiotic treatment (intravenous sulbactam-ampicillin 1.5 g every six hours) was initiated. Following eradication of the bacilli after 14 days of antibiotic treatment, a split-thickness skin graft was applied. A diagnosis of anthrax depends on clinical suspicion. Early diagnosis, antibiotic and surgical treatment can facilitate the treatment and prevent development of complications. PMID:26700091

  5. Human anthrax outbreak associated with livestock exposure: Georgia, 2012.

    PubMed

    Navdarashvili, A; Doker, T J; Geleishvili, M; Haberling, D L; Kharod, G A; Rush, T H; Maes, E; Zakhashvili, K; Imnadze, P; Bower, W A; Walke, H T; Shadomy, S V

    2016-01-01

    Human anthrax cases reported in the country of Georgia increased 75% from 2011 (n = 81) to 2012 (n = 142). This increase prompted a case-control investigation using 67 culture- or PCR-confirmed cases and 134 controls matched by residence and gender to investigate risk factor(s) for infection during the month before case onset. Independent predictors most strongly associated with disease in the multivariable modelling were slaughtering animals [odds ratio (OR) 7·3, 95% confidence interval (CI) 2·9-18·1, P 1 km; 15 (12%) of 125 had sick livestock; and 11 (9%) of 128 respondents reported finding dead livestock. We recommend joint public health and veterinary anthrax case investigations to identify areas of increased risk for livestock anthrax outbreaks, annual anthrax vaccination of livestock in those areas, and public awareness education. PMID:26088361

  6. [Anthrax meningoencephalitis: a case report and review of Turkish literature].

    PubMed

    Metan, Gökhan; Uysal, Burcu; Coşkun, Ramazan; Perçin, Duygu; Doğanay, Mehmet

    2009-10-01

    The incidence of anthrax is decreasing in Turkey, however, it is still endemic in some regions of the country. Although central nervous system involvement is rare in cases with anthrax, high mortality rates are significant. Here, we report a 46-years old woman who was anthrax meningoencephalitis. The patient was from Yozgat located in Central Anatolia, Turkey. Her history revealed that following peeling the skin of sheeps and consuming their meat a week ago, a lesion developed in her left forearm and she had been treated with penicilin G with the diagnosis of cutaneous anthrax in a local health center. The patient was admitted to the emergency room of our hospital due to increased headache and loss of conciousness and diagnosed as anthrax meningitis. Crytallized penicilin G (24 MU/day IV) and vancomycin (2 g/day IV) were initiated. The macroscopy of cerebrospinal fluid (CSF) sample was haemorrhagic, white blood cell count was 40/mm3 (80% of neutrophil) and Gram staining of CSF yielded abundant gram-positive bacilli. The diagnosis was confirmed by the isolation of Bacillus anthracis from CSF culture. Although the isolate was susceptible to penicillin and dexamethasone was added to the treatment, the patient died. Review of the Turkish literature revealed seven cases of anthrax with central nervous system involvement between 1980-2008. One of the patients was an 11-years old boy and the others were adults aged between 19 and 64 years. The source of the infection was skin in four patients and inhalation in one patient. The most common findings in all of the patients were inhabitance in rural area, haemorrhagic CSF and loss of all patients despite appropriate antibiotic therapy. In conclusion, anthrax meningitis and meningoencephalitis should be considered in the differential diagnosis of haemorrhagic meningitis in areas where anthrax is endemic and high rate of mortality despite appropriate therapy should always be kept in mind. PMID:20084923

  7. [Standardization of the seeding material in producing live anthrax vaccine].

    PubMed

    Gladus, M A; Nikolaenko, Iu P; Lazareva, E S; Fatkhinurova, T I; Mashilova, G M

    1978-09-01

    Technology of obtaining dry concentrated seeding material of the anthrax bacillus STI-1 vaccine strain was worked out. The use of dry seeding material for making dry anthrax vaccine rendered the preparations obtained more standard, reduced the time required for their production, led to increase of AKM-SH productivity, and to greater profitability of the vaccine production. The vaccine preparations obtained with the use of dry seeding material did not differ from control by immunogenicity. PMID:106609

  8. Anthrax: A disease of biowarfare and public health importance

    PubMed Central

    Goel, Ajay Kumar

    2015-01-01

    Bioterrorism has received a lot of attention in the first decade of this century. Biological agents are considered attractive weapons for bioterrorism as these are easy to obtain, comparatively inexpensive to produce and exhibit widespread fear and panic than the actual potential of physical damage. Bacillus anthracis (B. anthracis), the etiologic agent of anthrax is a Gram positive, spore forming, non-motile bacterium. This is supposed to be one of the most potent BW agents because its spores are extremely resistant to natural conditions and can survive for several decades in the environment. B. anthracis spores enter the body through skin lesion (cutaneous anthrax), lungs (pulmonary anthrax), or gastrointestinal route (gastrointestinal anthrax) and germinate, giving rise to the vegetative form. Anthrax is a concern of public health also in many countries where agriculture is the main source of income including India. Anthrax has been associated with human history for a very long time and regained its popularity after Sept 2001 incidence in United States. The present review article describes the history, biology, life cycle, pathogenicity, virulence, epidemiology and potential of B. anthracis as biological weapon. PMID:25610847

  9. Naloxone-induced pulmonary edema.

    PubMed

    Schwartz, J A; Koenigsberg, M D

    1987-11-01

    We present the case of a 68-year-old woman with acute pulmonary edema secondary to the administration of naloxone to reverse an inadvertent narcotic overdose. The patient presented following a 12-hour history of increasingly bizarre behavior and confusion. A total IV dose of 1.6 mg naloxone was administered in an attempt to reverse the suspected overconsumption of a codeine-containing cough suppressant. She immediately became agitated, tachycardic, and diaphoretic; a clinical diagnosis of acute pulmonary edema was made. Following treatment with furosemide, nitroglycerin, and morphine sulfate, the patient recovered completely without further incident. Although naloxone is thought to be a safe drug with few complications, it should not be used indiscriminantly, and the smallest doses necessary to elicit the desired response should be used. PMID:3662194

  10. Hyskon-induced pulmonary edema.

    PubMed

    Mangar, D

    1993-12-01

    Hyskon (32 percent dextran-70) (Hyskon Division, Pharmacia) is used during hysteroscopy to help visualization of the uterine surfaces. Pulmonary edema of an uncertain cause has occurred in many patients. Because this study could not be conducted in humans, we determined if Hyskon caused cardiogenic or non-cardiogenic pulmonary edema in a dog model. Dogs were randomly assigned to receive an infusion of Hyskon or whole blood to sustain left ventricular end-diastolic pressure between 20 and 23 millimeters of mercury for 60 minutes. In dogs receiving blood, there was no protein in the bronchoalveolar lavage before or after blood was given. In the Hyskon group, there was no protein in the bronchoalveolar lavage before Hyskon and 0.6 +/- 1.4 milligrams per deciliter (range of 0.1 to 3.7 milligram per deciliter) after Hyskon. The ratio of bronchoalveolar lavage protein to plasma protein after Hyskon was 8.0 +/- 18.0 percent compared with zero percent in the blood group. Hyskon altered pulmonary microvascular membrane permeability, causing alveolar flooding with plasma proteins and possibly accounting for the deterioration of oxygenation and pulmonary compliance seen in patients. These results suggest a significant noncardiogenic component of Hyskon induced pulmonary edema. PMID:7505487

  11. The ecology of anthrax spores: tough but not invincible.

    PubMed Central

    Dragon, D C; Rennie, R P

    1995-01-01

    Bacillus anthracis is the causative agent of anthrax, a serious and often fatal disease of wild and domestic animals. Central to the persistence of anthrax in an area is the ability of B. anthracis to form long-lasting, highly resistant spores. Understanding the ecology of anthrax spores is essential if one hopes to control epidemics. Studies on the ecology of anthrax have found a correlation between the disease and specific soil factors, such as alkaline pH, high moisture, and high organic content. Researchers initially suggested that these factors influenced vegetative anthrax bacilli. However, subsequent research has shown that vegetative cells of B. anthracis have very specific nutrient and physiological requirements and are unlikely to survive outside a host. Review of the properties of spores of B. anthracis and other Bacillus species suggests that the specific soil factors linked to epidemic areas reflect important environmental conditions that aid the anthrax spores in causing epidemics. Specifically, high levels of calcium in the soil may help to maintain spore vitality for prolonged periods, thereby increasing the chance of spores encountering and infecting a new host. Cycles of runoff and evaporation may collect spores dispersed from previous epidemics into storage areas, thereby concentrating them. Uptake of large doses of viable spores from storage areas by susceptible animals, via altered feeding or breeding behavior, may then allow the bacterium to establish infection and cause a new epidemic. Literature search for this review was done by scanning the Life Sciences Collection 1982-1994 using the keywords "anthrax" and "calcium and spore." Images Figure 1. PMID:7773917

  12. Predictability of anthrax infection in the Serengeti, Tanzania

    PubMed Central

    Hampson, Katie; Lembo, Tiziana; Bessell, Paul; Auty, Harriet; Packer, Craig; Halliday, Jo; Beesley, Cari A.; Fyumagwa, Robert; Hoare, Richard; Ernest, Eblate; Mentzel, Christine; Metzger, Kristine L.; Mlengeya, Titus; Stamey, Karen; Roberts, Keith; Wilkins, Patricia P.; Cleaveland, Sarah

    2012-01-01

    Summary Anthrax is endemic throughout Africa, causing considerable livestock and wildlife losses and severe, sometimes fatal, infection in humans. Predicting the risk of infection is therefore important for public health, wildlife conservation and livestock economies. However, because of the intermittent and variable nature of anthrax outbreaks, associated environmental and climatic conditions, and diversity of species affected, the ecology of this multihost pathogen is poorly understood. We explored records of anthrax from the Serengeti ecosystem in north-west Tanzania where the disease has been documented in humans, domestic animals and a range of wildlife. Using spatial and temporal case-detection and seroprevalence data from wild and domestic animals, we investigated spatial, environmental, climatic and species-specific associations in exposure and disease. Anthrax was detected annually in numerous species, but large outbreaks were spatially localized, mostly affecting a few focal herbivores. Soil alkalinity and cumulative weather extremes were identified as useful spatial and temporal predictors of exposure and infection risk, and for triggering the onset of large outbreaks. Interacting ecological and behavioural factors, specifically functional groups and spatiotemporal overlap, helped to explain the variable patterns of infection and exposure among species. Synthesis and applications. Our results shed light on ecological drivers of anthrax infection and suggest that soil alkalinity and prolonged droughts or rains are useful predictors of disease occurrence that could guide risk-based surveillance. These insights should inform strategies for managing anthrax including prophylactic livestock vaccination, timing of public health warnings and antibiotic provision in high-risk areas. However, this research highlights the need for greater surveillance (environmental, serological and case-detection-orientated) to determine the mechanisms underlying anthrax dynamics

  13. 76 FR 34994 - Vaccine To Protect Children From Anthrax-Public Engagement Workshop

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-15

    ... HUMAN SERVICES Vaccine To Protect Children From Anthrax--Public Engagement Workshop AGENCY: Office of... workshop on July 7, 2011, to discuss vaccine to protect children from anthrax. This meeting is open to the... children from anthrax. The meeting will be from 9 a.m. to 4 p.m. ET. ADDRESSES: Washington Plaza Hotel,...

  14. Bacillus anthracis Capsular Conjugates Elicit Chimpanzee Polyclonal Antibodies That Protect Mice from Pulmonary Anthrax.

    PubMed

    Chen, Zhaochun; Schneerson, Rachel; Lovchik, Julie A; Dai, Zhongdong; Kubler-Kielb, Joanna; Agulto, Liane; Leppla, Stephen H; Purcell, Robert H

    2015-08-01

    The immunogenicity of Bacillus anthracis capsule (poly-γ-D-glutamic acid [PGA]) conjugated to recombinant B. anthracis protective antigen (rPA) or to tetanus toxoid (TT) was evaluated in two anthrax-naive juvenile chimpanzees. In a previous study of these conjugates, highly protective monoclonal antibodies (MAbs) against PGA were generated. This study examines the polyclonal antibody response of the same animals. Preimmune antibodies to PGA with titers of >10(3) were detected in the chimpanzees. The maximal titer of anti-PGA was induced within 1 to 2 weeks following the 1st immunization, with no booster effects following the 2nd and 3rd immunizations. Thus, the anti-PGA response in the chimpanzees resembled a secondary immune response. Screening of sera from nine unimmunized chimpanzees and six humans revealed antibodies to PGA in all samples, with an average titer of 10(3). An anti-PA response was also observed following immunization with PGA-rPA conjugate, similar to that seen following immunization with rPA alone. However, in contrast to anti-PGA, preimmune anti-PA antibody titers and those following the 1st immunization were ≤300, with the antibodies peaking above 10(4) following the 2nd immunization. The polyclonal anti-PGA shared the MAb 11D epitope and, similar to the MAbs, exerted opsonophagocytic killing of B. anthracis. Most important, the PGA-TT-induced antibodies protected mice from a lethal challenge with virulent B. anthracis spores. Our data support the use of PGA conjugates, especially PGA-rPA targeting both toxin and capsule, as expanded-spectrum anthrax vaccines. PMID:26041039

  15. Internalization and processing of Bacillus anthracis lethal toxin by toxin-sensitive and -resistant cells.

    PubMed

    Singh, Y; Leppla, S H; Bhatnagar, R; Friedlander, A M

    1989-07-01

    Anthrax lethal toxin consists of two separate proteins, protective antigen and lethal factor (LF). Certain macrophages and a mouse macrophage-like cell line, J774A.1, are lysed by low concentrations of lethal toxin. In contrast, another macrophage cell line, IC-21, and all other cell types tested were resistant to this toxin. To discover the basis for this difference, each step in the intoxication process was examined. No differences between sensitive and resistant cells were found in receptor binding or proteolytic activation of protective antigen, steps that are required prior to LF binding. To determine whether resistance results from a defect in translocation to the cytosol, we introduced LF into J774A.1 and IC-21 cells and a nonmacrophage cell line (L6 myoblast) by osmotic lysis of pinocytic vesicles. Only J774A.1 cells were lysed; no effect was observed in IC-21 and L6 cells. These results suggest that resistant cells either lack the intracellular target of LF or fail to process LF to an active form. The relatively low potency of LF introduced into J774A.1 cells by osmotic lysis suggests that protective antigen may also be required at a stage subsequent to endocytosis. PMID:2500434

  16. Membrane-Binding Mechanism of Clostridium perfringens Alpha-Toxin

    PubMed Central

    Oda, Masataka; Terao, Yutaka; Sakurai, Jun; Nagahama, Masahiro

    2015-01-01

    Clostridium perfringens alpha-toxin is a key mediator of gas gangrene, which is a life-threatening infection that manifests as fever, pain, edema, myonecrosis, and gas production. Alpha-toxin possesses phospholipase C and sphingomyelinase activities. The toxin is composed of an N-terminal domain (1–250 aa, N-domain), which is the catalytic site, and a C-terminal domain (251–370 aa, C-domain), which is the membrane-binding site. Immunization of mice with the C-domain of alpha-toxin prevents the gas gangrene caused by C. perfringens, whereas immunization with the N-domain has no effect. The central loop domain (55–93 aa), especially H….SW84Y85….G, plays an important role in the interaction with ganglioside GM1a. The toxin binds to lipid rafts in the presence of a GM1a/TrkA complex, and metabolites from phosphatidylcholine to diacylglycerol through the enzymatic activity of alpha-toxin itself. These membrane dynamics leads to the activation of endogenous PLCγ-1 via TrkA. In addition, treatment with alpha-toxin leads to the formation of diacylglycerol at membrane rafts in ganglioside-deficient DonQ cells; this in turn triggers endocytosis and cell death. This article summarizes the current the membrane-binding mechanism of alpha-toxin in detail. PMID:26633512

  17. [MODELING INFLAMMATORY EDEMA: ARE THE MODELS INTERCHANGEABLE].

    PubMed

    Hanh, Cong Hong; Khaziakhmetova, V N; Ziganshina, L E

    2015-01-01

    Experimental modeling of inflammatory edema by sub-plantar injection of carrageenan and formalin in mice and rats is widely used to evaluate potential anti-inflammatory activity of new drugs. This systematic analysis of published data showed that carrageenan induced paw edema model is used for evaluating the anti-inflammatory activity mostly in rats rather than mice. Formalin induced paw edema in rats and mice is used primarily for evaluation of the analgesic activity of drugs. Taken together, the results of this systematic review of available literature on edema modeling substantiate recommendation to use carrageenan paw edema in rats and formalin paw edema in mice as complementary, but not interchangeable models of inflammation. PMID:26591204

  18. Wanted, an Anthrax vaccine: Dead or Alive?

    PubMed Central

    Smith, Kendall A

    2005-01-01

    It has been more than 100 years since the realization that microbes are capable of causing disease. In that time, we have learned a great deal as to how each organism has adapted to the immune system so as to avoid elimination. As well, we have also learned an immense amount since Louis Pasteur first proposed that the solution to infectious diseases was to culture the microbes and attenuate their virulence, so as to use them as vaccines. From the optimism and promise of the 19th century and immunization as the ultimate answer to the invasion by the microbial world, to the scientific realities of the 21st century, it is of interest to retrace the steps of the earliest microbiologists cum immunologists, to realize how far we've come, as well as how far we yet have to go. This editorial focuses on the history of anthrax as a microbial disease, and the earliest efforts at producing a vaccine for its prevention. PMID:15836780

  19. Sverdlovsk Anthrax Outbreak: An Educational Case Study

    NASA Astrophysics Data System (ADS)

    Steele, S. J.; van der Vink, G.

    2002-05-01

    In April and May of 1979 an Anthrax epidemic broke out in the city of Sverdlovsk (now Ekaterinburg) in the former Soviet Union. Sixty-four people were reported to have died from the outbreak, although there is still debate concerning the actual number of victims. While Soviet officials initially attributed this outbreak to contaminated meat, the US Government maintained that the outbreak was due to a leakage from a biological weapons facility. We have created and implemented an undergraduate educational exercise based on the forensic analysis of this event. Students were provided case data of the victims, area satellite images and meteorological data. One goal of the exercise was for students to reconstruct the most probable scenario of events through valid inference based on the limited information and uncertainties associated with the data set. Another goal was to make students sensitive to issues of biological weapons and bioterrorism. The exercise was highly rated by students even before the events of September 11. There is a clear need to educate students, particularly in the sciences, to be aware of the signatures of terrorist activities. Evidence of terrorist activities is more likely to appear from unintended discoveries than from active intelligence gathering. We believe our national security can be enhanced by sensitizing those that monitor the natural environment to the signatures of terrorist activities through the types of educational exercises that we have developed.

  20. Epidemiologic response to anthrax outbreaks: field investigations, 1950-2001.

    PubMed

    Bales, Michael E; Dannenberg, Andrew L; Brachman, Philip S; Kaufmann, Arnold F; Klatsky, Peter C; Ashford, David A

    2002-10-01

    We used unpublished reports, published manuscripts, and communication with investigators to identify and summarize 49 anthrax-related epidemiologic field investigations conducted by the Centers for Disease Control and Prevention from 1950 to August 2001. Of 41 investigations in which Bacillus anthracis caused human or animal disease, 24 were in agricultural settings, 11 in textile mills, and 6 in other settings. Among the other investigations, two focused on building decontamination, one was a response to bioterrorism threats, and five involved other causes. Knowledge gained in these investigations helped guide the public health response to the October 2001 intentional release of B. anthracis, especially by addressing the management of anthrax threats, prevention of occupational anthrax, use of antibiotic prophylaxis in exposed persons, use of vaccination, spread of B. anthracis spores in aerosols, clinical diagnostic and laboratory confirmation methods, techniques for environmental sampling of exposed surfaces, and methods for decontaminating buildings. PMID:12396934

  1. Antimicrobial Postexposure Prophylaxis for Anthrax: Adverse Events and Adherence

    PubMed Central

    Soriano-Gabarro, Montse; Zell, Elizabeth R.; Hayslett, James; Lukacs, Susan; Goldstein, Susan; Factor, Stephanie; Jones, Joshua; Ridzon, Renee; Williams, Ian; Rosenstein, Nancy

    2002-01-01

    We collected data during postexposure antimicrobial prophylaxis campaigns and from a prophylaxis program evaluation 60 days after start of antimicrobial prophylaxis involving persons from six U.S. sites where Bacillus anthracis exposures occurred. Adverse events associated with antimicrobial prophylaxis to prevent anthrax were commonly reported, but hospitalizations and serious adverse events as defined by Food and Drug Administration criteria were rare. Overall adherence during 60 days of antimicrobial prophylaxis was poor (44%), ranging from 21% of persons exposed in the Morgan postal facility in New York City to 64% of persons exposed at the Brentwood postal facility in Washington, D.C. Adherence was highest among participants in an investigational new drug protocol to receive additional antibiotics with or without anthrax vaccine—a likely surrogate for anthrax risk perception. Adherence of <60 days was not consistently associated with adverse events. PMID:12396927

  2. Simulation modeling of anthrax spore dispersion in a bioterrorism incident.

    PubMed

    Reshetin, Vladimir P; Regens, James L

    2003-12-01

    Recent events have increased awareness of the risk posed by terrorist attacks. Bacillus anthracis has resurfaced in the 21st century as a deadly agent of bioterrorism because of its potential for causing massive civilian casualties. This analysis presents the results of a computer simulation of the dispersion of anthrax spores in a typical 50-story, high-rise building after an intentional release during a bioterrorist incident. The model simulates aerosol dispersion in the case of intensive, small-scale convection, which equalizes the concentration of anthrax spores over the building volume. The model can be used to predict the time interval required for spore dispersion throughout a building after a terrorist attack in a high-rise building. The analysis reveals that an aerosol release of even a relatively small volume of anthrax spores during a terrorist incident has the potential to quickly distribute concentrations that are infectious throughout the building. PMID:14641889

  3. An anthrax subunit vaccine candidate based on protective regions of Bacillus anthracis protective antigen and lethal factor.

    PubMed

    Baillie, Les W; Huwar, Theresa B; Moore, Stephen; Mellado-Sanchez, Gabriela; Rodriguez, Liliana; Neeson, Brendan N; Flick-Smith, Helen C; Jenner, Dominic C; Atkins, Helen S; Ingram, Rebecca J; Altmann, Danny M; Nataro, James P; Pasetti, Marcela F

    2010-09-24

    Studies have confirmed the key role of Bacillus anthracis protective antigen (PA) in the US and UK human anthrax vaccines. However, given the tripartite nature of the toxin, other components, including lethal factor (LF), are also likely to contribute to protection. We examined the antibody and T cell responses to PA and LF in human volunteers immunized with the UK anthrax vaccine (AVP). Individual LF domains were assessed for immunogenicity in mice when given alone or with PA. Based on the results obtained, a novel fusion protein comprising D1 of LF and the host cell-binding domain of PA (D4) was assessed for protective efficacy. Murine protection studies demonstrated that both full-length LF and D1 of LF conferred complete protection against a lethal intraperitoneal challenge with B. anthracis STI spores. Subsequent studies with the LFD1-PAD4 fusion protein showed a similar level of protection. LF is immunogenic in humans and is likely to contribute to the protection stimulated by AVP. A single vaccine comprising protective regions from LF and PA would simplify production and confer a broader spectrum of protection than that seen with PA alone. PMID:20691267

  4. Reexpansion pulmonary edema in children

    PubMed Central

    Rodrigues, Antonio Lucas L.; Lopes, Carlos Eduardo; Romaneli, Mariana Tresoldi das N.; Fraga, Andrea de Melo A.; Pereira, Ricardo Mendes; Tresoldi, Antonia Teresinha

    2013-01-01

    OBJECTIVE To present a case of a patient with clinical and radiological features of reexpansion pulmonary edema, a rare and potentially fatal disease. CASE DESCRIPTION An 11-year-old boy presenting fever, clinical signs and radiological features of large pleural effusion initially treated as a parapneumonic process. Due to clinical deterioration he underwent tube thoracostomy, with evacuation of 3,000 mL of fluid; he shortly presented acute respiratory insufficiency and needed mechanical ventilation. He had an atypical evolution (extubated twice with no satisfactory response). Computerized tomography findings matched those of reexpansion edema. He recovered satisfactorily after intensive care, and pleural tuberculosis was diagnosed afterwards. COMMENTS Despite its rareness in the pediatric population (only five case reports gathered), the knowledge of this pathology and its prevention is very important, due to high mortality rates. It is recommended, among other measures, slow evacuation of the pleural effusion, not removing more than 1,500 mL of fluid at once. PMID:24142327

  5. Progress in Drug Treatment of Cerebral Edema.

    PubMed

    Deng, Y Y; Shen, F C; Xie, D; Han, Q P; Fang, M; Chen, C B; Zeng, H K

    2016-01-01

    Cerebral edema causes intracranial hypertension (ICH) which leads to severe outcome of patients in the clinical setting. Effective anti-edema therapy may significantly decrease the mortality in a variety of neurological conditions. At present drug treatment is a cornerstone in the management of cerebral edema. Osmotherapy has been the mainstay of pharmacologic therapy. Mannitol and hypertonic saline (HS) are the most commonly used osmotic agents. The relative safety and efficacy of HS and mannitol in the treatment of cerebral edema and reduction of enhanced ICP have been demonstrated in the past decades. Apart from its osmotic force, HS exerts anti-edema effects partly through inhibition of Na(+)-K(+)-2Cl(-) Cotransporter-1 (NKCC1) and aquaporin 4 (AQP4) expression in astrocytes. Melatonin may also reduce brain edema and exert neuroprotective effect on several central nervous system diseases through inhibition of inflammatory response. The inhibitors of Na/H exchanger, NKCC and AQP4 may attenuate brain edema formation through inhibition of excessive transportation of ion and water from blood into the cerebral tissue. In this review we survey some of the most recent findings in the drug treatment of brain edema focusing on the use of osmotherapy, melatonin and inhibitors of ion cotransporters and water channels. A better understanding of the molecular mechanism of these agents would help to improve in the clinical management of patients with brain edema. PMID:26948324

  6. Edema and Tetraparesis in a Miniature Pig after Allogeneic Hematopoietic Cell Transplantation

    PubMed Central

    Crepeau, Rebecca; Matar, Abraham; Spitzer, Thomas R; Robson, Simon; Pathiraja, Vimukthi; Sachs, David H; Huang, Christene A; Duran-Struuck, Raimon

    2012-01-01

    A 3-mo-old, 12-kg, intact, miniature pig presented with severe neurologic signs on day 8 after hematopoietic cell transplantation. This pig had received an immunosuppressive regimen before transplantation that included an antiCD3 immunotoxin for T-cell depletion, 100 cGy of total-body irradiation, and cyclosporine for 45 d. The pig began exhibiting erythematous lesions on posttransplantation day 7. He also demonstrated increased conscious proprioceptive deficits and recumbency but normal mentation. Neurologic signs worsened over several days; the pig became lethargic but remained afebrile. Conjunctival swelling developed on posttransplantation day 9, which subsequently spread to the animal's head, ears and hocks by day 10. Analgesics were given for pain, and cyclosporine levels were decreased. Despite the measures taken, neurologic signs progressed. Given the worsening subcutaneous edema and neurologic status, Escherichia coli infection was suspected, and treatment with a third-generation cephalosporin was instituted. The clinical signs resolved within 12 h after the start of antibiotics. ‘Shiga-like’ toxin from E. coli can cause peracute toxemia and induce ataxia, paralysis, and recumbency. Other common and pathognomonic findings include periocular edema and variable edema in other subcutaneous regions. A fecal sample demonstrated an overgrowth of gram-negative, lactose-fermenting colonies. On the basis of the clinical presentation, exclusion of other potential conditions compatible with edema and neurologic diseases, physical exam findings, microbiology and the resolution of signs after therapy, the pig was diagnosed with edema disease. PMID:23043783

  7. Coordinated response to reports of possible anthrax contamination, Idaho, 2001.

    PubMed

    Tengelsen, Leslie; Hudson, Richard; Barnes, Shana; Hahn, Christine

    2002-10-01

    In 2001, the intentional release of anthrax spores in the eastern United States increased concern about exposure to anthrax nationwide, and residents of Idaho sought assistance. Response from state and local agencies was required, increasing the strain on epidemiologists, laboratorians, and communications personnel. In late 2001, Idaho's public health communications system handled 133 calls about suspicious powders. For each call, a multiagency bridge call was established, and participants (public health officials, epidemiologists, police, Federal Bureau of Investigation personnel, hazardous materials officials, and others) determined which samples would be tested by the state public health laboratory. A triage system for calls helped relieve the burden on public safety and health systems. PMID:12396922

  8. Agar-Gel Precipitin Technique in Anthrax Antibody Determinations1

    PubMed Central

    Ray, John G.; Kadull, Paul J.

    1964-01-01

    A modification of the agar-gel precipitation inhibition technique of Thorne and Belton for detecting anthrax antibodies reduces inconsistency of visually determined end points on the same sera observed by different technicians. Determination of the minimal reacting concentrations of the anthrax antigen and antibody reagents, modifications of the visualization apparatus, methods for combining reagents, and length of incubation periods contribute to the ease of the end-point determinations and the uniformity of results. When compared with the previous technique, the modified procedure is less time-consuming while retaining satisfactory reproducibility, simplicity, specificity, and sensitivity. Images FIG. 1 FIG. 2 PMID:14201088

  9. Micromotors to capture and destroy anthrax simulant spores.

    PubMed

    Orozco, Jahir; Pan, Guoqing; Sattayasamitsathit, Sirilak; Galarnyk, Michael; Wang, Joseph

    2015-03-01

    Towards addressing the need for detecting and eliminating biothreats, we describe a micromotor-based approach for screening, capturing, isolating and destroying anthrax simulant spores in a simple and rapid manner with minimal sample processing. The B. globilli antibody-functionalized micromotors can recognize, capture and transport B. globigii spores in environmental matrices, while showing non-interactions with excess of non-target bacteria. Efficient destruction of the anthrax simulant spores is demonstrated via the micromotor-induced mixing of a mild oxidizing solution. The new micromotor-based approach paves a way to dynamic multifunctional systems that rapidly recognize, isolate, capture and destroy biological threats. PMID:25622851

  10. Potent inhibitors of anthrax lethal factor from green tea

    PubMed Central

    Dell'Aica, Isabella; Donà, Massimo; Tonello, Fiorella; Piris, Alejandro; Mock, Michèle; Montecucco, Cesare; Garbisa, Spiridione

    2004-01-01

    The anthrax lethal factor (LF) has a major role in the development of anthrax. LF is delivered by the protective antigen (PA) inside the cell, where it exerts its metalloprotease activity on the N-terminus of MAPK-kinases. PA+LF are cytotoxic to macrophages in culture and kill the Fischer 344 rat when injected intravenously. We describe here the properties of some polyphenols contained in green tea as powerful inhibitors of LF metalloproteolytic activity, and how the main catechin of green tea, (−)epigallocatechin-3-gallate, prevents the LF-induced death of macrophages and Fischer 344 rats. PMID:15031715

  11. Cationic PAMAM Dendrimers as Pore-Blocking Binary Toxin Inhibitors

    PubMed Central

    2015-01-01

    Dendrimers are unique highly branched macromolecules with numerous groundbreaking biomedical applications under development. Here we identified poly(amido amine) (PAMAM) dendrimers as novel blockers for the pore-forming B components of the binary anthrax toxin (PA63) and Clostridium botulinum C2 toxin (C2IIa). These pores are essential for delivery of the enzymatic A components of the internalized toxins from endosomes into the cytosol of target cells. We demonstrate that at low μM concentrations cationic PAMAM dendrimers block PA63 and C2IIa to inhibit channel-mediated transport of the A components, thereby protecting HeLa and Vero cells from intoxication. By channel reconstitution and high-resolution current recording, we show that the PAMAM dendrimers obstruct transmembrane PA63 and C2IIa pores in planar lipid bilayers at nM concentrations. These findings suggest a new potential role for the PAMAM dendrimers as effective polyvalent channel-blocking inhibitors, which can protect human target cells from intoxication with binary toxins from pathogenic bacteria. PMID:24954629

  12. Recombinant Protective Antigen Anthrax Vaccine Improves Survival when Administered as a Postexposure Prophylaxis Countermeasure with Antibiotic in the New Zealand White Rabbit Model of Inhalation Anthrax

    PubMed Central

    Bourdage, James S.; Williamson, E. Diane; Duchars, Matthew; Fuerst, Thomas R.; Fusco, Peter C.

    2012-01-01

    Inhalation anthrax is a potentially lethal form of disease resulting from exposure to aerosolized Bacillus anthracis spores. Over the last decade, incidents spanning from the deliberate mailing of B. anthracis spores to incidental exposures in users of illegal drugs have highlighted the importance of developing new medical countermeasures to protect people who have been exposed to “anthrax spores” and are at risk of developing disease. The New Zealand White rabbit (NZWR) is a well-characterized model that has a pathogenesis and clinical presentation similar to those seen in humans. This article reports how the NZWR model was adapted to evaluate postexposure prophylaxis using a recombinant protective antigen (rPA) vaccine in combination with an oral antibiotic, levofloxacin. NZWRs were exposed to multiples of the 50% lethal dose (LD50) of B. anthracis spores and then vaccinated immediately (day 0) and again on day 7 postexposure. Levofloxacin was administered daily beginning at 6 to 12 h postexposure for 7 treatments. Rabbits were evaluated for clinical signs of disease, fever, bacteremia, immune response, and survival. A robust immune response (IgG anti-rPA and toxin-neutralizing antibodies) was observed in all vaccinated groups on days 10 to 12. Levofloxacin plus either 30 or 100 μg rPA vaccine resulted in a 100% survival rate (18 of 18 per group), and a vaccine dose as low as 10 μg rPA resulted in an 89% survival rate (16 of 18) when used in combination with levofloxacin. In NZWRs that received antibiotic alone, the survival rate was 56% (10 of 18). There was no adverse effect on the development of a specific IgG response to rPA in unchallenged NZWRs that received the combination treatment of vaccine plus antibiotic. This study demonstrated that an accelerated two-dose regimen of rPA vaccine coadministered on days 0 and 7 with 7 days of levofloxacin therapy results in a significantly greater survival rate than with antibiotic treatment alone. Combination of

  13. *CYANOBACTERIA AND THEIR TOXINS

    EPA Science Inventory

    Cyanobacteria, or blue-green algae, are naturally-occurring contaminants of surface waters worldwide. These photosynthesizing prokaryotes thrive in warm, shallow, nutrient-rich waters. Many produce potent toxins as secondary metabolites. Cyanobacteria toxins have been document...

  14. Botulinum toxin injection - larynx

    MedlinePlus

    Injection laryngoplasty; Botox-larynx: spasmodic dysphonia-BTX; Essential voice tremor (EVT)-btx; Glottic insufficiency; Percutaneous electromyography-guided botulinum toxin treatment; Percutaneous indirect laryngoscopy-guided botulinum toxin Treatment; ...

  15. Stool C. difficile toxin

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003590.htm Stool C. difficile toxin To use the sharing features on this page, please enable JavaScript. The stool C. difficile toxin test detects harmful substances produced by ...

  16. Botox (Botulinum Toxin)

    MedlinePlus

    ... people when there are many effective and safe cosmetic procedures that can temporarily reduce a very prominent ... form of botulinum toxin is Type A (Botox® Cosmetic, Allergan, Inc). Botulinum toxin, what we will now ...

  17. Transient Co-Expression of Post-Transcriptional Gene Silencing Suppressors for Increased in Planta Expression of a Recombinant Anthrax Receptor Fusion Protein

    PubMed Central

    Arzola, Lucas; Chen, Junxing; Rattanaporn, Kittipong; Maclean, James M.; McDonald, Karen A.

    2011-01-01

    Potential epidemics of infectious diseases and the constant threat of bioterrorism demand rapid, scalable, and cost-efficient manufacturing of therapeutic proteins. Molecular farming of tobacco plants provides an alternative for the recombinant production of therapeutics. We have developed a transient production platform that uses Agrobacterium infiltration of Nicotiana benthamiana plants to express a novel anthrax receptor decoy protein (immunoadhesin), CMG2-Fc. This chimeric fusion protein, designed to protect against the deadly anthrax toxins, is composed of the von Willebrand factor A (VWA) domain of human capillary morphogenesis 2 (CMG2), an effective anthrax toxin receptor, and the Fc region of human immunoglobulin G (IgG). We evaluated, in N. benthamiana intact plants and detached leaves, the expression of CMG2-Fc under the control of the constitutive CaMV 35S promoter, and the co-expression of CMG2-Fc with nine different viral suppressors of post-transcriptional gene silencing (PTGS): p1, p10, p19, p21, p24, p25, p38, 2b, and HCPro. Overall, transient CMG2-Fc expression was higher on intact plants than detached leaves. Maximum expression was observed with p1 co-expression at 3.5 days post-infiltration (DPI), with a level of 0.56 g CMG2-Fc per kg of leaf fresh weight and 1.5% of the total soluble protein, a ten-fold increase in expression when compared to absence of suppression. Co-expression with the p25 PTGS suppressor also significantly increased the CMG2-Fc expression level after just 3.5 DPI. PMID:21954339

  18. Reinke Edema: Watch For Vocal Fold Cysts.

    PubMed

    Tüzüner, Arzu; Demirci, Sule; Yavanoglu, Ahmet; Kurkcuoglu, Melih; Arslan, Necmi

    2015-06-01

    Reinke edema is one of the common cause of dysphonia middle-aged population, and severe thickening of vocal folds require surgical treatment. Smoking plays a major role on etiology. Vocal fold cysts are also benign lesions and vocal trauma blamed for acquired cysts. We would like to present 3 cases with vocal fold cyst related with Reinke edema. First case had a subepidermal epidermoid cyst with Reinke edema, which could be easily observed before surgery during laryngostroboscopy. Second case had a mucous retention cyst into the edematous Reinke tissue, which was detected during surgical intervention, and third case had a epidermoid cyst that occurred 2 months after before microlaryngeal operation regarding Reinke edema reduction. These 3 cases revealed that surgical management of Reinke edema needs a careful dissection and close follow-up after surgery for presence of vocal fold cysts. PMID:26080256

  19. Portable Anthrax Testing with Lab-in-a-Pocket

    SciTech Connect

    Finley, Melissa; Koskelo, Markku; Edwards, Thayne; Kadner, Steve; Beckes-Talcot, Judy; Harper, Jason; Shawwa, Luay

    2014-10-24

    BaDx (Bacillus anthracis Diagnostics) is a lab-in-a-pocket device to sample, sense, and diagnose bacteria that cause anthrax. It accomplishes these tasks in environments with no power, refrigerated storage, or laboratory equipment. BaDx was designed to be used with minimal or no training, and to keep handlers safe.

  20. Growth medium for the rapid isolation and identification of anthrax

    NASA Astrophysics Data System (ADS)

    Kiel, Johnathan L.; Parker, Jill E.; Grubbs, Teri R.; Alls, John L.

    2000-07-01

    Anthrax has been recognized as a highly likely biological warfare or terrorist agent. The purpose of this work was to design a culture technique to rapidly isolate and identify `live' anthrax. In liquid or solid media form, 3AT medium (3-amino-L-tyrosine, the main ingredient) accelerated germination and growth of anthrax spores in 5 to 6 hours to a point expected at 18 to 24 hours with ordinary medium. During accelerated growth, standard definitive diagnostic tests such as sensitivity to lysis by penicillin or bacteriophage can be run. During this time, the bacteria synthesized a fluorescent and thermochemiluminescent polymer. Bacteria captured by specific antibody are, therefore, already labeled. Because living bacteria are required to generate the polymer, the test converts immunoassays for anthrax into viability assays. Furthermore, the polymer formation leads to the death of the vegetative form and non-viability of the spores produced in the medium. By altering the formulation of the medium, other microbes and even animal and human cells can be grown in it and labeled (including viruses grown in the animal or human cells).

  1. Space Technology to Device that Destroys Pathogens Such As Anthrax

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This is a photo of a technician at KES Science and Technology Inc., in Kernesaw, Georgia, assembling the AiroCide Ti02, an anthrax-killing device about the size of a small coffee table. The anthrax-killing air scrubber, AiroCide Ti02, is a tabletop-size metal box that bolts to office ceilings or walls. Its fans draw in airborne spores and airflow forces them through a maze of tubes. Inside, hydroxyl radicals (OH-) attack and kill pathogens. Most remaining spores are destroyed by high-energy ultraviolet photons. Building miniature greenhouses for experiments on the International Space Station has led to the invention of this device that annihilates anthrax, a bacteria that can be deadly when inhaled. The research enabling the invention started at the University of Wisconsin's (Madison) Center for Space Automation and Robotics (WCSAR), one of 17 NASA Commercial Space Centers. A special coating technology used in this anthrax-killing invention is also being used inside WCSAR-built plant growth units on the International Space Station. This commercial research is managed by the Space Product Development Program at the Marshall Space Flight Center.

  2. 9 CFR 113.66 - Anthrax Spore Vaccine-Nonencapsulated.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... in 9 CFR 113.64 and the requirements in this paragraph. Any serial or subserial found unsatisfactory... serial or first subserial shall be tested for safety in sheep or goats by the methods described in 9 CFR... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Anthrax Spore...

  3. 9 CFR 113.66 - Anthrax Spore Vaccine-Nonencapsulated.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... in 9 CFR 113.64 and the requirements in this paragraph. Any serial or subserial found unsatisfactory... serial or first subserial shall be tested for safety in sheep or goats by the methods described in 9 CFR... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Anthrax Spore...

  4. 9 CFR 113.66 - Anthrax Spore Vaccine-Nonencapsulated.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... in 9 CFR 113.64 and the requirements in this paragraph. Any serial or subserial found unsatisfactory... serial or first subserial shall be tested for safety in sheep or goats by the methods described in 9 CFR... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Anthrax Spore...

  5. 9 CFR 113.66 - Anthrax Spore Vaccine-Nonencapsulated.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... in 9 CFR 113.64 and the requirements in this paragraph. Any serial or subserial found unsatisfactory... serial or first subserial shall be tested for safety in sheep or goats by the methods described in 9 CFR... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Anthrax Spore...

  6. 9 CFR 113.66 - Anthrax Spore Vaccine-Nonencapsulated.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... in 9 CFR 113.64 and the requirements in this paragraph. Any serial or subserial found unsatisfactory... serial or first subserial shall be tested for safety in sheep or goats by the methods described in 9 CFR... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Anthrax Spore...

  7. Detection of Protein Toxins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have focused on ricin, shiga-like toxin, botulinum neurotoxin (BoNT), and staphylococcal enterotoxin A (SEA), developing sensitive test methods for toxins and marker compounds in food matrices. Although animal models provide the best means for risk assessment, especially for crude toxins in compl...

  8. Centers for Disease Control and Prevention Expert Panel Meetings on Prevention and Treatment of Anthrax in Adults

    PubMed Central

    Hendricks, Katherine A.; Wright, Mary E.; Shadomy, Sean V.; Bradley, John S.; Morrow, Meredith G.; Pavia, Andy T.; Rubinstein, Ethan; Holty, Jon-Erik C.; Messonnier, Nancy E.; Smith, Theresa L.; Pesik, Nicki; Treadwell, Tracee A.

    2014-01-01

    The Centers for Disease Control and Prevention convened panels of anthrax experts to review and update guidelines for anthrax postexposure prophylaxis and treatment. The panels included civilian and military anthrax experts and clinicians with experience treating anthrax patients. Specialties represented included internal medicine, pediatrics, obstetrics, infectious disease, emergency medicine, critical care, pulmonology, hematology, and nephrology. Panelists discussed recent patients with systemic anthrax; reviews of published, unpublished, and proprietary data regarding antimicrobial drugs and anthrax antitoxins; and critical care measures of potential benefit to patients with anthrax. This article updates antimicrobial postexposure prophylaxis and antimicrobial and antitoxin treatment options and describes potentially beneficial critical care measures for persons with anthrax, including clinical procedures for infected nonpregnant adults. Changes from previous guidelines include an expanded discussion of critical care and clinical procedures and additional antimicrobial choices, including preferred antimicrobial drug treatment for possible anthrax meningitis. PMID:24447897

  9. First Autochthonous Coinfected Anthrax in an Immunocompetent Patient.

    PubMed

    Afshar, Parvaneh; Hedayati, Mohammad Taghi; Aslani, Narges; Khodavaisy, Sadegh; Babamahmoodi, Farhang; Mahdavi, Mohammad Reza; Dolatabadi, Somayeh; Badali, Hamid

    2015-01-01

    Cutaneous anthrax has a mortality rate of 20% if no antibacterial treatment is applied. The clinical manifestations of cutaneous anthrax are obviously striking, but coinfection may produce atypical lesions and mask the clinical manifestations and proper laboratory diagnosis. Anthrax is known to be more common in the Middle East and Iran is one of the countries in which the zoonotic form of anthrax may still be encountered. We report a case of a 19-years-old male who used to apply Venetian ceruse on his skin. Venetian ceruse (also known as Spirits of Saturn) is an old cosmetic product used for skin whitening traditionally made from sheep's spinal cord. The patient referred to the Referral Laboratory, Mazandaran University of Medical Sciences, Sari, Iran, with atypical dermatosis, pronounced pain, and oedema of the affected tissue. It was confirmed by both conventional and molecular analysis that culture was a mixture of Bacillus anthracis and Trichophyton interdigitale. The patient was initially treated with ceftriaxone (1000 mg/day for two weeks), gentamicin (1.5-2 mg/kg/day), terbinafine (200 mg/week for one month), and 1% clotrimazole cream (5 weeks) two times per day which resulted in gradual improvement. No relapse could be detected after one-year follow-up. Anthrax infection might present a broader spectrum of symptoms than expected by clinicians. These unfamiliar characteristics may lead to delayed diagnosis, inadequate treatment, and higher mortality rate. Clinicians need to be aware of this issue in order to have successful management over this infection. PMID:26451148

  10. First Autochthonous Coinfected Anthrax in an Immunocompetent Patient

    PubMed Central

    Afshar, Parvaneh; Hedayati, Mohammad Taghi; Aslani, Narges; Khodavaisy, Sadegh; Babamahmoodi, Farhang; Mahdavi, Mohammad Reza; Dolatabadi, Somayeh; Badali, Hamid

    2015-01-01

    Cutaneous anthrax has a mortality rate of 20% if no antibacterial treatment is applied. The clinical manifestations of cutaneous anthrax are obviously striking, but coinfection may produce atypical lesions and mask the clinical manifestations and proper laboratory diagnosis. Anthrax is known to be more common in the Middle East and Iran is one of the countries in which the zoonotic form of anthrax may still be encountered. We report a case of a 19-years-old male who used to apply Venetian ceruse on his skin. Venetian ceruse (also known as Spirits of Saturn) is an old cosmetic product used for skin whitening traditionally made from sheep's spinal cord. The patient referred to the Referral Laboratory, Mazandaran University of Medical Sciences, Sari, Iran, with atypical dermatosis, pronounced pain, and oedema of the affected tissue. It was confirmed by both conventional and molecular analysis that culture was a mixture of Bacillus anthracis and Trichophyton interdigitale. The patient was initially treated with ceftriaxone (1000 mg/day for two weeks), gentamicin (1.5–2 mg/kg/day), terbinafine (200 mg/week for one month), and 1% clotrimazole cream (5 weeks) two times per day which resulted in gradual improvement. No relapse could be detected after one-year follow-up. Anthrax infection might present a broader spectrum of symptoms than expected by clinicians. These unfamiliar characteristics may lead to delayed diagnosis, inadequate treatment, and higher mortality rate. Clinicians need to be aware of this issue in order to have successful management over this infection. PMID:26451148

  11. Differential effects of linezolid and ciprofloxacin on toxin production by Bacillus anthracis in an in vitro pharmacodynamic system.

    PubMed

    Louie, Arnold; Vanscoy, Brian D; Heine, Henry S; Liu, Weiguo; Abshire, Terry; Holman, Kari; Kulawy, Robert; Brown, David L; Drusano, George L

    2012-01-01

    Bacillus anthracis causes anthrax. Ciprofloxacin is a gold standard for the treatment of anthrax. Previously, using the non-toxin-producing ΔSterne strain of B. anthracis, we demonstrated that linezolid was equivalent to ciprofloxacin for reducing the total (vegetative and spore) bacterial population. With ciprofloxacin therapy, the total population consisted of spores. With linezolid therapy, the population consisted primarily of vegetative bacteria. Linezolid is a protein synthesis inhibitor, while ciprofloxacin is not. Since toxins are produced only by vegetative B. anthracis, the effect of linezolid and ciprofloxacin on toxin production is of interest. The effect of simulated clinical regimens of ciprofloxacin and linezolid on the vegetative and spore populations and on toxin production was examined in an in vitro pharmacodynamic model over 15 days by using the toxin-producing Sterne strain of B. anthracis. Ciprofloxacin and linezolid reduced the total Sterne population at similar rates. With ciprofloxacin therapy, the total Sterne population consisted of spores. With linezolid therapy, >90% of the population was vegetative B. anthracis. With ciprofloxacin therapy, toxin was first detectable at 3 h and remained detectable for at least 5 h. Toxin was never detected with linezolid therapy. Ciprofloxacin and linezolid reduced the total Sterne population at similar rates. However, the B. anthracis population was primarily spores with ciprofloxacin therapy and was primarily vegetative bacteria with linezolid therapy. Toxin production was detected for at least 5 h with ciprofloxacin therapy but was never detected with linezolid treatment. Linezolid may have an advantage over ciprofloxacin for the treatment of B. anthracis infections. PMID:22064542

  12. Radiosurgery for brain metastases and cerebral edema.

    PubMed

    Gazit, Inbal; Har-Nof, Sagi; Cohen, Zvi R; Zibly, Zion; Nissim, Uzi; Spiegelmann, Roberto

    2015-03-01

    The objective of this study was to assess reduction in cerebral edema following linear accelerator radiosurgery (LINAC) as first line therapy for brain metastasis. We reviewed the medical records of all patients who underwent LINAC radiosurgery for brain metastasis at our institution during 2010-2012, and who had not previously undergone either surgery or whole brain radiotherapy. Data were analyzed for 55 brain metastases from 46 patients (24 males), mean age 59.9 years. During the 2 months following LINAC radiosurgery, the mean steroid dose decreased from 4.8 to 2.6 mg/day, the mean metastasis volume decreased from 3.79±4.12 cc to 2.8±4.48 cc (p=0.001), and the mean edema volume decreased from 16.91±30.15 cc to 12.85±24.47 cc (p=0.23). The 17 patients with reductions of more than 50% in brain edema volume had single metastases. Edema volume in the nine patients with two brain metastases remained stable in five patients (volume change <10%, 0-2 cc) and increased in four patients (by >10%, 2-14 cc). In a subanalysis of eight metastases with baseline edema volume greater than 40 cc, edema volume decreased from 77.27±37.21 cc to 24.84±35.6 cc (p=0.034). Reductions in brain edema were greater in metastases for which non-small-cell lung carcinoma and breast cancers were the primary diseases. Overall, symptoms improved in most patients. No patients who were without symptoms or who had no signs of increased intracranial pressure at baseline developed signs of intracranial pressure following LINAC radiosurgery. In this series, LINAC stereotactic radiosurgery for metastatic brain lesions resulted in early reduction in brain edema volume in single metastasis patients and those with large edema volumes, and reduced the need for steroids. PMID:25533053

  13. [The return of anthrax. From bioterrorism to the zoonotic cluster of Sciacca district].

    PubMed

    Scarlata, Francesco; Colletti, Pietro; Bonura, Silvia; Trizzino, Marcello; Giordano, Salvatore; Titone, Lucina

    2010-06-01

    Anthrax is a disease caused by Bacillus anthracis which affects herbivorous animals. Humans acquire the disease incidentally by exposure to infected animals, animal products or spores on soil. The infection is still endemic in many regions in developing countries. In Italy animal clusters are very rare and human cases are exceptional. Bacillus anthrax is also a potential source for acts of bioterrorism. In the natural human infection, cutaneous anthrax is the most widespread, while the other two, pulmonary and gastrointestinal anthrax, are very rare forms. We describe the first case of human anthrax occurring in western Sicily in the last twenty years. The cutaneous lesion healed without significant scarring after antibiotic treatment with tigecycline, rifampin and ciprofloxacin. Following our diagnosis, a cluster of bovine anthrax was detected in the district of Sciacca, causing the death of 13 animals. A larger outbreak was avoided by the vaccination of over 5000 herbivores. PMID:20610930

  14. Melatonin lowers edema after spinal cord injury

    PubMed Central

    Li, Cheng; Chen, Xiao; Qiao, Suchi; Liu, Xinwei; Liu, Chang; Zhu, Degang; Su, Jiacan; Wang, Zhiwei

    2014-01-01

    Melatonin has been shown to diminish edema in rats. Melatonin can be used to treat spinal cord injury. This study presumed that melatonin could relieve spinal cord edema and examined how it might act. Our experiments found that melatonin (100 mg/kg, i.p.) could reduce the water content of the spinal cord, and suppress the expression of aquaporin-4 and glial fibrillary acidic protein after spinal cord injury. This suggests that the mechanism by which melatonin alleviates the damage to the spinal cord by edema might be related to the expression of aquaporin-4 and glial fibrillary acidic protein. PMID:25657743

  15. Alpha-toxin of Staphylococcus aureus.

    PubMed Central

    Bhakdi, S; Tranum-Jensen, J

    1991-01-01

    Alpha-toxin, the major cytotoxic agent elaborated by Staphylococcus aureus, was the first bacterial exotoxin to be identified as a pore former. The protein is secreted as a single-chain, water-soluble molecule of Mr 33,000. At low concentrations (less than 100 nM), the toxin binds to as yet unidentified, high-affinity acceptor sites that have been detected on a variety of cells including rabbit erythrocytes, human platelets, monocytes and endothelial cells. At high concentrations, the toxin additionally binds via nonspecific absorption to lipid bilayers; it can thus damage both cells lacking significant numbers of the acceptor and protein-free artificial lipid bilayers. Membrane damage occurs in both cases after membrane-bound toxin molecules collide via lateral diffusion to form ring-structured hexamers. The latter insert spontaneously into the lipid bilayer to form discrete transmembrane pores of effective diameter 1 to 2 nm. A hypothetical model is advanced in which the pore is lined by amphiphilic beta-sheets, one surface of which interacts with lipids whereas the other repels apolar membrane constitutents to force open an aqueous passage. The detrimental effects of alpha-toxin are due not only to the death of susceptible targets, but also to the presence of secondary cellular reactions that can be triggered via Ca2+ influx through the pores. Well-studied phenomena include the stimulation of arachidonic acid metabolism, triggering of granule exocytosis, and contractile dysfunction. Such processes cause profound long-range disturbances such as development of pulmonary edema and promotion of blood coagulation.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:1779933

  16. Pharmacological investigation of the nociceptive response and edema induced by venom of the scorpion Tityus serrulatus.

    PubMed

    Nascimento, Elias B; Costa, Karina A; Bertollo, Caryne M; Oliveira, Antônio Carlos P; Rocha, Leonardo T S; Souza, Adriano L S; Glória, Maria Beatriz A; Moraes-Santos, Tasso; Coelho, Márcio M

    2005-04-01

    In this study we characterized the nociceptive response and edema induced by the venom of the scorpion Tityus serrulatus in rats and mice and carried out a preliminary pharmacological investigation of the mechanisms involved in these responses. Intraplantar injection of the venom (1 or 10mug) induced edema and a marked ipsilateral nociceptive response, characterized by thermal and mechanical allodynia and paw licking behaviour. The nociceptive response was inhibited by previous intraperitoneal administration of indomethacin (4mg/kg), dipyrone (200mg/kg), cyproheptadine (10mg/kg) or morphine (5 or 10mg/kg), but not by dexamethasone (1 or 4mg/kg) or promethazine (1 or 5mg/kg). The edema was inhibited by previous treatment with promethazine (5 or 10mg/kg) or cyproheptadine (5 or 10mg/kg), but not by indomethacin (2 or 4mg/kg), dexamethasone (1 or 4mg/kg) or cromolyn (40 or 80mg/kg). Some bioactive amines, including histamine and 5-hydroxytryptamine, were found in the venom in low concentrations. In conclusion, the nociceptive response and edema induced by the venom of T. serrulatus may result from the action of multiple mediators including eicosanoids, histamine and 5-hydroxytryptamine. These results may lead to a better understanding of the host response to potent animal toxins and also give insights into a more rational pharmacological approach to alleviate the intense pain associated with the scorpion envenomation. PMID:15777954

  17. Confirmation of Bacillus anthracis from flesh-eating flies collected during a West Texas anthrax season.

    PubMed

    Blackburn, Jason K; Curtis, Andrew; Hadfield, Ted L; O'Shea, Bob; Mitchell, Mark A; Hugh-Jones, Martin E

    2010-07-01

    This case study confirms the interaction between necrophilic flies and white-tailed deer, Odocoileus virginianus, during an anthrax outbreak in West Texas (summer 2005). Bacillus anthracis was identified by culture and PCR from one of eight pooled fly collections from deer carcasses on a deer ranch with a well-documented history of anthrax. These results provide the first known isolation of B. anthracis from flesh-eating flies associated with a wildlife anthrax outbreak in North America and are discussed in the context of wildlife ecology and anthrax epizootics. PMID:20688697

  18. Integrated MOSFET-Embedded-Cantilever-Based Biosensor Characteristic for Detection of Anthrax Simulant

    SciTech Connect

    Mostafa, Salwa; Lee, Ida; Islam, Syed K; Eliza, Sazia A.; Shekhawat, Gajendra; Dravid, Vinayak; Tulip, Fahmida S

    2011-01-01

    In this work, MOSFET-embedded cantilevers are configured as microbial sensors for detection of anthrax simulants, Bacillus thuringiensis. Anthrax simulants attached to the chemically treated gold-coated cantilever cause changes in the MOSFET drain current due to the bending of the cantilever which indicates the detection of anthrax simulant. Electrical properties of the anthrax simulant are also responsible for the change in the drain current. The test results suggest a detection range of 10 L of stimulant test solution (a suspension population of 1.3 107 colony-forming units/mL diluted in 40% ethanol and 60% deionized water) with a linear response of 31 A/ L.

  19. Perspectives on edema in childhood nephrotic syndrome.

    PubMed

    Teoh, Chia Wei; Robinson, Lisa A; Noone, Damien

    2015-10-01

    There have been two major theories surrounding the development of edema in nephrotic syndrome (NS), namely, the under- and overfill hypotheses. Edema is one of the cardinal features of NS and remains one of the principal reasons for admission of children to the hospital. Recently, the discovery that proteases in the glomerular filtrate of patients with NS are activating the epithelial sodium channel (ENaC), resulting in intrarenal salt retention and thereby contributing to edema, might suggest that targeting ENaC with amiloride might be a suitable strategy to manage the edema of NS. Other potential agents, particularly urearetics and aquaretics, might also prove useful in NS. Recent evidence also suggests that there may be other areas involved in salt storage, especially the skin, and it will be intriguing to study the implications of this in NS. PMID:26290369

  20. Pedal edema associated with atypical antipsychotics

    PubMed Central

    Munshi, Santanu; Mukherjee, Shatavisa; Saha, Indranil; Sen, Sukanta

    2016-01-01

    This study describes a patient diagnosed as a case of bipolar affective disorder complaining of bothersome incidence of pedal edema 1 month after the initiation of atypical antipsychotic regimen with risperidone and quetiapine. All hematological and biochemical profiles were found to be normal. On discontinuation of risperidone, the condition remained unresolved even after 2 weeks, and the edema progressed reaching her calves. On tapering the dose of quetiapine, she started showing gradual improvement in edematous condition. Quetiapine was slowly discontinued. No further recurrence of edema occurred, and hence, no further medication changes were implemented. Pedal edema was found to be resolved within weeks of dechallenge of the regimen. Naranjo adverse drug reaction probability scale gave a score of 7 which denotes “probable” adverse drug reaction with quetiapine. PMID:26997731

  1. Ankylosing spondylitis is associated with the anthrax toxin receptor 2 gene (ANTXR2)

    PubMed Central

    Karaderi, T; Keidel, S M; Pointon, J J; Appleton, L H; Brown, M A; Evans, D M; Wordsworth, B P

    2014-01-01

    Objectives ANTXR2 variants have been associated with ankylosing spondylitis (AS) in two previous genome-wide association studies (GWAS) (p∼9×10−8). However, a genome-wide significant association (p<5×10−8) was not observed. We conducted a more comprehensive analysis of ANTXR2 in an independent UK sample to confirm and refine this association. Methods A replication study was carried out with 2978 cases and 8365 controls. Then, these were combined with non-overlapping samples from the two previous GWAS in a meta-analysis. Human leukocyte antigen (HLA)-B27 stratification was also performed to test for ANTXR2-HLA-B27 interaction. Results Out of nine single nucleotide polymorphisms (SNP) in the study, five SNPs were nominally associated (p<0.05) with AS in the replication dataset. In the meta-analysis, eight SNPs showed evidence of association, the strongest being with rs12504282 (OR=0.88, p=6.7×10−9). Seven of these SNPs showed evidence for association in the HLA-B27-positive subgroup, but none was associated with HLA-B27-negative AS. However, no statistically significant interaction was detected between HLA-B27 and ANTXR2 variants. Conclusions ANTXR2 variants are clearly associated with AS. The top SNPs from two previous GWAS (rs4333130 and rs4389526) and this study (rs12504282) are in strong linkage disequilibrium (r2≥0.76). All are located near a putative regulatory region. Further studies are required to clarify the role played by these ANTXR2 variants in AS. PMID:25169729

  2. Efficacy and Immunogenicity of Single-Dose AdVAV Intranasal Anthrax Vaccine Compared to Anthrax Vaccine Absorbed in an Aerosolized Spore Rabbit Challenge Model

    PubMed Central

    Krishnan, Vyjayanthi; Andersen, Bo H.; Shoemaker, Christine; Sivko, Gloria S.; Tordoff, Kevin P.; Stark, Gregory V.; Zhang, Jianfeng; Feng, Tsungwei; Duchars, Matthew

    2015-01-01

    AdVAV is a replication-deficient adenovirus type 5-vectored vaccine expressing the 83-kDa protective antigen (PA83) from Bacillus anthracis that is being developed for the prevention of disease caused by inhalation of aerosolized B. anthracis spores. A noninferiority study comparing the efficacy of AdVAV to the currently licensed Anthrax Vaccine Absorbed (AVA; BioThrax) was performed in New Zealand White rabbits using postchallenge survival as the study endpoint (20% noninferiority margin for survival). Three groups of 32 rabbits were vaccinated with a single intranasal dose of AdVAV (7.5 × 107, 1.5 × 109, or 3.5 × 1010 viral particles). Three additional groups of 32 animals received two doses of either intranasal AdVAV (3.5 × 1010 viral particles) or intramuscular AVA (diluted 1:16 or 1:64) 28 days apart. The placebo group of 16 rabbits received a single intranasal dose of AdVAV formulation buffer. All animals were challenged via the inhalation route with a targeted dose of 200 times the 50% lethal dose (LD50) of aerosolized B. anthracis Ames spores 70 days after the initial vaccination and were followed for 3 weeks. PA83 immunogenicity was evaluated by validated toxin neutralizing antibody and serum anti-PA83 IgG enzyme-linked immunosorbent assays (ELISAs). All animals in the placebo cohort died from the challenge. Three of the four AdVAV dose cohorts tested, including two single-dose cohorts, achieved statistical noninferiority relative to the AVA comparator group, with survival rates between 97% and 100%. Vaccination with AdVAV also produced antibody titers with earlier onset and greater persistence than vaccination with AVA. PMID:25673303

  3. Efficacy and immunogenicity of single-dose AdVAV intranasal anthrax vaccine compared to anthrax vaccine absorbed in an aerosolized spore rabbit challenge model.

    PubMed

    Krishnan, Vyjayanthi; Andersen, Bo H; Shoemaker, Christine; Sivko, Gloria S; Tordoff, Kevin P; Stark, Gregory V; Zhang, Jianfeng; Feng, Tsungwei; Duchars, Matthew; Roberts, M Scot

    2015-04-01

    AdVAV is a replication-deficient adenovirus type 5-vectored vaccine expressing the 83-kDa protective antigen (PA83) from Bacillus anthracis that is being developed for the prevention of disease caused by inhalation of aerosolized B. anthracis spores. A noninferiority study comparing the efficacy of AdVAV to the currently licensed Anthrax Vaccine Absorbed (AVA; BioThrax) was performed in New Zealand White rabbits using postchallenge survival as the study endpoint (20% noninferiority margin for survival). Three groups of 32 rabbits were vaccinated with a single intranasal dose of AdVAV (7.5 × 10(7), 1.5 × 10(9), or 3.5 × 10(10) viral particles). Three additional groups of 32 animals received two doses of either intranasal AdVAV (3.5 × 10(10) viral particles) or intramuscular AVA (diluted 1:16 or 1:64) 28 days apart. The placebo group of 16 rabbits received a single intranasal dose of AdVAV formulation buffer. All animals were challenged via the inhalation route with a targeted dose of 200 times the 50% lethal dose (LD50) of aerosolized B. anthracis Ames spores 70 days after the initial vaccination and were followed for 3 weeks. PA83 immunogenicity was evaluated by validated toxin neutralizing antibody and serum anti-PA83 IgG enzyme-linked immunosorbent assays (ELISAs). All animals in the placebo cohort died from the challenge. Three of the four AdVAV dose cohorts tested, including two single-dose cohorts, achieved statistical noninferiority relative to the AVA comparator group, with survival rates between 97% and 100%. Vaccination with AdVAV also produced antibody titers with earlier onset and greater persistence than vaccination with AVA. PMID:25673303

  4. Transient Corneal Edema is a Predictive Factor for Pseudophakic Cystoid Macular Edema after Uncomplicated Cataract Surgery

    PubMed Central

    Do, Jae Rock; Oh, Jong-Hyun; Chuck, Roy S.

    2015-01-01

    Purpose To report transient corneal edema after phacoemulsification as a predictive factor for the development of pseudophakic cystoid macular edema (PCME). Methods A total of 150 eyes from 150 patients (59 men and 91 women; mean age, 68.0 ± 10.15 years) were analyzed using spectral domain optical coherence tomography 1 week and 5 weeks after routine phacoemulsification cataract surgery. Transient corneal edema detected 1 week after surgery was analyzed to reveal any significant relationship with the development of PCME 5 weeks after surgery. Results Transient corneal edema developed in 17 (11.3%) of 150 eyes 1 week after surgery. A history of diabetes mellitus was significantly associated with development of transient corneal edema (odds ratio [OR], 4.04; 95% confidence interval [CI], 1.41 to 11.54; p = 0.011). Both diabetes mellitus and transient corneal edema were significantly associated with PCME development 5 weeks after surgery (OR, 4.58; 95% CI, 1.56 to 13.43; p = 0.007; and OR, 6.71; CI, 2.05 to 21.95; p = 0.003, respectively). In the 8 eyes with both diabetes mellitus and transient corneal edema, 4 (50%) developed PCME 5 weeks after surgery. Conclusions Transient corneal edema detected 1 week after routine cataract surgery is a predictive factor for development of PCME. Close postoperative observation and intervention is recommended in patients with transient corneal edema. PMID:25646056

  5. Brain edema in diseases of different etiology.

    PubMed

    Adeva, María M; Souto, Gema; Donapetry, Cristóbal; Portals, Manuel; Rodriguez, Alberto; Lamas, David

    2012-07-01

    Cerebral edema is a potentially life-threatening complication shared by diseases of different etiology, such as diabetic ketoacidosis, acute liver failure, high altitude exposure, dialysis disequilibrium syndrome, and salicylate intoxication. Pulmonary edema is also habitually present in these disorders, indicating that the microcirculatory disturbance causing edema is not confined to the brain. Both cerebral and pulmonary subclinical edema may be detected before it becomes clinically evident. Available evidence suggests that tissue hypoxia or intracellular acidosis is a commonality occurring in all of these disorders. Tissue ischemia induces physiological compensatory mechanisms to ensure cell oxygenation and carbon dioxide removal from tissues, including hyperventilation, elevation of red blood cell 2,3-bisphosphoglycerate content, and capillary vasodilatation. Clinical, laboratory, and necropsy findings in these diseases confirm the occurrence of low plasma carbon dioxide partial pressure, increased erythrocyte 2,3-bisphosphoglycerate concentration, and capillary vasodilatation with increased vascular permeability in all of them. Baseline tissue hypoxia or intracellular acidosis induced by the disease may further deteriorate when tissue oxygen requirement is no longer matched to oxygen delivery resulting in massive capillary vasodilatation with increased vascular permeability and plasma fluid leakage into the interstitial compartment leading to edema affecting the brain, lung, and other organs. Causative factors involved in the progression from physiological adaptation to devastating clinical edema are not well known and may include uncontrolled disease, malfunctioning adaptive responses, or unknown factors. The role of carbon monoxide and local nitric oxide production influencing tissue oxygenation is unclear. PMID:22579570

  6. [Intoxication of botulinum toxin].

    PubMed

    Chudzicka, Aleksandra

    2015-09-01

    Botulinum toxin is an egzotoxin produced by Gram positive bacteria Clostridium botulinum. It is among the most potent toxins known. The 3 main clinical presentations of botulism are as follows: foodborne botulism, infant botulism and wound botulism. The main symptom of intoxication is flat muscles paralysis. The treatment is supportive care and administration of antitoxin. In prevention the correct preparing of canned food is most important. Botulinum toxin is accepted as a biological weapon. PMID:26449577

  7. Olanzapine-induced tender pitting pre-tibial edema.

    PubMed

    Mathan, Kaliaperumal; Muthukrishnan, Venkatesan; Menon, Vikas

    2015-01-01

    Antipsychotic-induced edema is uncommonly encountered in clinical practice. We report a case of tender pitting pre-tibial edema with olanzapine in a woman with no medical comorbidities. The peculiar distribution of edema resulted in diagnostic confusion necessitating specific investigations. Eventually, the edema resolved following complete stoppage of the drug, but caused distress to the patient and the caregiver. PMID:25969664

  8. Impedance spectroscopy for the detection and identification of unknown toxins

    NASA Astrophysics Data System (ADS)

    Riggs, B. C.; Plopper, G. E.; Paluh, J. L.; Phamduy, T. B.; Corr, D. T.; Chrisey, D. B.

    2012-06-01

    Advancements in biological and chemical warfare has allowed for the creation of novel toxins necessitating a universal, real-time sensor. We have used a function-based biosensor employing impedance spectroscopy using a low current density AC signal over a range of frequencies (62.5 Hz-64 kHz) to measure the electrical impedance of a confluent epithelial cell monolayer at 120 sec intervals. Madin Darby canine kidney (MDCK) epithelial cells were grown to confluence on thin film interdigitated gold electrodes. A stable impedance measurement of 2200 Ω was found after 24 hrs of growth. After exposure to cytotoxins anthrax lethal toxin and etoposide, the impedance decreased in a linear fashion resulting in a 50% drop in impedance over 50hrs showing significant difference from the control sample (~20% decrease). Immunofluorescent imaging showed that apoptosis was induced through the addition of toxins. Similarities of the impedance signal shows that the mechanism of cellular death was the same between ALT and etoposide. A revised equivalent circuit model was employed in order to quantify morphological changes in the cell monolayer such as tight junction integrity and cell surface area coverage. This model showed a faster response to cytotoxin (2 hrs) compared to raw measurements (20 hrs). We demonstrate that herein that impedance spectroscopy of epithelial monolayers serves as a real-time non-destructive sensor for unknown pathogens.

  9. Public response to an anthrax attack: a multiethnic perspective.

    PubMed

    Steelfisher, Gillian K; Blendon, Robert J; Brulé, Amanda S; Ben-Porath, Eran N; Ross, Laura J; Atkins, Bret M

    2012-12-01

    The 2001 anthrax attacks emphasized the need to develop outreach that would more effectively support racial/ethnic minority populations during a bioterrorism incident. Given the importance of antibiotic prophylaxis in a future anthrax attack, it should be a priority to better support racial/ethnic minorities in mass dispensing programs. To examine the needs and perspectives of racial/ethnic minorities, this study used a nationally representative poll of 1,852 adults, including 1,240 whites, 261 African Americans, and 282 Hispanics. The poll examined public reactions to a ''worst-case scenario'' in which cases of inhalation anthrax are discovered without an identified source and the entire population of a city or town is asked to receive antibiotic prophylaxis within 48 hours. Findings suggest willingness across all racial/ethnic groups to comply with recommendations to seek prophylaxis at dispensing sites. However, findings also indicate possible barriers for racial/ethnic minorities, including greater concern about pill safety and multiple attacks as well as lesser knowledge about inhalation anthrax. Across all racial/ethnic groups, roughly half would prefer to receive antibiotics at mass dispensing sites rather than through the US Postal Service. People in racial/ethnic minority groups were more likely to say this preference stems from a desire to speak with staff or to exchange medication formulation or type. Findings suggest the need for tailored outreach to racial/ethnic minorities through, for example, emphasis on key messages and enhanced understandability in communications, increased staff for answering questions in relevant dispensing sites, and long-term trust building with racial/ethnic minority communities. PMID:23244501

  10. Economic Impacts of a Wide Area Release of Anthrax

    SciTech Connect

    Judd, Kathleen S.; Olson, Jarrod; Stein, Steven L.; Lesperance, Ann M.

    2009-05-29

    This analysis explores economic impacts that might result from a wide-area release of anthrax. The intent is not to provide a quantitative analysis of such a disaster, but to: 1. Define the general categories of economic impacts that the region should be concerned about; and, 2. Explore what types of private sector businesses or industries, if any, may have the greatest impact on speeding the economic recovery of the region.

  11. Public Response to an Anthrax Attack: A Multiethnic Perspective

    PubMed Central

    SteelFisher, Gillian K.; Blendon, Robert J.; Brulé, Amanda S.; Ben-Porath, Eran N.; Ross, Laura J.; Atkins, Bret M.

    2016-01-01

    The 2001 anthrax attacks emphasized the need to develop outreach that would more effectively support racial/ethnic minority populations during a bioterrorism incident. Given the importance of antibiotic prophylaxis in a future anthrax attack, it should be a priority to better support racial/ethnic minorities in mass dispensing programs. To examine the needs and perspectives of racial/ethnic minorities, this study used a nationally representative poll of 1,852 adults, including 1,240 whites, 261 African Americans, and 282 Hispanics. The poll examined public reactions to a “worst-case scenario” in which cases of inhalation anthrax are discovered without an identified source and the entire population of a city or town is asked to receive antibiotic prophylaxis within 48 hours. Findings suggest willingness across all racial/ethnic groups to comply with recommendations to seek prophylaxis at dispensing sites. However, findings also indicate possible barriers for racial/ethnic minorities, including greater concern about pill safety and multiple attacks as well as lesser knowledge about inhalation anthrax. Across all racial/ethnic groups, roughly half would prefer to receive antibiotics at mass dispensing sites rather than through the US Postal Service. People in racial/ethnic minority groups were more likely to say this preference stems from a desire to speak with staff or to exchange medication formulation or type. Findings suggest the need for tailored outreach to racial/ethnic minorities through, for example, emphasis on key messages and enhanced understandability in communications, increased staff for answering questions in relevant dispensing sites, and long-term trust building with racial/ethnic minority communities. PMID:23244501

  12. Botulinum toxin injection - larynx

    MedlinePlus

    Injection laryngoplasty; Botox-larynx: spasmodic dysphonia-BTX; Essential voice tremor (EVT)-btx; Glottic insufficiency; Percutaneous electromyography-guided botulinum toxin treatment; Percutaneous indirect laryngoscopy- ...

  13. Human Anthrax Transmission at the Urban-Rural Interface, Georgia.

    PubMed

    Kracalik, Ian; Malania, Lile; Imnadze, Paata; Blackburn, Jason K

    2015-12-01

    Human anthrax has increased dramatically in Georgia and was recently linked to the sale of meat in an urban market. We assessed epidemiological trends and risk factors for human anthrax at the urban-rural interface. We reviewed epidemiologic records (2000-2012) that included the place of residence (classified as urban, peri-urban, or rural), age, gender, and self-reported source of infection (handling or processing animal by-products and slaughtering or butchering livestock). To estimate risk, we used a negative binomial regression. The average incidence per 1 million population in peri-urban areas (24.5 cases) was > 2-fold higher compared with rural areas and > 3-fold higher compared with urban area. Risk from handling or purchasing meat was nearly 2-fold higher in urban areas and > 4-fold higher in peri-urban areas compared with rural area. Our findings suggest a high risk of anthrax in urban and peri-urban areas likely as a result of spillover from contaminated meat and animal by-products. Consumers should be warned to purchase meat only from licensed merchants. PMID:26438026

  14. HEPA/vaccine plan for indoor anthrax remediation.

    PubMed

    Wein, Lawrence M; Liu, Yifan; Leighton, Terrance J

    2005-01-01

    We developed a mathematical model to compare 2 indoor remediation strategies in the aftermath of an outdoor release of 1.5 kg of anthrax spores in lower Manhattan. The 2 strategies are the fumigation approach used after the 2001 postal anthrax attack and a HEPA/vaccine plan, which relies on HEPA vacuuming, HEPA air cleaners, and vaccination of reoccupants. The HEPA/vaccine approach leads to few anthrax cases among reoccupants if applied to all but the most heavily contaminated buildings, and recovery is much faster than under the decades-long fumigation plan. Only modest environmental sampling is needed. A surge capacity of 10,000 to 20,000 Hazmat workers is required to perform remediation within 6 to 12 months and to avoid permanent mass relocation. Because of the possibility of a campaign of terrorist attacks, serious consideration should be given to allowing or encouraging voluntary self-service cleaning of lightly contaminated rooms by age-appropriate, vaccinated, partially protected (through masks or hoods) reoccupants or owners. PMID:15705325

  15. Human Anthrax Transmission at the Urban–Rural Interface, Georgia

    PubMed Central

    Kracalik, Ian; Malania, Lile; Imnadze, Paata; Blackburn, Jason K.

    2015-01-01

    Human anthrax has increased dramatically in Georgia and was recently linked to the sale of meat in an urban market. We assessed epidemiological trends and risk factors for human anthrax at the urban–rural interface. We reviewed epidemiologic records (2000–2012) that included the place of residence (classified as urban, peri-urban, or rural), age, gender, and self-reported source of infection (handling or processing animal by-products and slaughtering or butchering livestock). To estimate risk, we used a negative binomial regression. The average incidence per 1 million population in peri-urban areas (24.5 cases) was > 2-fold higher compared with rural areas and > 3-fold higher compared with urban area. Risk from handling or purchasing meat was nearly 2-fold higher in urban areas and > 4-fold higher in peri-urban areas compared with rural area. Our findings suggest a high risk of anthrax in urban and peri-urban areas likely as a result of spillover from contaminated meat and animal by-products. Consumers should be warned to purchase meat only from licensed merchants. PMID:26438026

  16. HEPA/Vaccine Plan for Indoor Anthrax Remediation

    PubMed Central

    Liu, Yifan; Leighton, Terrance J.

    2005-01-01

    We developed a mathematical model to compare 2 indoor remediation strategies in the aftermath of an outdoor release of 1.5 kg of anthrax spores in lower Manhattan. The 2 strategies are the fumigation approach used after the 2001 postal anthrax attack and a HEPA/vaccine plan, which relies on HEPA vacuuming, HEPA air cleaners, and vaccination of reoccupants. The HEPA/vaccine approach leads to few anthrax cases among reoccupants if applied to all but the most heavily contaminated buildings, and recovery is much faster than under the decades-long fumigation plan. Only modest environmental sampling is needed. A surge capacity of 10,000 to 20,000 Hazmat workers is required to perform remediation within 6 to 12 months and to avoid permanent mass relocation. Because of the possibility of a campaign of terrorist attacks, serious consideration should be given to allowing or encouraging voluntary self-service cleaning of lightly contaminated rooms by age-appropriate, vaccinated, partially protected (through masks or hoods) reoccupants or owners. PMID:15705325

  17. Space Technology to Device That Destroys Pathogens Such as Anthrax

    NASA Technical Reports Server (NTRS)

    2002-01-01

    AiroCide Ti02, an anthrax-killing air scrubber manufactured by KES Science and Technology Inc., in Kernesaw, Georgia, looks like a square metal box when it is installed on an office wall. Its fans draw in airborne spores and airflow forces them through a maze of tubes. Inside, hydroxyl radicals (OH-) attack and kill pathogens. Most remaining spores are destroyed by high-energy ultraviolet photons. Building miniature greenhouses for experiments on the International Space Station (ISS) has led to the invention of this device that annihilates anthrax-a bacteria that can be deadly when inhaled. The research enabling the invention started at the University of Wisconsin (Madison) Center for Space Automation and Robotics (WCSAR), one of 17 NASA Commercial Space Centers. A special coating technology used in the anthrax-killing invention is also being used inside WCSAR-built plant growth units on the ISS. This commercial research is managed by the Space Product Development Program at the Marshall Space Flight Center.

  18. Interactions between Bacillus anthracis and Plants May Promote Anthrax Transmission

    PubMed Central

    Ganz, Holly H.; Turner, Wendy C.; Brodie, Eoin L.; Kusters, Martina; Shi, Ying; Sibanda, Heniritha; Torok, Tamas; Getz, Wayne M.

    2014-01-01

    Environmental reservoirs are essential in the maintenance and transmission of anthrax but are poorly characterized. The anthrax agent, Bacillus anthracis was long considered an obligate pathogen that is dormant and passively transmitted in the environment. However, a growing number of laboratory studies indicate that, like some of its close relatives, B. anthracis has some activity outside of its vertebrate hosts. Here we show in the field that B. anthracis has significant interactions with a grass that could promote anthrax spore transmission to grazing hosts. Using a local, virulent strain of B. anthracis, we performed a field experiment in an enclosure within a grassland savanna. We found that B. anthracis increased the rate of establishment of a native grass (Enneapogon desvauxii) by 50% and that grass seeds exposed to blood reached heights that were 45% taller than controls. Further we detected significant effects of E. desvauxii, B. anthracis, and their interaction on soil bacterial taxa richness and community composition. We did not find any evidence for multiplication or increased longevity of B. anthracis in bulk soil associated with grass compared to controls. Instead interactions between B. anthracis and plants may result in increased host grazing and subsequently increased transmission to hosts. PMID:24901846

  19. Appropriation and commercialization of the Pasteur anthrax vaccine.

    PubMed

    Cassier, Maurice

    2005-12-01

    Whereas Pasteur patented the biotechnological processes that he invented between 1857 and 1873 in the agro-food domain, he did not file any patents on the artificial vaccine preparation processes that he subsequently developed. This absence of patents can probably be explained by the 1844 patent law in France that established the non-patentable status of pharmaceutical preparations and remedies, including those for use in veterinary medicine. Despite the absence of patents, the commercial exploitation of the anthrax vaccine in the 1880s and 1890s led to a technical and commercial monopoly by Pasteur's laboratory as well as the founding of a commercial company to diffuse the vaccine abroad. Pasteur repeatedly refused to transfer his know-how and anthrax vaccine production methods to foreign laboratories, on the grounds that he wished to control the quality of the vaccines produced. Indeed, it was relatively difficult to transfer a method that was not yet perfectly stabilized in the early 1880s. Pasteur also wanted to maintain the monopoly of his commercial company and to increase the profits from vaccine sales so that the Institut Pasteur could be financially independent. The 'Pasteur anthrax vaccine' operating licences are described and analysed in detail in this article. PMID:16337558

  20. 9 CFR 309.7 - Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Livestock affected with anthrax... INSPECTION § 309.7 Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways. (a) Any livestock found on ante-mortem inspection to be affected with anthrax shall be...

  1. 9 CFR 309.7 - Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Livestock affected with anthrax... INSPECTION § 309.7 Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways. (a) Any livestock found on ante-mortem inspection to be affected with anthrax shall be...

  2. 9 CFR 309.7 - Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Livestock affected with anthrax... INSPECTION § 309.7 Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways. (a) Any livestock found on ante-mortem inspection to be affected with anthrax shall be...

  3. 9 CFR 309.7 - Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Livestock affected with anthrax... INSPECTION § 309.7 Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways. (a) Any livestock found on ante-mortem inspection to be affected with anthrax shall be...

  4. 9 CFR 309.7 - Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Livestock affected with anthrax... INSPECTION § 309.7 Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways. (a) Any livestock found on ante-mortem inspection to be affected with anthrax shall be...

  5. Identification of peptide sequences as a measure of Anthrax vaccine stability during storage.

    PubMed

    Whiting, Gail; Wheeler, Jun X; Rijpkema, Sjoerd

    2014-01-01

    The UK anthrax vaccine is an alum precipitate of a sterile filtrate of Bacillus anthracis Sterne culture (AVP). An increase in shelf life of AVP from 3 to 5 years prompted us to investigate the in vivo potency and the antigen content of 12 batches with a shelf life of 6.4 to 9.9 years and one bulk with a shelf life of 23.8 years. All batches, except for a 9.4-year-old batch, passed the potency test. Mass spectrometry (MS) and in-gel difference 2-dimensional gel electrophoresis (DIGE) were used to examine antigens of the pellet and supernatant of AVP. The pellet contained proteins with a MW in excess of 15 kDa. DIGE of desorbed proteins from the pellet revealed that with aging, 19 spots showed a significant change in size or intensity, a sign of protein degradation. MS identified 21 proteins including protective antigen (PA), enolase, lethal factor (LF), nucleoside diphosphate kinase, edema factor, and S-layer proteins. Fifteen proteins were detected for the first time including metabolic enzymes, iron binding proteins, and manganese dependent superoxide dismutase (MnSOD). The supernatant contained131 peptide sequences. Peptides representing septum formation inhibitor protein and repeat domain protein were most abundant. Five proteins were shared with the pellet: 2,3,4,5-tetrahydropyridine-6-dicarboxylate N-succinyltransferase, enolase, LF, MnSOD, and PA. The number of peptide sequences increased with age. Peptides from PA and LF appeared once batches exceeded their shelf life by 2 and 4 years, respectively. In conclusion, changes in antigen content resulting from decay or desorption only had a limited effect on in vivo potency of AVP. The presence of PA and LF peptides in the supernatant can inform on the age and stability of AVP. PMID:24637775

  6. Antibody responses to a spore carbohydrate antigen as a marker of nonfatal inhalation anthrax in rhesus macaques.

    PubMed

    Saile, Elke; Boons, Geert-Jan; Buskas, Therese; Carlson, Russell W; Kannenberg, Elmar L; Barr, John R; Boyer, Anne E; Gallegos-Candela, Maribel; Quinn, Conrad P

    2011-05-01

    The Bacillus anthracis exosporium protein BclA contains an O-linked antigenic tetrasaccharide whose terminal sugar is known as anthrose (J. M. Daubenspeck et al., J. Biol. Chem. 279:30945-30953, 2004). We hypothesized that serologic responses to anthrose may have diagnostic value in confirming exposure to aerosolized B. anthracis. We evaluated the serologic responses to a synthetic anthrose-containing trisaccharide (ATS) in a group of five rhesus macaques that survived inhalation anthrax following exposure to B. anthracis Ames spores. Two of five animals (RM2 and RM3) were treated with ciprofloxacin starting at 48 hours postexposure and two (RM4 and RM5) at 72 h postexposure; one animal (RM1) was untreated. Infection was confirmed by blood culture and detection of anthrax toxin lethal factor (LF) in plasma. Anti-ATS IgG responses were determined at 14, 21, 28, and 35 days postexposure, with preexposure serum as a control. All animals, irrespective of ciprofloxacin treatment, mounted a specific, measurable anti-ATS IgG response. The earliest detectable responses were on days 14 (RM1, RM2, and RM5), 21 (RM4), and 28 (RM3). Specificity of the anti-ATS responses was demonstrated by competitive-inhibition enzyme immunoassay (CIEIA), in which a 2-fold (wt/wt) excess of carbohydrate in a bovine serum albumin (BSA) conjugate of the oligosaccharide (ATS-BSA) effected >94% inhibition, whereas a structural analog lacking the 3-hydroxy-3-methyl-butyryl moiety at the C-4" of the anthrosyl residue had no inhibition activity. These data suggest that anti-ATS antibody responses may be used to identify aerosol exposure to B. anthracis spores. The anti-ATS antibody responses were detectable during administration of ciprofloxacin. PMID:21389148

  7. Recombinant vaccine displaying the loop-neutralizing determinant from protective antigen completely protects rabbits from experimental inhalation anthrax.

    PubMed

    Oscherwitz, Jon; Yu, Fen; Jacobs, Jana L; Cease, Kemp B

    2013-03-01

    We previously showed that a multiple antigenic peptide (MAP) vaccine displaying amino acids (aa) 304 to 319 from the 2β2-2β3 loop of protective antigen was capable of protecting rabbits from an aerosolized spore challenge with Bacillus anthracis Ames strain. Antibodies to this sequence, referred to as the loop-neutralizing determinant (LND), are highly potent at neutralizing lethal toxin yet are virtually absent in rabbit and human protective antigen (PA) antiserum. While the MAP vaccine was protective against anthrax, it contains a single heterologous helper T cell epitope which may be suboptimal for stimulating an outbred human population. We therefore engineered a recombinant vaccine (Rec-LND) containing two tandemly repeated copies of the LND fused to maltose binding protein, with enhanced immunogenicity resulting from the p38/P4 helper T cell epitope from Schistosoma mansoni. Rec-LND was found to be highly immunogenic in four major histocompatibility complex (MHC)-diverse strains of mice. All (7/7) rabbits immunized with Rec-LND developed high-titer antibody, 6 out of 7 developed neutralizing antibody, and all rabbits were protected from an aerosolized spore challenge of 193 50% lethal doses (LD(50)) of the B. anthracis Ames strain. Survivor serum from Rec-LND-immunized rabbits revealed significantly increased neutralization titers and specific activity compared to prechallenge levels yet lacked PA or lethal factor (LF) antigenemia. Control rabbits immunized with PA, which were also completely protected, appeared sterilely immune, exhibiting significant declines in neutralization titer and specific activity compared to prechallenge levels. We conclude that Rec-LND may represent a prototype anthrax vaccine for use alone or potentially combined with PA-containing vaccines. PMID:23283638

  8. Anthracimycin, a potent anthrax antibiotic from a marine-derived actinomycete.

    PubMed

    Jang, Kyoung Hwa; Nam, Sang-Jip; Locke, Jeffrey B; Kauffman, Christopher A; Beatty, Deanna S; Paul, Lauren A; Fenical, William

    2013-07-22

    Licensed to kill: A new antibiotic, anthracimycin (see scheme), produced by a marine-derived actinomycete in saline culture, shows significant activity toward Bacillus anthracis, the bacterial pathogen responsible for anthrax infections. Chlorination of anthracimycin gives a dichloro derivative that retains activity against Gram-positive bacteria, such as anthrax, but also shows activity against selected Gram-negative bacteria. PMID:23776159

  9. Case Report of an Anthrax Presentation Relevant to Special Operations Medicine.

    PubMed

    Winkler, Stephen; Enzenauer, Robert W; Karesh, James W; Pasteur, Nshimyimana; Eisnor, Derek L; Painter, Rex B; Calvano, Christopher J

    2016-01-01

    Special Operations Forces (SOF) medical personnel function worldwide in environments where endemic anthrax (caused by Bacillus anthracis infection) may present in one of three forms: cutaneous, pulmonary, or gastrointestinal. This report presents a rare periocular anthrax case from Haiti to emphasize the need for heightened diagnostic suspicion of unusual lesions likely to be encountered in SOF theaters. PMID:27450596

  10. Defense against toxin weapons

    SciTech Connect

    Franz, D.R.

    1994-01-01

    The purpose of this manual is to provide basic information on biological toxins to military leaders and health-care providers at all levels to help them make informed decisions on protecting their troops from toxins. Much of the information contained herein will also be of interest to individuals charged with countering domestic and international terrorism. We typically fear what we do not understand.

  11. Preformed bacterial toxins.

    PubMed

    Crane, J K

    1999-09-01

    Food poisoning syndromes caused by four different bacteria are described. For all types, food kept at a permissive temperature allows growth of the vegetative forms of the bacteria and production of a toxin or toxins. The key features of these syndromes, as well as possible new trends of concern, are summarized in Table 1. PMID:10549427

  12. Toxins from Bacteria

    PubMed Central

    Henkel, James S.; Baldwin, Michael R.; Barbieri, Joseph T.

    2010-01-01

    Bacterial toxins damage the host at the site of bacterial infection or distanced from the site of infections. Bacterial toxins can be single proteins or organized as oligomeric protein complexes and are organized with distinct AB structure-function properties. The A domain encodes a catalytic activity; ADP-ribosylation of host proteins is the earliest post-translational modification determine to be performed by bacterial toxin, and now include glucosylation and proteolysis among other s. Bacterial toxins also catalyze the non-covalent modification of host protein function or can modify host cell properties through direct protein-protein interactions. The B domain includes two functional domains: a receptor-binding domain, which defines the tropism of a toxin for a cell and a translocation domain that delivers A domain across a lipid bilayer, either on the plasma membrane or the endosome. Bacterial toxins are often characterized based upon the section mechanism that delivers the toxin out of the bacterium, termed type I–VII. This review will overview the major families of bacterial toxins and will also describe the specific structure-function properties of the botulinum neurotoxins. PMID:20358680

  13. [Neurogenic pulmonary edema. Report of 2 cases].

    PubMed

    Dragosavac, D; Falcão, A L; Araújo, S; Terzi, R G

    1997-06-01

    Neurogenic pulmonary edema is a rare and serious complication in patients with head injury. It also may develop after a variety of cerebral insults such as subarachnoid hemorrhage, brain tumors and after epileptic seizures. Thirty six patients with severe head injury and four patients with cerebrovascular insults treated in Intensive Care Unit of HC-UNICAMP from January to September 1995 were evaluated. In this period there were two patients with neurogenic pulmonary edema, one with head injury and other with intracerebral hemorrhage. Diagnosis was made by rapid onset of pulmonary edema, severe hypoxemia, decrease of pulmonary complacence and diffuse pulmonary infiltrations, without previous history of tracheal aspiration or any other risk factor for development of adult respiratory distress syndrome. In the first case, with severe head trauma, neurogenic pulmonary edema was diagnosed at admission one hour after trauma, associated with severe systemic inflammatory reaction, and good outcome in three days. The second case, with hemorrhagic vascular insult, developed neurogenic pulmonary edema the fourth day after drainage of intracerebral hematoma and died. PMID:9629392

  14. Mechanisms of Astrocyte-Mediated Cerebral Edema

    PubMed Central

    Stokum, Jesse A.; Kurland, David B.; Gerzanich, Volodymyr; Simard, J. Marc

    2014-01-01

    Cerebral edema formation stems from disruption of blood brain barrier (BBB) integrity and occurs after injury to the CNS. Due to the restrictive skull, relatively small increases in brain volume can translate into impaired tissue perfusion and brain herniation. In excess, cerebral edema can be gravely harmful. Astrocytes are key participants in cerebral edema by virtue of their relationship with the cerebral vasculature, their unique compliment of solute and water transport proteins, and their general role in brain volume homeostasis. Following the discovery of aquaporins, passive conduits of water flow, aquaporin 4 (AQP4) was identified as the predominant astrocyte water channel. Normally, AQP4 is highly enriched at perivascular endfeet, the outermost layer of the BBB, whereas after injury, AQP4 expression disseminates to the entire astrocytic plasmalemma, a phenomenon termed dysregulation. Arguably, the most important role of AQP4 is to rapidly neutralize osmotic gradients generated by ionic transporters. In pathological conditions, AQP4 is believed to be intimately involved in the formation and clearance of cerebral edema. In this review, we discuss aquaporin function and localization in the BBB during health and injury, and we examine post-injury ionic events that modulate AQP4- dependent edema formation. PMID:24996934

  15. Proteinaceous toxins from three species of scorpaeniform fish (lionfish Pterois lunulata, devil stinger Inimicus japonicus and waspfish Hypodytes rubripinnis): close similarity in properties and primary structures to stonefish toxins.

    PubMed

    Kiriake, Aya; Suzuki, Yasuko; Nagashima, Yuji; Shiomi, Kazuo

    2013-08-01

    The crude toxins from three species of venomous fish (lionfish Pterois lunulata, devil stinger Inimicus japonicus and waspfish Hypodytes rubripinnis) belonging to the order Scorpaeniformes exhibited mouse-lethal, hemolytic, edema-forming and nociceptive activities. In view of the antigenic cross-reactivity with the stonefish toxins, the primary structures of the stonefish toxin-like toxins from the three scorpaeniform fish were determined by cDNA cloning using primers designed from the highly conserved sequences of the stonefish toxins. Based on the data obtained in gel filtration, immunoblotting and cDNA cloning, each toxin was judged to be a 160 kDa heterodimer composed of 80 kDa α- and β-subunits. The three scorpaeniform fish toxins contain a B30.2/SPRY domain (∼200 amino acid residues) in the C-terminal region of each subunit, as reported for the toxins from two species of lionfish and two species of stonefish. With respect to the amino acid sequence similarity, the scorpaeniform fish toxins are divided into the following two groups: toxins from three species of lionfish and those from devil stinger, two species of stonefish and waspfish. The phylogenetic tree generated also clearly supports the classification of the toxins. PMID:23665450

  16. Development of a differential scanning fluorimetry based high throughput screening assay for the discovery of affinity binders against an anthrax protein.

    PubMed

    Sorrell, Fiona J; Greenwood, Gemma K; Birchall, Kristian; Chen, Beining

    2010-09-01

    The anthrax protein protective antigen (PA) is responsible for cell-surface recognition and aids the delivery of the toxic anthrax enzymes into host cells. By targeting PA and preventing it from binding to host cells, it is hoped that the delivery of toxins into the cell will be inhibited. The current assay reported for PA is a low throughput functional assay. Here, the high throughput screening method using differential scanning fluorimetry (DSF) was developed and optimized to screen a number of libraries from various sources including a selection of FDA-approved drugs as well as hits selected by a virtual screening campaign. DSF is a rapid technique that uses fluorescence to monitor the thermal unfolding of proteins using a standard QPCR instrument. A positive shift in the calculated melting temperature (Tm), of the protein in the presence of a compound, relative to the Tm of the unbound protein, indicates that stabilization of the protein by ligand binding may have occurred. Optimization of the melting assay showed SYPRO Orange to be an ideal dye as a marker and lead to the reduction of DMSO concentration to <1% (v/v) in the final assay. The final assay volume was minimized to 25 L with 5 g protein per well of 96-well plate. In addition, a buffer, salt and additive screen lead to the selection of 10 mM HEPES-NaOH pH 7.5, 100 mM NaCl as the assay buffer. This method has been shown here to be useful as a primary method for the detection of small-molecule PA ligands, giving a hit rate of approximately 7%. These ligands can then be studied further using PA functional assays to confirm their biological activities before being selected as lead compounds for the treatment of anthrax. PMID:20376913

  17. Marked enhancement of the immune response to BioThrax® (Anthrax Vaccine Adsorbed) by the TLR9 agonist CPG 7909 in healthy volunteers.

    PubMed

    Rynkiewicz, Dianna; Rathkopf, Melinda; Sim, Iain; Waytes, A Thomas; Hopkins, Robert J; Giri, Lallan; DeMuria, Deborah; Ransom, Janet; Quinn, James; Nabors, Gary S; Nielsen, Carl J

    2011-08-26

    Immunization with BioThrax(®) (Anthrax Vaccine Adsorbed) is a safe and effective means of preventing anthrax. Animal studies have demonstrated that the addition of CpG DNA adjuvants to BioThrax can markedly increase the immunogenicity of the vaccine, increasing both serum anti-protective antigen (PA) antibody and anthrax toxin-neutralizing antibody (TNA) concentrations. The immune response to CpG-adjuvanted BioThrax in animals was not only stronger, but was also more rapid and led to higher levels of protection in spore challenge models. The B-class CpG DNA adjuvant CPG 7909, a 24-base synthetic, single-strand oligodeoxynucleotide, was evaluated for its safety profile and adjuvant properties in a Phase 1 clinical trial. A double-blind study was performed in which 69 healthy subjects, age 18-45 years, were randomized to receive three doses of either: (1) BioThrax alone, (2) 1 mg of CPG 7909 alone or (3) BioThrax plus 1 mg of CPG 7909, all given intramuscularly on study days 0, 14 and 28. Subjects were monitored for IgG to PA by ELISA and for TNA titers through study day 56 and for safety through month 6. CPG 7909 increased the antibody response by 6-8-fold at peak, and accelerated the response by 3 weeks compared to the response seen in subjects vaccinated with BioThrax alone. No serious adverse events related to study agents were reported, and the combination was considered to be reasonably well tolerated. The marked acceleration and enhancement of the immune response seen by combining BioThrax and CPG 7909 offers the potential to shorten the course of immunization and reduce the time to protection, and may be particularly useful in the setting of post-exposure prophylaxis. PMID:21624418

  18. Protection of rhesus macaques against inhalational anthrax with a Bacillus anthracis capsule conjugate vaccine.

    PubMed

    Chabot, Donald J; Ribot, Wilson J; Joyce, Joseph; Cook, James; Hepler, Robert; Nahas, Debbie; Chua, Jennifer; Friedlander, Arthur M

    2016-07-25

    The efficacy of currently licensed anthrax vaccines is largely attributable to a single Bacillus anthracis immunogen, protective antigen. To broaden protection against possible strains resistant to protective antigen-based vaccines, we previously developed a vaccine in which the anthrax polyglutamic acid capsule was covalently conjugated to the outer membrane protein complex of Neisseria meningitidis serotype B and demonstrated that two doses of 2.5μg of this vaccine conferred partial protection of rhesus macaques against inhalational anthrax . Here, we demonstrate complete protection of rhesus macaques against inhalational anthrax with a higher 50μg dose of the same capsule conjugate vaccine. These results indicate that B. anthracis capsule is a highly effective vaccine component that should be considered for incorporation in future generation anthrax vaccines. PMID:27329184

  19. Mucosal priming of newborn mice with S. Typhi Ty21a expressing anthrax protective antigen (PA) followed by parenteral PA-boost induces B and T cell-mediated immunity that protects against infection bypassing maternal antibodies.

    PubMed

    Ramirez, Karina; Ditamo, Yanina; Galen, James E; Baillie, Les W J; Pasetti, Marcela F

    2010-08-23

    The currently licensed anthrax vaccine has several limitations and its efficacy has been proven only in adults. Effective immunization of newborns and infants requires adequate stimulation of their immune system, which is competent but not fully activated. We explored the use of the licensed live attenuated S. Typhi vaccine strain Ty21a expressing Bacillus anthracis protective antigen [Ty21a(PA)] followed PA-alum as a strategy for immunizing the pediatric population. Newborn mice primed with a single dose of Ty21a(PA) exhibited high frequencies of mucosal IgA-secreting B cells and IFN-gamma-secreting T cells during the neonatal period, none of which was detected in newborns immunized with a single dose of PA-alum. Priming with Ty21a(PA) followed by PA-boost resulted in high levels of PA-specific IgG, toxin neutralizing and opsonophagocytic antibodies and increased frequency of bone marrow IgG plasma cells and memory B cells compared with repeated immunization with PA-alum alone. Robust B and T cell responses developed even in the presence of maternal antibodies. The prime-boost protected against systemic and respiratory infection. Mucosal priming with a safe and effective S. Typhi-based anthrax vaccine followed by PA-boost could serve as a practical and effective prophylactic approach to prevent anthrax early in life. PMID:20619377

  20. Diabetic macular edema: New promising therapies

    PubMed Central

    Shamsi, Hanan N Al; Masaud, Jluwi S; Ghazi, Nicola G

    2013-01-01

    The treatment of diabetic macular edema is rapidly evolving. The era of laser therapy is being quickly replaced by an era of pharmacotherapy. Several pharmacotherapies have been recently developed for the treatment of retinal vascular diseases such as diabetic macular edema. Several intravitreal injections or sustained delivery devices have undergone phase 3 testing while others are currently being evaluated. The results of clinical trials have shown the superiority of some of these agents to laser therapy. However, with the availability of several of these newer agents, it may be difficult to individualize treatment options especially those patients respond differently to various therapies. As such, more effort is still needed in order to determine the best treatment regimen for a given patient. In this article, we briefly summarize the major new therapeutic additions for the treatment of diabetic macular edema and allude to some future promising therapies. PMID:24379924

  1. Novel imaging techniques for diabetic macular edema.

    PubMed

    Lobo, C; Bernardes, R; Faria de Abreu, J R; Cunha-Vaz, J G

    1999-01-01

    Retinal edema should be defined as any increase of water of the retinal tissue resulting in an increase in its volume. It may be of cytotoxic or vasogenic origin. Development of vasogenic macular edema is dependent on a series of factors such as blood pressure, blood-retinal barrier permeability, retinal cell damage, retinal tissue osmotic pressure and retinal tissue compliance. Objective measurements of retinal thickness are now possible using the Retinal Thickness Analyser. Localised measurements of blood-retinal barrier permeability may also be obtained using the Retinal Leakage Analyser, a modified confocal scanning laser fluorometer, while obtaining simultaneously angiographic images of the choroid and retina. These new imaging techniques show that cytotoxic and vasogenic retinal edema may occur independently in the early stages of diabetic retinopathy. These findings offer new perspectives for designing novel therapeutic strategies. PMID:10896349

  2. Acute pulmonary edema caused by quinine.

    PubMed

    Everts, Richard J; Hayhurst, Michael D; Nona, Basim P

    2004-09-01

    A 57-year-old man who had been intermittently taking one 300-mg tablet of quinine sulfate orally for leg cramps experienced transient acute pulmonary edema and hypotension 30-40 minutes after ingestion on two consecutive occasions. He was not taking any concomitant drugs, and there was no alternative explanation for either event. Serial troponin T tests and electrocardiograms, obtained on admission to the hospital, followed by an outpatient echocardiogram and a coronary angiogram, were essentially normal. We compared this case with one previously published and nine previously unpublished reports of quinine-associated pulmonary edema and conclude that some cases of pulmonary edema or adult respiratory distress syndrome in patients with malaria may be caused by an adverse reaction to quinine. Although infrequent, clinicians should be aware of this potentially serious and costly adverse reaction. PMID:15460183

  3. Understanding malarial toxins.

    PubMed

    Starkl Renar, Katarina; Iskra, Jernej; Križaj, Igor

    2016-09-01

    Recognized since antiquity, malaria is one of the most infamous and widespread infectious diseases in humans and, although the death rate during the last century has been diminishing, it still accounts for more than a half million deaths annually. It is caused by the Plasmodium parasite and typical symptoms include fever, shivering, headache, diaphoresis and nausea, all resulting from an excessive inflammatory response induced by malarial toxins released into the victim's bloodstream. These toxins are hemozoin and glycosylphosphatidylinositols. The former is the final product of the parasite's detoxification of haeme, a by-product of haemoglobin catabolism, while the latter anchor proteins to the Plasmodium cell surface or occur as free molecules. Currently, only two groups of antimalarial toxin drugs exist on the market, quinolines and artemisinins. As we describe, they both target biosynthesis of hemozoin. Other substances, currently in various phases of clinical trials, are directed towards biosynthesis of glycosylphosphatidylinositol, formation of hemozoin, or attenuation of the inflammatory response of the patient. Among the innovative approaches to alleviating the effects of malarial toxins, is the development of antimalarial toxin vaccines. In this review the most important lessons learned from the use of treatments directed against the action of malarial toxins in antimalarial therapy are emphasized and the most relevant and promising directions for future research in obtaining novel antimalarial agents acting on malarial toxins are discussed. PMID:27353131

  4. Mechanisms of Ricin Toxin Neutralization Revealed through Engineered Homodimeric and Heterodimeric Camelid Antibodies.

    PubMed

    Herrera, Cristina; Tremblay, Jacqueline M; Shoemaker, Charles B; Mantis, Nicholas J

    2015-11-13

    Novel antibody constructs consisting of two or more different camelid heavy-chain only antibodies (VHHs) joined via peptide linkers have proven to have potent toxin-neutralizing activity in vivo against Shiga, botulinum, Clostridium difficile, anthrax, and ricin toxins. However, the mechanisms by which these so-called bispecific VHH heterodimers promote toxin neutralization remain poorly understood. In the current study we produced a new collection of ricin-specific VHH heterodimers, as well as VHH homodimers, and characterized them for their ability neutralize ricin in vitro and in vivo. We demonstrate that the VHH heterodimers, but not homodimers were able to completely protect mice against ricin challenge, even though the two classes of antibodies (heterodimers and homodimers) had virtually identical affinities for ricin holotoxin and similar IC50 values in a Vero cell cytotoxicity assay. The VHH heterodimers did differ from the homodimers in their ability to promote toxin aggregation in solution, as revealed through analytical ultracentrifugation. Moreover, the VHH heterodimers that were most effective at promoting ricin aggregation in solution were also the most effective at blocking ricin attachment to cell surfaces. Collectively, these data suggest that heterodimeric VHH-based neutralizing agents may function through the formation of antibody-toxin complexes that are impaired in their ability to access host cell receptors. PMID:26396190

  5. A recombinant Bacillus anthracis strain producing the Clostridium perfringens Ib component induces protection against iota toxins.

    PubMed Central

    Sirard, J C; Weber, M; Duflot, E; Popoff, M R; Mock, M

    1997-01-01

    The Bacillus anthracis toxinogenic Sterne strain is currently used as a live veterinary vaccine against anthrax. The capacity of a toxin-deficient derivative strain to produce a heterologous antigen by using the strong inducible promoter of the B. anthracis pag gene was investigated. The expression of the foreign gene ibp, encoding the Ib component of iota toxin from Clostridium perfringens, was analyzed. A pag-ibp fusion was introduced by allelic exchange into a toxin-deficient Sterne strain, thereby replacing the wild-type pag gene. This recombinant strain, called BAIB, was stable and secreted large quantities of Ib protein in induced culture conditions. Mice given injections of live BAIB spores developed an antibody response specific to the Ib protein. The pag-ibp fusion was therefore functional both in vitro and in vivo. Moreover, the immunized animals were protected against a challenge with C. perfringens iota toxin or with the homologous Clostridium spiroforme toxin. The protective immunity was mediated by neutralizing antibodies. In conclusion, B. anthracis is promising for the development of live veterinary vaccines. PMID:9169728

  6. Bacterial toxins: friends or foes?

    PubMed Central

    Schmitt, C. K.; Meysick, K. C.; O'Brien, A. D.

    1999-01-01

    Many emerging and reemerging bacterial pathogens synthesize toxins that serve as primary virulence factors. We highlight seven bacterial toxins produced by well-established or newly emergent pathogenic microbes. These toxins, which affect eukaryotic cells by a variety of means, include Staphylococcus aureus alpha-toxin, Shiga toxin, cytotoxic necrotizing factor type 1, Escherichia coli heat-stable toxin, botulinum and tetanus neurotoxins, and S. aureus toxic-shock syndrome toxin. For each, we discuss the information available on its synthesis and structure, mode of action, and contribution to virulence. We also review the role certain toxins have played in unraveling signal pathways in eukaryotic cells and summarize the beneficial uses of toxins and toxoids. Our intent is to illustrate the importance of the analysis of bacterial toxins to both basic and applied sciences. PMID:10221874

  7. Swab protocol for rapid laboratory diagnosis of cutaneous anthrax.

    PubMed

    Dauphin, Leslie A; Marston, Chung K; Bhullar, Vinod; Baker, Daniel; Rahman, Mahmudur; Hossain, M Jahangir; Chakraborty, Apurba; Khan, Salah Uddin; Hoffmaster, Alex R

    2012-12-01

    The clinical laboratory diagnosis of cutaneous anthrax is generally established by conventional microbiological methods, such as culture and directly straining smears of clinical specimens. However, these methods rely on recovery of viable Bacillus anthracis cells from swabs of cutaneous lesions and often yield negative results. This study developed a rapid protocol for detection of B. anthracis on clinical swabs. Three types of swabs, flocked-nylon, rayon, and polyester, were evaluated by 3 extraction methods, the swab extraction tube system (SETS), sonication, and vortex. Swabs were spiked with virulent B. anthracis cells, and the methods were compared for their efficiency over time by culture and real-time PCR. Viability testing indicated that the SETS yielded greater recovery of B. anthracis from 1-day-old swabs; however, reduced viability was consistent for the 3 extraction methods after 7 days and nonviability was consistent by 28 days. Real-time PCR analysis showed that the PCR amplification was not impacted by time for any swab extraction method and that the SETS method provided the lowest limit of detection. When evaluated using lesion swabs from cutaneous anthrax outbreaks, the SETS yielded culture-negative, PCR-positive results. This study demonstrated that swab extraction methods differ in their efficiency of recovery of viable B. anthracis cells. Furthermore, the results indicated that culture is not reliable for isolation of B. anthracis from swabs at ≥ 7 days. Thus, we recommend the use of the SETS method with subsequent testing by culture and real-time PCR for diagnosis of cutaneous anthrax from clinical swabs of cutaneous lesions. PMID:23035192

  8. INTRAVITREAL CORTICOSTEROIDS IN DIABETIC MACULAR EDEMA

    PubMed Central

    Bailey, Clare; Loewenstein, Anat; Massin, Pascale

    2015-01-01

    Purpose: To review the relationship between kinetics, efficacy, and safety of several corticosteroid formulations for the treatment of diabetic macular edema. Methods: Reports of corticosteroid use for the treatment of diabetic macular edema were identified by a literature search, which focused on the pharmacokinetics, efficacy, and safety of these agents in preclinical animal models and clinical trials. Results: Available corticosteroids for diabetic macular edema treatment include intravitreal triamcinolone acetonide, dexamethasone, and fluocinolone acetonide. Because of differences in solubility and bioavailability, various delivery mechanisms are used. Bioerodible delivery systems achieve higher maximum concentrations than nonbioerodible formulations. There is a relationship between visual gains and drug persistence in the intravitreal compartment. Safety effects were more complex; level of intravitreal triamcinolone acetonide exposure is related to development of elevated intraocular pressure and cataract; this does not seem to be the case for dexamethasone, where two different doses showed similar mean intraocular pressure and incidence of cataract surgery. With fluocinolone acetonide, rates of intraocular pressure elevations requiring surgery seem to be dose related; rates of cataract extraction were similar regardless of dose. Conclusion: Available corticosteroids for diabetic macular edema exhibit different pharmacokinetic profiles that impact efficacy and adverse events and should be taken into account when developing individualized treatment plans. PMID:26352555

  9. An uncommon cause of acute pulmonary edema.

    PubMed

    Nepal, Santosh; Giri, Smith; Bhusal, Mohan; Siwakoti, Krishmita; Pathak, Ranjan

    2016-09-01

    Acute cardiogenic pulmonary edema secondary to catecholamine-induced cardiomyopathy is a very uncommon and fatal initial presentation of pheochromocytoma. However, with early clinical suspicion and aggressive management, the condition is reversible. This case report describes a patient who presented with hypertension, dyspnea, and cough with bloody streaks, and who recovered within 48 hours after appropriate treatment. PMID:27575897

  10. Current status in diabetic macular edema treatments.

    PubMed

    Romero-Aroca, Pedro

    2013-10-15

    Diabetes is a serious chronic condition, which increase the risk of cardiovascular diseases, kidney failure and nerve damage leading to amputation. Furthermore the ocular complications include diabetic macular edema, is the leading cause of blindness among adults in the industrialized countries. Today, blindness from diabetic macular edema is largely preventable with timely detection and appropriate interventional therapy. The treatment should include an optimized control of glycemia, arterial tension, lipids and renal status. The photocoagulation laser is currently restricted to focal macular edema in some countries, but due the high cost of intravitreal drugs, the use of laser treatment for focal and diffuse diabetic macular edema (DME), can be valid as gold standard in many countries. The intravitreal anti vascular endothelial growth factor drugs (ranibizumab and bevacizumab), are indicated in the treatment of all types of DME, but the correct protocol for administration should be defined for the different Retina Scientific Societies. The corticosteroids for diffuse DME, has a place in pseudophakic patients, but its complications restricted the use of these drugs for some patients. Finally the intravitreal interface plays an important role and its exploration is mandatory in all DME patients. PMID:24147200

  11. CDC Report on the Potential Exposure to Anthrax.

    PubMed

    2014-06-01

    The Centers for Disease Control and Prevention (CDC) conducted an internal review of an incident that involved an unintentional release of potentially viable anthrax within its Roybal Campus, in Atlanta, Georgia. On June 5, 2014, a laboratory scientist in the Bioterrorism Rapid Response and Advanced Technology (BRRAT) laboratory prepared extracts from a panel of eight bacterial select agents, including Bacillus anthracis (B. anthracis), under biosafety level (BSL) 3 containment conditions. These samples were being prepared for analysis using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry, a technology that can be used for rapid bacterial species identification. PMID:26418856

  12. Decontamination of Anthrax spores in critical infrastructure and critical assets.

    SciTech Connect

    Boucher, Raymond M.; Crown, Kevin K.; Tucker, Mark David; Hankins, Matthew Granholm

    2010-05-01

    Decontamination of anthrax spores in critical infrastructure (e.g., subway systems, major airports) and critical assets (e.g., the interior of aircraft) can be challenging because effective decontaminants can damage materials. Current decontamination methods require the use of highly toxic and/or highly corrosive chemical solutions because bacterial spores are very difficult to kill. Bacterial spores such as Bacillus anthracis, the infectious agent of anthrax, are one of the most resistant forms of life and are several orders of magnitude more difficult to kill than their associated vegetative cells. Remediation of facilities and other spaces (e.g., subways, airports, and the interior of aircraft) contaminated with anthrax spores currently requires highly toxic and corrosive chemicals such as chlorine dioxide gas, vapor- phase hydrogen peroxide, or high-strength bleach, typically requiring complex deployment methods. We have developed a non-toxic, non-corrosive decontamination method to kill highly resistant bacterial spores in critical infrastructure and critical assets. A chemical solution that triggers the germination process in bacterial spores and causes those spores to rapidly and completely change to much less-resistant vegetative cells that can be easily killed. Vegetative cells are then exposed to mild chemicals (e.g., low concentrations of hydrogen peroxide, quaternary ammonium compounds, alcohols, aldehydes, etc.) or natural elements (e.g., heat, humidity, ultraviolet light, etc.) for complete and rapid kill. Our process employs a novel germination solution consisting of low-cost, non-toxic and non-corrosive chemicals. We are testing both direct surface application and aerosol delivery of the solutions. A key Homeland Security need is to develop the capability to rapidly recover from an attack utilizing biological warfare agents. This project will provide the capability to rapidly and safely decontaminate critical facilities and assets to return them to

  13. Keeping the Air Clean and Safe: An Anthrax Smoke Detector

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Scientists at work in the Planetary Protection division at NASA s Jet Propulsion Laboratory (JPL) sterilize everything before blasting it to the Red Planet. They take great pains to ensure that all spacecraft are void of bacterial life, especially the microscopic bacteria that can live hundreds of years in their spore states. No one is quite sure what Earthly germs would do on Mars, but scientists agree that it is safest to keep the Martian terrain as undisturbed as possible. Errant Earth germs would also render useless the instruments placed on exploration rovers to look for signs of life, as the life that they registered would be life that came with them from Earth. A team at JPL, headed by Dr. Adrian Ponce, developed a bacterial spore-detection system that uses a simple and robust chemical reaction that visually alerts Planetary Protection crews. It is a simple air filter that traps micron-sized bacterial spores and then submits them to the chemical reaction. When the solution is then viewed under an ultraviolet light, the mixture will glow green if it is contaminated by bacteria. Scientists can then return to the scrubbing and cleaning stages of the sterilization process to remove these harmful bacteria. The detection system is the space-bound equivalent of having your hands checked for cleanliness before being allowed to the table; and although intended to keep terrestrial germs from space, this technology has awesome applications here on Mother Earth. The bacterial spore-detection unit can recognize anthrax and other harmful, spore-forming bacteria and alert people of the impending danger. As evidenced in the anthrax mailings of fall 2001 in the United States, the first sign of anthrax exposure was when people experienced flu-like symptoms, which unfortunately, can take as much as a week to develop after contamination. Anthrax cost 5 people their lives and infected 19 others; and the threat of bioterrorism became a routine concern, with new threats popping up

  14. Anthrax attack at the United States Capitol. Front line thoughts.

    PubMed

    Anderson, Andrea; Eisold, John F

    2002-04-01

    One great fear was realized on October 15, 2001 when United States citizens witnessed firsthand the unprecedented release of anthrax into a community. Although the office of the Attending Physician to Congress had been preparing for such an unthinkable act, lessons were learned as the events unfolded. The following is a summary of the findings: Preparation, planning, and frequent review of bioterrorism response procedures are essential. Effective communication remains the key to successful team performance. Briefings conducted daily and on an as needed basis shape the progress and performance of the team members. Electronic mail may not necessarily be the most effective way to disseminate critical information because not everyone can access the Internet outside of the work environment. Setting up a call center for answering client's questions is crucial. Clients potentially exposed to anthrax should be evacuated from the immediate area. Testing is not indicated for everyone, only those in the immediate areas. Allow health care personnel to decide whom should be tested. Such health care decisions must not be made based on anxiety or expediency. A data collection template should be set up in advance. This template should include, at least, the following: name, date of birth, social security number, the physical location of where the client might have been exposed, antibiotics administered and dosage, test results, and home and work phone number. This should be networked so a group can access and update data in real time. If the occupational health clinic has its own pharmacy, have a pill counter available to help with antibiotic distribution. The team should meet several times daily to ensure dissemination of a reliable and consistent message to the clients. Team members should be prepared to review the medical aspects of anthrax with clients on a frequent basis. A website with updated information might prove helpful for those with Internet access. This experience

  15. Assessment and management of cerebral edema and intracranial hypertension in acute liver failure.

    PubMed

    Mohsenin, Vahid

    2013-10-01

    Acute liver failure is uncommon but not a rare complication of liver injury. It can happen after ingestion of acetaminophen and exposure to toxins and hepatitis viruses. The defining clinical symptoms are coagulopathy and encephalopathy occurring within days or weeks of the primary insult in patients without preexisting liver injury. Acute liver failure is often complicated by multiorgan failure and sepsis. The most life-threatening complications are sepsis, multiorgan failure, and brain edema. The clinical signs of increased intracranial pressure (ICP) are nonspecific except for neurologic deficits in impending brain stem herniation. Computed tomography of the brain is not sensitive enough in gauging intracranial hypertension or ruling out brain edema. Intracranial pressure monitoring, transcranial Doppler, and jugular venous oximetry provide valuable information for monitoring ICP and guiding therapeutic measures in patients with encephalopathy grade III or IV. Osmotic therapy using hypertonic saline and mannitol, therapeutic hypothermia, and propofol sedation are shown to improve ICPs and stabilize the patient for liver transplantation. In this article, diagnosis and management of hepatic encephalopathy and cerebral edema in patients with acute liver failure are reviewed. PMID:23683564

  16. A Simple Luminescent Adenylate-Cyclase Functional Assay for Evaluation of Bacillus anthracis Edema Factor Activity

    PubMed Central

    Israeli, Ma’ayan; Rotem, Shahar; Elia, Uri; Bar-Haim, Erez; Cohen, Ofer; Chitlaru, Theodor

    2016-01-01

    Edema Factor (EF), the toxic sub-unit of the Bacillus anthracis Edema Toxin (ET) is a calmodulin-dependent adenylate cyclase whose detrimental activity in the infected host results in severe edema. EF is therefore a major virulence factor of B. anthracis. We describe a simple, rapid and reliable functional adenylate-cyclase assay based on inhibition of a luciferase-mediated luminescence reaction. The assay exploits the efficient adenylate cyclase-mediated depletion of adenosine tri-phosphate (ATP), and the strict dependence on ATP of the light-emitting luciferase-catalyzed luciferin-conversion to oxyluciferin, which can be easily visualized. The assay exhibits a robust EF-dose response decrease in luminescence, which may be specifically reverted by anti-EF antibodies. The application of the assay is exemplified in: (a) determining the presence of EF in B. anthracis cultures, or its absence in cultures of EF-defective strains; (b) evaluating the anti-EF humoral response in experimental animals infected/vaccinated with B. anthracis; and (c) rapid discrimination between EF producing and non-producing bacterial colonies. Furthermore, the assay may be amenable with high-throughput screening for EF inhibitory molecules. PMID:27548219

  17. A Simple Luminescent Adenylate-Cyclase Functional Assay for Evaluation of Bacillus anthracis Edema Factor Activity.

    PubMed

    Israeli, Ma'ayan; Rotem, Shahar; Elia, Uri; Bar-Haim, Erez; Cohen, Ofer; Chitlaru, Theodor

    2016-01-01

    Edema Factor (EF), the toxic sub-unit of the Bacillus anthracis Edema Toxin (ET) is a calmodulin-dependent adenylate cyclase whose detrimental activity in the infected host results in severe edema. EF is therefore a major virulence factor of B. anthracis. We describe a simple, rapid and reliable functional adenylate-cyclase assay based on inhibition of a luciferase-mediated luminescence reaction. The assay exploits the efficient adenylate cyclase-mediated depletion of adenosine tri-phosphate (ATP), and the strict dependence on ATP of the light-emitting luciferase-catalyzed luciferin-conversion to oxyluciferin, which can be easily visualized. The assay exhibits a robust EF-dose response decrease in luminescence, which may be specifically reverted by anti-EF antibodies. The application of the assay is exemplified in: (a) determining the presence of EF in B. anthracis cultures, or its absence in cultures of EF-defective strains; (b) evaluating the anti-EF humoral response in experimental animals infected/vaccinated with B. anthracis; and (c) rapid discrimination between EF producing and non-producing bacterial colonies. Furthermore, the assay may be amenable with high-throughput screening for EF inhibitory molecules. PMID:27548219

  18. The effect of seasonal variation on anthrax epidemiology in the upper Zambezi floodplain of western Zambia

    PubMed Central

    Banda, Fredrick; Siamudaala, Victor Mukulule; Munyeme, Musso; Kasanga, Christopher Jacob; Hamududu, Byman

    2012-01-01

    Anthrax has become endemic throughout the upper Zambezi floodplain located in the Western Province of Zambia over the recent years. To date, no comprehensive study has been carried out to determine whether recurrence of anthrax outbreaks may be linked to differences in precipitation and human activities. Retrospective data for the period 1999 to 2007 showed that a total of 1,216 bovine cases of anthrax were reported. During the same period, 1,790 human anthrax cases and a corresponding case fatality rate of 4.63% (83/1,790) was documented in the upper Zambezi floodplain. Occurrence of human cases was highly correlated with cattle outbreaks (r = 0.94, p < 0.001). Differences in precipitation were significantly associated with the occurrence of anthrax outbreaks (χ2 = 4.75, p < 0.03), indicating that the likelihood of outbreaks occurring was higher during the dry months when human occupancy of the floodplain was greater compared to the flooding months when people and livestock moved out of this region. Human dependency on the floodplain was shown to significantly influence the epidemiology of anthrax in the upper Zambezi floodplain of western Zambia. Methods for mitigating anthrax outbreaks by disrupting the cycle of transmission are herein highlighted. PMID:23000586

  19. Predicting Disease Risk, Identifying Stakeholders, and Informing Control Strategies: A Case Study of Anthrax in Montana.

    PubMed

    Morris, Lillian R; Blackburn, Jason K

    2016-06-01

    Infectious diseases that affect wildlife and livestock are challenging to manage and can lead to large-scale die-offs, economic losses, and threats to human health. The management of infectious diseases in wildlife and livestock is made easier with knowledge of disease risk across space and identifying stakeholders associated with high-risk landscapes. This study focuses on anthrax, caused by the bacterium Bacillus anthracis, risk to wildlife and livestock in Montana. There is a history of anthrax in Montana, but the spatial extent of disease risk and subsequent wildlife species at risk are not known. Our objective was to predict the potential geographic distribution of anthrax risk across Montana, identify wildlife species at risk and their distributions, and define stakeholders. We used an ecological niche model to predict the potential distribution of anthrax risk. We overlaid susceptible wildlife species distributions and land ownership delineations on our risk map. We found that there was an extensive region across Montana predicted as potential anthrax risk. These potentially risky landscapes overlapped the ranges of all 6 ungulate species considered in the analysis and livestock grazing allotments, and this overlap was on public and private land for all species. Our findings suggest that there is the potential for a multi-species anthrax outbreak on multiple landscapes across Montana. Our potential anthrax risk map can be used to prioritize landscapes for surveillance and for implementing livestock vaccination programs. PMID:27169560

  20. Phylogenetic Characteristics of Anthrax Outbreaks in Liaoning Province, China, 2001-2015.

    PubMed

    Mao, Lingling; Zhang, Enmin; Wang, Zijiang; Li, Yan; Zhou, Hang; Liu, Xuesheng; Zhang, Huijuan; Cai, Hong; Liang, Xudong; Sun, Yingwei; Zhang, Zhikai; Li, Wei; Yao, Wenqing; Wei, Jianchun

    2016-01-01

    Anthrax is a continuous threat in China, especially in rural regions. In July 2015, an anthrax outbreak occurred in Xifeng County, Liaoning Province. A total of 10 cutaneous anthrax cases were reported, with 210 people under medical observation. In this study, the general characteristics of human anthrax outbreak occurred in Liaoning Province were described, and all cases were caused by butchering and contacting sick animal. Meanwhile, the phylogenetic relationship between outbreak-related isolates/samples of the year 2015 and previous Bacillus anthracis strains was analyzed by means of canonical single nucleotide polymorphisms (canSNP), multiple-locus variable-number tandem repeat analysis (MLVA) with 15 markers and single-nucleotide repeats (SNR) analysis. There are two canSNP subgroups found in Liaoning, A.Br.001/002 and A.Br.Ames, and a total of six MLVA 15 genotypes and five SNR genotypes were observed. The strain collected from anthrax outbreak in Xifeng County in 2015 was classified as A.Br.001/002 subgroup and identified as MLVA15-29 genotype, with same SNR profile (CL10: 17, CL12: 15, CL33: 29, and CL35: 13). So we conclude that the same clone of B.anthracis caused the anthrax outbreak in Xifeng County in 2015, and this clone is different to previous isolates. Strengthening public health education in China is one of the most important measures to prevent and control anthrax. PMID:27299730

  1. Phylogenetic Characteristics of Anthrax Outbreaks in Liaoning Province, China, 2001-2015

    PubMed Central

    Wang, Zijiang; Li, Yan; Zhou, Hang; Liu, Xuesheng; Zhang, Huijuan; Cai, Hong; Liang, Xudong; Sun, Yingwei; Zhang, Zhikai; Li, Wei; Yao, Wenqing; Wei, Jianchun

    2016-01-01

    Anthrax is a continuous threat in China, especially in rural regions. In July 2015, an anthrax outbreak occurred in Xifeng County, Liaoning Province. A total of 10 cutaneous anthrax cases were reported, with 210 people under medical observation. In this study, the general characteristics of human anthrax outbreak occurred in Liaoning Province were described, and all cases were caused by butchering and contacting sick animal. Meanwhile, the phylogenetic relationship between outbreak-related isolates/samples of the year 2015 and previous Bacillus anthracis strains was analyzed by means of canonical single nucleotide polymorphisms (canSNP), multiple-locus variable-number tandem repeat analysis (MLVA) with 15 markers and single-nucleotide repeats (SNR) analysis. There are two canSNP subgroups found in Liaoning, A.Br.001/002 and A.Br.Ames, and a total of six MLVA 15 genotypes and five SNR genotypes were observed. The strain collected from anthrax outbreak in Xifeng County in 2015 was classified as A.Br.001/002 subgroup and identified as MLVA15-29 genotype, with same SNR profile (CL10: 17, CL12: 15, CL33: 29, and CL35: 13). So we conclude that the same clone of B.anthracis caused the anthrax outbreak in Xifeng County in 2015, and this clone is different to previous isolates. Strengthening public health education in China is one of the most important measures to prevent and control anthrax. PMID:27299730

  2. 19F Nuclear Magnetic Resonance and Crystallographic Studies of 5-Fluorotryptophan-Labeled Anthrax Protective Antigen and Effects of the Receptor on Stability

    PubMed Central

    2015-01-01

    The anthrax protective antigen (PA) is an 83 kDa protein that is one of three protein components of the anthrax toxin, an AB toxin secreted by Bacillus anthracis. PA is capable of undergoing several structural changes, including oligomerization to either a heptameric or octameric structure called the prepore, and at acidic pH a major conformational change to form a membrane-spanning pore. To follow these structural changes at a residue-specific level, we have conducted initial studies in which we have biosynthetically incorporated 5-fluorotryptophan (5-FTrp) into PA, and we have studied the influence of 5-FTrp labeling on the structural stability of PA and on binding to the host receptor capillary morphogenesis protein 2 (CMG2) using 19F nuclear magnetic resonance (NMR). There are seven tryptophans in PA, but of the four domains in PA, only two contain tryptophans: domain 1 (Trp65, -90, -136, -206, and -226) and domain 2 (Trp346 and -477). Trp346 is of particular interest because of its proximity to the CMG2 binding interface, and because it forms part of the membrane-spanning pore. We show that the 19F resonance of Trp346 is sensitive to changes in pH, consistent with crystallographic studies, and that receptor binding significantly stabilizes Trp346 to both pH and temperature. In addition, we provide evidence that suggests that resonances from tryptophans distant from the binding interface are also stabilized by the receptor. Our studies highlight the positive impact of receptor binding on protein stability and the use of 19F NMR in gaining insight into structural changes in a high-molecular weight protein. PMID:24387629

  3. Functional analysis of neutralizing antibodies against Clostridium perfringens epsilon-toxin.

    PubMed

    McClain, Mark S; Cover, Timothy L

    2007-04-01

    The Clostridium perfringens epsilon-toxin causes a severe, often fatal illness (enterotoxemia) characterized by cardiac, pulmonary, kidney, and brain edema. In this study, we examined the activities of two neutralizing monoclonal antibodies against the C. perfringens epsilon-toxin. Both antibodies inhibited epsilon-toxin cytotoxicity towards cultured MDCK cells and inhibited the ability of the toxin to form pores in the plasma membranes of cells, as shown by staining cells with the membrane-impermeant dye 7-aminoactinomycin D. Using an antibody competition enzyme-linked immunosorbent assay (ELISA), a peptide array, and analysis of mutant toxins, we mapped the epitope recognized by one of the neutralizing monoclonal antibodies to amino acids 134 to 145. The antibody competition ELISA and analysis of mutant toxins suggest that the second neutralizing monoclonal antibody also recognizes an epitope in close proximity to this region. The region comprised of amino acids 134 to 145 overlaps an amphipathic loop corresponding to the putative membrane insertion domain of the toxin. Identifying the epitopes recognized by these neutralizing antibodies constitutes an important first step in the development of therapeutic agents that could be used to counter the effects of the epsilon-toxin. PMID:17261609

  4. Virulence gene profiles of shiga toxin-producing Escherichia coli isolated from fecal samples of finishing swine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Shiga toxin-producing Escherichia coli (STEC) are important pathogens responsible for food-borne outbreaks and serious illness including hemorrhagic colitis and hemolytic uremic syndrome. Certain STEC serogroups may cause edema disease in swine; and similar to cattle, swine have been shown to be a ...

  5. Risk practices for animal and human anthrax in Bangladesh: an exploratory study

    PubMed Central

    Islam, Md. Saiful; Hossain, M. Jahangir; Mikolon, Andrea; Parveen, Shahana; Khan, M. Salah Uddin; Haider, Najmul; Chakraborty, Apurba; Titu, Abu Mohammad Naser; Rahman, M. Waliur; Sazzad, Hossain M. S.; Rahman, Mahmudur; Gurley, Emily S.; Luby, Stephen P.

    2013-01-01

    Introduction From August 2009 to October 2010, International Centre for Diarrheal Disease Research, Bangladesh and the Institute of Epidemiology, Disease Control and Research together investigated 14 outbreaks of anthrax which included 140 animal and 273 human cases in 14 anthrax-affected villages. Our investigation objectives were to explore the context in which these outbreaks occurred, including livestock rearing practices, human handling of sick and dead animals, and the anthrax vaccination program. Methods Field anthropologists used qualitative data-collection tools, including 15 hours of unstructured observations, 11 key informant interviews, 32 open-ended interviews, and 6 group discussions in 5 anthrax-affected villages. Results Each cattle owner in the affected communities raised a median of six ruminants on their household premises. The ruminants were often grazed in pastures and fed supplementary rice straw, green grass, water hyacinth, rice husk, wheat bran, and oil cake; lactating cows were given dicalcium phosphate. Cattle represented a major financial investment. Since Islamic law forbids eating animals that die from natural causes, when anthrax-infected cattle were moribund, farmers often slaughtered them on the household premises while they were still alive so that the meat could be eaten. Farmers ate the meat and sold it to neighbors. Skinners removed and sold the hides from discarded carcasses. Farmers discarded the carcasses and slaughtering waste into ditches, bodies of water, or open fields. Cattle in the affected communities did not receive routine anthrax vaccine due to low production, poor distribution, and limited staffing for vaccination. Conclusion Slaughtering anthrax-infected animals and disposing of butchering waste and carcasses in environments where ruminants live and graze, combined with limited vaccination, provided a context that permitted repeated anthrax outbreaks in animals and humans. Because of strong financial incentives

  6. Mapping the Distribution of Anthrax in Mainland China, 2005–2013

    PubMed Central

    Yang, Yang; Liu, Kun; Li, Xin-Lou; Yao, Hong-Wu; Li, Yu; Zhou, Hang; Wang, Li-Ping; Mu, Di; Yin, Wen-Wu; Fang, Li-Qun; Yu, Hong-Jie; Cao, Wu-Chun

    2016-01-01

    Background Anthrax, a global re-emerging zoonotic disease in recent years is enzootic in mainland China. Despite its significance to the public health, spatiotemporal distributions of the disease in human and livestock and its potential driving factors remain poorly understood. Methodology/Principal Findings Using the national surveillance data of human and livestock anthrax from 2005 to 2013, we conducted a retrospective epidemiological study and risk assessment of anthrax in mainland China. The potential determinants for the temporal and spatial distributions of human anthrax were also explored. We found that the majority of human anthrax cases were located in six provinces in western and northeastern China, and five clustering areas with higher incidences were identified. The disease mostly peaked in July or August, and males aged 30–49 years had higher incidence than other subgroups. Monthly incidence of human anthrax was positively correlated with monthly average temperature, relative humidity and monthly accumulative rainfall with lags of 0–2 months. A boosted regression trees (BRT) model at the county level reveals that densities of cattle, sheep and human, coverage of meadow, coverage of typical grassland, elevation, coverage of topsoil with pH > 6.1, concentration of organic carbon in topsoil, and the meteorological factors have contributed substantially to the spatial distribution of the disease. The model-predicted probability of occurrence of human cases in mainland China was mapped at the county level. Conclusions/Significance Anthrax in China was characterized by significant seasonality and spatial clustering. The spatial distribution of human anthrax was largely driven by livestock husbandry, human density, land cover, elevation, topsoil features and climate. Enhanced surveillance and intervention for livestock and human anthrax in the high-risk regions, particularly on the Qinghai-Tibetan Plateau, is the key to the prevention of human infections

  7. Pre-Columbian origins for North American anthrax.

    PubMed

    Kenefic, Leo J; Pearson, Talima; Okinaka, Richard T; Schupp, James M; Wagner, David M; Hoffmaster, Alex R; Trim, Carla B; Trim, Carla P; Chung, Wai-Kwan; Beaudry, Jodi A; Jiang, Lingxia; Gajer, Pawel; Foster, Jeffrey T; Mead, James I; Ravel, Jacques; Keim, Paul

    2009-01-01

    Disease introduction into the New World during colonial expansion is well documented and had a major impact on indigenous populations; however, few diseases have been associated with early human migrations into North America. During the late Pleistocene epoch, Asia and North America were joined by the Beringian Steppe ecosystem which allowed animals and humans to freely cross what would become a water barrier in the Holocene. Anthrax has clearly been shown to be dispersed by human commerce and trade in animal products contaminated with Bacillus anthracis spores. Humans appear to have brought B. anthracis to this area from Asia and then moved it further south as an ice-free corridor opened in central Canada approximately 13,000 ybp. In this study, we have defined the evolutionary history of Western North American (WNA) anthrax using 2,850 single nucleotide polymorphisms (SNPs) and 285 geographically diverse B. anthracis isolates. Phylogeography of the major WNA B. anthracis clone reveals ancestral populations in northern Canada with progressively derived populations to the south; the most recent ancestor of this clonal lineage is in Eurasia. Our phylogeographic patterns are consistent with B. anthracis arriving with humans via the Bering Land Bridge. This northern-origin hypothesis is highly consistent with our phylogeographic patterns and rates of SNP accumulation observed in current day B. anthracis isolates. Continent-wide dispersal of WNA B. anthracis likely required movement by later European colonizers, but the continent's first inhabitants may have seeded the initial North American populations. PMID:19283072

  8. Rabies virus glycoprotein as a carrier for anthrax protective antigen

    SciTech Connect

    Smith, Mary Ellen; Koser, Martin; Xiao Sa; Siler, Catherine; McGettigan, James P.; Calkins, Catherine; Pomerantz, Roger J.; Dietzschold, Bernhard; Schnell, Matthias J. . E-mail: matthias.schnell@jefferson.edu

    2006-09-30

    Live viral vectors expressing foreign antigens have shown great promise as vaccines against viral diseases. However, safety concerns remain a major problem regarding the use of even highly attenuated viral vectors. Using the rabies virus (RV) envelope protein as a carrier molecule, we show here that inactivated RV particles can be utilized to present Bacillus anthracis protective antigen (PA) domain-4 in the viral membrane. In addition to the RV glycoprotein (G) transmembrane and cytoplasmic domains, a portion of the RV G ectodomain was required to express the chimeric RV G anthrax PA on the cell surface. The novel antigen was also efficiently incorporated into RV virions. Mice immunized with the inactivated recombinant RV virions exhibited seroconversion against both RV G and anthrax PA, and a second inoculation greatly increased these responses. These data demonstrate that a viral envelope protein can carry a bacterial protein and that a viral carrier can display whole polypeptides compared to the limited epitope presentation of previous viral systems.

  9. Pre-Columbian Origins for North American Anthrax

    PubMed Central

    Okinaka, Richard T.; Schupp, James M.; Wagner, David M.; Ravel, Jacques; Hoffmaster, Alex R.; Trim, Carla P.; Chung, Wai-Kwan; Beaudry, Jodi A.; Foster, Jeffrey T.; Mead, James I.; Keim, Paul

    2009-01-01

    Disease introduction into the New World during colonial expansion is well documented and had a major impact on indigenous populations; however, few diseases have been associated with early human migrations into North America. During the late Pleistocene epoch, Asia and North America were joined by the Beringian Steppe ecosystem which allowed animals and humans to freely cross what would become a water barrier in the Holocene. Anthrax has clearly been shown to be dispersed by human commerce and trade in animal products contaminated with Bacillus anthracis spores. Humans appear to have brought B. anthracis to this area from Asia and then moved it further south as an ice-free corridor opened in central Canada ∼13,000 ybp. In this study, we have defined the evolutionary history of Western North American (WNA) anthrax using 2,850 single nucleotide polymorphisms (SNPs) and 285 geographically diverse B. anthracis isolates. Phylogeography of the major WNA B. anthracis clone reveals ancestral populations in northern Canada with progressively derived populations to the south; the most recent ancestor of this clonal lineage is in Eurasia. Our phylogeographic patterns are consistent with B. anthracis arriving with humans via the Bering Land Bridge. This northern-origin hypothesis is highly consistent with our phylogeographic patterns and rates of SNP accumulation observed in current day B. anthracis isolates. Continent-wide dispersal of WNA B. anthracis likely required movement by later European colonizers, but the continent's first inhabitants may have seeded the initial North American populations. PMID:19283072

  10. Fidaxomicin Inhibits Clostridium difficile Toxin A-Mediated Enteritis in the Mouse Ileum

    PubMed Central

    Koon, Hon Wai; Ho, Samantha; Hing, Tressia C.; Cheng, Michelle; Chen, Xinhua; Ichikawa, Yoshi; Kelly, Ciarán P.

    2014-01-01

    Clostridium difficile infection (CDI) is a common, debilitating infection with high morbidity and mortality. C. difficile causes diarrhea and intestinal inflammation by releasing two toxins, toxin A and toxin B. The macrolide antibiotic fidaxomicin was recently shown to be effective in treating CDI, and its beneficial effect was associated with fewer recurrent infections in CDI patients. Since other macrolides possess anti-inflammatory properties, we examined the possibility that fidaxomicin alters C. difficile toxin A-induced ileal inflammation in mice. The ileal loops of anesthetized mice were injected with fidaxomicin (5, 10, or 20 μM), and after 30 min, the loops were injected with purified C. difficile toxin A or phosphate-buffered saline alone. Four hours after toxin A administration, ileal tissues were processed for histological evaluation (epithelial cell damage, neutrophil infiltration, congestion, and edema) and cytokine measurements. C. difficile toxin A caused histologic damage, evidenced by increased mean histologic score and ileal interleukin-1β (IL-1β) protein and mRNA expression. Treatment with fidaxomicin (20 μM) or its primary metabolite, OP-1118 (120 μM), significantly inhibited toxin A-mediated histologic damage and reduced the mean histology score and ileal IL-1β protein and mRNA expression. Both fidaxomicin and OP-1118 reduced toxin A-induced cell rounding in human colonic CCD-18Co fibroblasts. Treatment of ileal loops with vancomycin (20 μM) and metronidazole (20 μM) did not alter toxin A-induced histologic damage and IL-1β protein expression. In addition to its well known antibacterial effects against C. difficile, fidaxomicin may possess anti-inflammatory activity directed against the intestinal effects of C. difficile toxins. PMID:24890583

  11. Fidaxomicin inhibits Clostridium difficile toxin A-mediated enteritis in the mouse ileum.

    PubMed

    Koon, Hon Wai; Ho, Samantha; Hing, Tressia C; Cheng, Michelle; Chen, Xinhua; Ichikawa, Yoshi; Kelly, Ciarán P; Pothoulakis, Charalabos

    2014-08-01

    Clostridium difficile infection (CDI) is a common, debilitating infection with high morbidity and mortality. C. difficile causes diarrhea and intestinal inflammation by releasing two toxins, toxin A and toxin B. The macrolide antibiotic fidaxomicin was recently shown to be effective in treating CDI, and its beneficial effect was associated with fewer recurrent infections in CDI patients. Since other macrolides possess anti-inflammatory properties, we examined the possibility that fidaxomicin alters C. difficile toxin A-induced ileal inflammation in mice. The ileal loops of anesthetized mice were injected with fidaxomicin (5, 10, or 20 μM), and after 30 min, the loops were injected with purified C. difficile toxin A or phosphate-buffered saline alone. Four hours after toxin A administration, ileal tissues were processed for histological evaluation (epithelial cell damage, neutrophil infiltration, congestion, and edema) and cytokine measurements. C. difficile toxin A caused histologic damage, evidenced by increased mean histologic score and ileal interleukin-1β (IL-1β) protein and mRNA expression. Treatment with fidaxomicin (20 μM) or its primary metabolite, OP-1118 (120 μM), significantly inhibited toxin A-mediated histologic damage and reduced the mean histology score and ileal IL-1β protein and mRNA expression. Both fidaxomicin and OP-1118 reduced toxin A-induced cell rounding in human colonic CCD-18Co fibroblasts. Treatment of ileal loops with vancomycin (20 μM) and metronidazole (20 μM) did not alter toxin A-induced histologic damage and IL-1β protein expression. In addition to its well known antibacterial effects against C. difficile, fidaxomicin may possess anti-inflammatory activity directed against the intestinal effects of C. difficile toxins. PMID:24890583

  12. Agonist of growth hormone-releasing hormone reduces pneumolysin-induced pulmonary permeability edema

    PubMed Central

    Lucas, Rudolf; Sridhar, Supriya; Rick, Ferenc G.; Gorshkov, Boris; Umapathy, Nagavedi S.; Yang, Guang; Oseghale, Aluya; Verin, Alexander D.; Chakraborty, Trinad; Matthay, Michael A.; Zemskov, Evgeny A.; White, Richard; Block, Norman L.; Schally, Andrew V.

    2012-01-01

    Aggressive treatment with antibiotics in patients infected with Streptococcus pneumoniae induces release of the bacterial virulence factor pneumolysin (PLY). Days after lungs are sterile, this pore-forming toxin can still induce pulmonary permeability edema in patients, characterized by alveolar/capillary barrier dysfunction and impaired alveolar liquid clearance (ALC). ALC is mainly regulated through Na+ transport by the apically expressed epithelial sodium channel (ENaC) and the basolaterally expressed Na+/K+-ATPase in type II alveolar epithelial cells. Because no standard treatment is currently available to treat permeability edema, the search for novel therapeutic candidates is of high priority. We detected mRNA expression for the active receptor splice variant SV1 of the hypothalamic polypeptide growth hormone-releasing hormone (GHRH), as well as for GHRH itself, in human lung microvascular endothelial cells (HL-MVEC). Therefore, we have evaluated the effect of the GHRH agonist JI-34 on PLY-induced barrier and ALC dysfunction. JI-34 blunts PLY-mediated endothelial hyperpermeability in monolayers of HL-MVEC, in a cAMP-dependent manner, by means of reducing the phosphorylation of myosin light chain and vascular endothelial (VE)-cadherin. In human airway epithelial H441 cells, PLY significantly impairs Na+ uptake, but JI-34 restores it to basal levels by means of increasing cAMP levels. Intratracheal instillation of PLY into C57BL6 mice causes pulmonary alveolar epithelial and endothelial hyperpermeability as well as edema formation, all of which are blunted by JI-34. These findings point toward a protective role of the GHRH signaling pathway in PLY-induced permeability edema. PMID:22308467

  13. Influenza leaves a TRAIL to pulmonary edema.

    PubMed

    Brauer, Rena; Chen, Peter

    2016-04-01

    Influenza infection can cause acute respiratory distress syndrome (ARDS), leading to poor disease outcome with high mortality. One of the driving features in the pathogenesis of ARDS is the accumulation of fluid in the alveoli, which causes severe pulmonary edema and impaired oxygen uptake. In this issue of the JCI, Peteranderl and colleagues define a paracrine communication between macrophages and type II alveolar epithelial cells during influenza infection where IFNα induces macrophage secretion of TRAIL that causes endocytosis of Na,K-ATPase by the alveolar epithelium. This reduction of Na,K-ATPase expression decreases alveolar fluid clearance, which in turn leads to pulmonary edema. Inhibition of the TRAIL signaling pathway has been shown to improve lung injury after influenza infection, and future studies will be needed to determine if blocking this pathway is a viable option in the treatment of ARDS. PMID:26999598

  14. Management of pseudophakic cystoid macular edema.

    PubMed

    Guo, Suqin; Patel, Shriji; Baumrind, Ben; Johnson, Keegan; Levinsohn, Daniel; Marcus, Edward; Tannen, Brad; Roy, Monique; Bhagat, Neelakshi; Zarbin, Marco

    2015-01-01

    Pseudophakic cystoid macular edema (PCME) is a common complication following cataract surgery. Acute PCME may resolve spontaneously, but some patients will develop chronic macular edema that affects vision and is difficult to treat. This disease was described more than 50 years ago, and there are multiple options for clinical management. We discuss mechanisms, clinical efficacy, and adverse effects of these treatment modalities. Topical non-steroidal anti-inflammatory agents and corticosteroids are widely used and, when combined, may have a synergistic effect. Intravitreal corticosteroids and anti-vascular endothelial growth factor (anti-VEGF) agents have shown promise when topical medications either fail or have had limited effects. Randomized clinical studies evaluating anti-VEGF agents are needed to fully evaluate benefits and risks. When PCME is either refractory to medical therapy or is associated with significant vitreous involvement, pars plana vitrectomy has been shown to improve outcomes, though it is associated with additional risks. PMID:25438734

  15. The evolution of scuba divers pulmonary edema.

    PubMed

    Edmonds, Carl

    2016-01-01

    The evolution of scuba divers pulmonary edema is described. When discovered in 1981, it was believed to be a cold-induced response in a submerged, otherwise healthy, scuba diver. The clinical features are described and discussed, as are the demographics. An alleged prevalence of 1.1% was complicated by problematic statistics and an apparent increase in reported cases. Recurrences both while diving and swimming or snorkeling were common. More recent case reports and surveys are described, identifying predisposing factors and associations, including cardiac pathology. Stress cardiomyopathies, reversible myocardial disorder or Takotsubo cardiomyopathy, may complicate the presentation, especially in older females. Relevant cardiac investigations and autopsy findings are reviewed. Disease severity and potential lethality of scuba divers pulmonary edema became more apparent early this century, and these influence our current recommendations to survivors. First aid and treatment are also discussed. PMID:27265985

  16. Identification and Validation of a Linear Protective Neutralizing Epitope in the β-Pore Domain of Alpha Toxin

    PubMed Central

    Oscherwitz, Jon; Cease, Kemp B.

    2015-01-01

    The plethora of virulence factors associated with Staphylococcus aureus make this bacterium an attractive candidate for a molecularly-designed epitope-focused vaccine. This approach, which necessitates the identification of neutralizing epitopes for incorporation into a vaccine construct, is being evaluated for pathogens where conventional approaches have failed to elicit protective humoral responses, like HIV-1 and malaria, but may also hold promise for pathogens like S. aureus, where the elicitation of humoral immunity against multiple virulence factors may be required for development of an effective vaccine. Among the virulence factors employed by S. aureus, animal model and epidemiological data suggest that alpha toxin, a multimeric β-pore forming toxin like protective antigen from Bacillus anthracis, is particularly critical, yet no candidate neutralizing epitopes have been delineated in alpha toxin to date. We have previously shown that a linear determinant in the 2β2-2β3 loop of the pore forming domain of B. anthracis protective antigen is a linear neutralizing epitope. Antibody against this site is highly potent for neutralizing anthrax lethal toxin in vitro and for protection of rabbits in vivo from virulent B. anthracis. We hypothesized that sequences in the β-pore of S. aureus alpha toxin that share structural and functional homology to β-pore sequences in protective antigen would contain a similarly critical neutralizing epitope. Using an in vivo mapping strategy employing peptide immunogens, an optimized in vitro toxin neutralization assay, and an in vivo dermonecrosis model, we have now confirmed the presence of this epitope in alpha toxin, termed the pore neutralizing determinant. Antibody specific for this determinant neutralizes alpha toxin in vitro, and is highly effective for mitigating dermonecrosis and bacterial growth in a mouse model of S. aureus USA300 skin infection. The delineation of this linear neutralizing determinant in alpha

  17. Identification and validation of a linear protective neutralizing epitope in the β-pore domain of alpha toxin.

    PubMed

    Oscherwitz, Jon; Cease, Kemp B

    2015-01-01

    The plethora of virulence factors associated with Staphylococcus aureus make this bacterium an attractive candidate for a molecularly-designed epitope-focused vaccine. This approach, which necessitates the identification of neutralizing epitopes for incorporation into a vaccine construct, is being evaluated for pathogens where conventional approaches have failed to elicit protective humoral responses, like HIV-1 and malaria, but may also hold promise for pathogens like S. aureus, where the elicitation of humoral immunity against multiple virulence factors may be required for development of an effective vaccine. Among the virulence factors employed by S. aureus, animal model and epidemiological data suggest that alpha toxin, a multimeric β-pore forming toxin like protective antigen from Bacillus anthracis, is particularly critical, yet no candidate neutralizing epitopes have been delineated in alpha toxin to date. We have previously shown that a linear determinant in the 2β2-2β3 loop of the pore forming domain of B. anthracis protective antigen is a linear neutralizing epitope. Antibody against this site is highly potent for neutralizing anthrax lethal toxin in vitro and for protection of rabbits in vivo from virulent B. anthracis. We hypothesized that sequences in the β-pore of S. aureus alpha toxin that share structural and functional homology to β-pore sequences in protective antigen would contain a similarly critical neutralizing epitope. Using an in vivo mapping strategy employing peptide immunogens, an optimized in vitro toxin neutralization assay, and an in vivo dermonecrosis model, we have now confirmed the presence of this epitope in alpha toxin, termed the pore neutralizing determinant. Antibody specific for this determinant neutralizes alpha toxin in vitro, and is highly effective for mitigating dermonecrosis and bacterial growth in a mouse model of S. aureus USA300 skin infection. The delineation of this linear neutralizing determinant in alpha

  18. Emerging Pharmacotherapies for Diabetic Macular Edema

    PubMed Central

    Javey, Golnaz; Schwartz, Stephen G.; Flynn, Harry W.

    2012-01-01

    Diabetic macular edema (DME) remains an important cause of visual loss in patients with diabetes mellitus. Although photocoagulation and intensive control of systemic metabolic factors have been reported to achieve improved outcomes in large randomized clinical trials (RCTs), some patients with DME continue to lose vision despite treatment. Pharmacotherapies for DME include locally and systemically administered agents. We review several agents that have been studied for the treatment of DME. PMID:22474425

  19. Cystoid Macular Edema in Bietti's Crystalline Retinopathy

    PubMed Central

    2014-01-01

    A 27-year-old man with progressive bilateral visual decline was diagnosed to have Bietti's crystalline dystrophy (BCD). Fluorescein angiography revealed bilateral petaloid type late hyperfluorescence implicating concurrent cystoid macular edema (CME). Optical coherence tomography exhibited cystoid foveal lacunas OU. During the follow-up of six years, intraretinal crystals reduced in amount but CME persisted angiographically and tomographically. CME is among the rare macular features of BCD including subfoveal sensorial detachment, subretinal neovascular membrane, and macular hole. PMID:24949209

  20. An unusual cause of pulmonary edema.

    PubMed

    Chong, Adrian; Wahi, Sudhir; Harvey, Ryan; Finn, Chris; Shah, Pallav; Gould, Paul

    2014-03-01

    Primary cardiac tumors are rare malignancies. Patients may present with congestive cardiac failure due to intracavitary obstruction to blood flow, valvular dysfunction, embolic phenomena, local invasion resulting in arrhythmias, pericardial involvement, constitutional symptoms, or paraneoplastic syndromes. We describe the case of a previously fit 79-year-old woman who presented with acute pulmonary edema due to a large left atrial pleomorphic sarcoma causing severe functional mitral stenosis. She underwent palliative debulking surgery with good symptomatic relief. PMID:24585913

  1. Naturally Occurring Food Toxins

    PubMed Central

    Dolan, Laurie C.; Matulka, Ray A.; Burdock, George A.

    2010-01-01

    Although many foods contain toxins as a naturally-occurring constituent or, are formed as the result of handling or processing, the incidence of adverse reactions to food is relatively low. The low incidence of adverse effects is the result of some pragmatic solutions by the US Food and Drug Administration (FDA) and other regulatory agencies through the creative use of specifications, action levels, tolerances, warning labels and prohibitions. Manufacturers have also played a role by setting limits on certain substances and developing mitigation procedures for process-induced toxins. Regardless of measures taken by regulators and food producers to protect consumers from natural food toxins, consumption of small levels of these materials is unavoidable. Although the risk for toxicity due to consumption of food toxins is fairly low, there is always the possibility of toxicity due to contamination, overconsumption, allergy or an unpredictable idiosyncratic response. The purpose of this review is to provide a toxicological and regulatory overview of some of the toxins present in some commonly consumed foods, and where possible, discuss the steps that have been taken to reduce consumer exposure, many of which are possible because of the unique process of food regulation in the United States. PMID:22069686

  2. High altitude pulmonary edema in mountain climbers.

    PubMed

    Korzeniewski, Krzysztof; Nitsch-Osuch, Aneta; Guzek, Aneta; Juszczak, Dariusz

    2015-04-01

    Every year thousands of ski, trekking or climbing fans travel to the mountains where they stay at the altitude of more than 2500-3000m above sea level or climb mountain peaks, often exceeding 7000-8000m. High mountain climbers are at a serious risk from the effects of adverse environmental conditions prevailing at higher elevations. They may experience health problems resulting from hypotension, hypoxia or exposure to low temperatures; the severity of those conditions is largely dependent on elevation, time of exposure as well as the rate of ascent and descent. A disease which poses a direct threat to the lives of mountain climbers is high altitude pulmonary edema (HAPE). It is a non-cardiogenic pulmonary edema which typically occurs in rapidly climbing unacclimatized lowlanders usually within 2-4 days of ascent above 2500-3000m. It is the most common cause of death resulting from the exposure to high altitude. The risk of HAPE rises with increased altitude and faster ascent. HAPE incidence ranges from an estimated 0.01% to 15.5%. Climbers with a previous history of HAPE, who ascent rapidly above 4500m have a 60% chance of illness recurrence. The aim of this article was to present the relevant details concerning epidemiology, pathophysiology, clinical symptoms, prevention, and treatment of high altitude pulmonary edema among climbers in the mountain environment. PMID:25291181

  3. Genome Sequence of Bacillus anthracis Strain Stendal, Isolated from an Anthrax Outbreak in Cattle in Germany

    PubMed Central

    Elschner, Mandy; Gaede, Wolfgang; Schliephake, Annette; Grass, Gregor; Tomaso, Herbert

    2016-01-01

    In July 2012, an anthrax outbreak occurred among cattle in northern Germany resulting in ten losses. Here, we report the draft genome sequence of Bacillus anthracis strain Stendal, isolated from one of the diseased cows. PMID:27056225

  4. Genome Sequence of Bacillus anthracis Strain Stendal, Isolated from an Anthrax Outbreak in Cattle in Germany.

    PubMed

    Antwerpen, Markus; Elschner, Mandy; Gaede, Wolfgang; Schliephake, Annette; Grass, Gregor; Tomaso, Herbert

    2016-01-01

    In July 2012, an anthrax outbreak occurred among cattle in northern Germany resulting in ten losses. Here, we report the draft genome sequence ofBacillus anthracisstrain Stendal, isolated from one of the diseased cows. PMID:27056225

  5. 9 CFR 311.10 - Anaplasmosis, anthrax, babesiosis, bacillary hemoglobinuria in cattle, blackleg, bluetongue...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., infectious bovine rhinotracheitis, leptospirosis, malignant epizootic catarrh, strangles, purpura..., purpura hemorrhagica, azoturia, infectious equine encephalomyelitis, toxic encephalomyelitis (forage... condemned: (1) Anthrax. (2) Blackleg. (3) Unhealed vaccine lesions (vaccinia). (4) Strangles. (5)...

  6. 9 CFR 311.10 - Anaplasmosis, anthrax, babesiosis, bacillary hemoglobinuria in cattle, blackleg, bluetongue...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., infectious bovine rhinotracheitis, leptospirosis, malignant epizootic catarrh, strangles, purpura..., purpura hemorrhagica, azoturia, infectious equine encephalomyelitis, toxic encephalomyelitis (forage... condemned: (1) Anthrax. (2) Blackleg. (3) Unhealed vaccine lesions (vaccinia). (4) Strangles. (5)...

  7. 9 CFR 311.10 - Anaplasmosis, anthrax, babesiosis, bacillary hemoglobinuria in cattle, blackleg, bluetongue...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., infectious bovine rhinotracheitis, leptospirosis, malignant epizootic catarrh, strangles, purpura..., purpura hemorrhagica, azoturia, infectious equine encephalomyelitis, toxic encephalomyelitis (forage... condemned: (1) Anthrax. (2) Blackleg. (3) Unhealed vaccine lesions (vaccinia). (4) Strangles. (5)...

  8. Characterizing a “New” Disease: Epizootic and Epidemic Anthrax, 1769–1780

    PubMed Central

    Morens, David M.

    2003-01-01

    In 1876, Robert Koch established anthrax as the first disease linked to a microbial agent. But Koch’s efforts had followed more than 150 years of scientific progress in characterizing anthrax as a specific human and veterinary disease. Focusing on France and the period between 1769 and 1780, this brief review examines noteworthy early events in the characterization of anthrax. It suggests that some “new” diseases like anthrax might be “discovered” not only by luck, brilliance, or new technologies, but by clinical/epidemiological “puzzle-fitting,” which can assemble a cohesive picture of a seemingly specific disease entity. If such processes have operated over 2 or more centuries, studying them may yield clues about desirable interactions between epidemiology/public health and experimental science in the characterization of new diseases. PMID:12773345

  9. Anthrax control and research, with special reference to national programme development in Africa: memorandum from a WHO meeting.

    PubMed Central

    1994-01-01

    The prevalence of anthrax in both animal and human populations has been increasing in Africa. It was therefore appropriate for this WHO meeting to be convened in an endemic area of the Western Province of Zambia in 1992. The participants reviewed anthrax epidemiology and control in some African countries, elaborated national anthrax control and research programmes in Africa, discussed international cooperation and work plans, and elaborated recommendations for anthrax control in Africa. The discussions centred on anthrax surveillance and reporting systems, diagnosis, vaccine production and immunization, disinfection and decontamination, carcass disposal, treatment of human cases, health systems, as well as intersectorial cooperation between public health services, veterinary services and other services such as wildlife conservation, so that national control programmes could take full account of the conditions prevailing in epidemic situations in Africa. The recommendations are applicable in other regions where anthrax poses similar problems in public, animal and environmental health. PMID:8131249

  10. Lessons for Control of Heroin-Associated Anthrax in Europe from 2009–2010 Outbreak Case Studies, London, UK

    PubMed Central

    Abbara, Aula; Brooks, Tim; Taylor, Graham P.; Nolan, Marianne; Donaldson, Hugo; Manikon, Maribel

    2014-01-01

    Outbreaks of serious infections associated with heroin use in persons who inject drugs (PWIDs) occur intermittently and require vigilance and rapid reporting of individual cases. Here, we give a firsthand account of the cases in London during an outbreak of heroin-associated anthrax during 2009–2010 in the United Kingdom. This new manifestation of anthrax has resulted in a clinical manifestation distinct from already recognized forms. During 2012–13, additional cases of heroin-associated anthrax among PWIDs in England and other European countries were reported, suggesting that anthrax-contaminated heroin remains in circulation. Antibacterial drugs used for serious soft tissue infection are effective against anthrax, which may lead to substantial underrecognition of this novel illness. The outbreak in London provides a strong case for ongoing vigilance and the use of serologic testing in diagnosis and serologic surveillance schemes to determine and monitor the prevalence of anthrax exposure in the PWID community. PMID:24959910

  11. Brain lesions associated with clostridium perfringens type D epsilon toxin in a Holstein heifer calf.

    PubMed

    Mete, A; Garcia, J; Ortega, J; Lane, M; Scholes, S; Uzal, F A

    2013-09-01

    A 6-month-old dairy heifer calf with no premonitory signs was acutely down after the morning feeding and could not rise. On presentation, the heifer was in right lateral recumbency and moribund with opisthotonus and left hind limb paddling. Following euthanasia, gross examination of the brain revealed multifocal loss of gray-white matter distinction and extensive petechiae throughout the brainstem. On histopathological examination, there was striking white matter edema and marked perivascular proteinaceous edema surrounding many arterioles and venules (microangiopathy), mainly in the white matter of the internal capsule, thalamus, midbrain, cerebellum, and cerebellar peduncles. The perivascular neuropil was strongly positive for Alzheimer precursor protein A4. Clostridium perfringens epsilon toxin was detected in the intestinal contents. This is the first report of microangiopathy in postneonatal cattle associated with the detection of epsilon toxin in the intestinal contents. PMID:23381925

  12. Investigation of Anthrax Cases in North-East China, 2010-2014

    PubMed Central

    Zhou, Wei; Sun, Yang; Zhu, Lingwei; Zhou, Bo; Liu, Jun; Ji, Xue; Wang, Xiaofeng; Wang, Nan; Gu, Guibo; Feng, Shuzhang; Qian, Jun; Guo, Xuejun

    2015-01-01

    We determined the genotypes of seven Bacillus anthracis strains that were recovered from nine anthrax outbreaks in North-East China from 2010 to 2014, and two approved vaccine strains that are currently in use in China. The causes of these cases were partly due to local farmers being unaware of the presence of anthrax, and butchers with open wounds having direct contact with anthrax-contaminated meat products. The genotype of five of the seven recovered strains was A.Br.001/002 sub-lineage, which was concordant with previously published research. The remaining two cases belongs to the A.Br.Ames sub-lineage. Both of these strains displayed an identical SNR pattern, which was the first time that this genotype was identified in North-East China. Strengthening education in remote villages of rural China is an important activity aimed at fostering attempts to prevent and control anthrax. The genotype of the vaccine strain Anthrax Spore Vaccine No.II was A.Br.008/009 and A.Br.001/002 for the vaccine strain Anthrax Spore Vaccine Non-capsulated. Further studies of their characteristics are clearly warranted. PMID:26308449

  13. The Physiologic Responses of Dutch Belted Rabbits Infected with Inhalational Anthrax

    PubMed Central

    Lawrence, William S; Hardcastle, Jason M; Brining, Douglas L; Weaver, Lori E; Ponce, Cindy; Whorton, Elbert B; Peterson, Johnny W

    2009-01-01

    Bacillus anthracis, the causative agent of anthrax, is a category A priority pathogen that causes extensive damage in humans. For this reason, B. anthracis has been the focus of numerous studies using various animal models. In this study, we explored physiologic parameters in Dutch belted rabbits with inhalation anthrax to characterize the disease progression in this model. To this end, we infected Dutch belted rabbits with 100 LD50 B. anthracis Ames spores by nasal instillation and continuously recorded various physiologic parameters by using telemetry. In addition, samples were collected at selected times for serum chemistry, hematology, and blood gas analysis. The animals exhibited hemodynamic and respiratory changes that coincided with those reported in human cases of inhalational anthrax infection, including hypotension, altered heart rate, and respiratory distress. Likewise, hematology, serum chemistry, and blood gas analysis revealed trends comparable to human anthrax-related pathophysiology. The Dutch belted rabbit model of inhalational anthrax exhibited most of the physiologic, hematologic, and biochemical sequelae noted in human cases. Therefore, this rabbit model fulfills several of the criteria of a useful animal model for studying disease pathogenesis and evaluating therapeutics during inhalational anthrax. PMID:19619416

  14. Investigation of Anthrax Cases in North-East China, 2010-2014.

    PubMed

    Zhou, Wei; Sun, Yang; Zhu, Lingwei; Zhou, Bo; Liu, Jun; Ji, Xue; Wang, Xiaofeng; Wang, Nan; Gu, Guibo; Feng, Shuzhang; Qian, Jun; Guo, Xuejun

    2015-01-01

    We determined the genotypes of seven Bacillus anthracis strains that were recovered from nine anthrax outbreaks in North-East China from 2010 to 2014, and two approved vaccine strains that are currently in use in China. The causes of these cases were partly due to local farmers being unaware of the presence of anthrax, and butchers with open wounds having direct contact with anthrax-contaminated meat products. The genotype of five of the seven recovered strains was A.Br.001/002 sub-lineage, which was concordant with previously published research. The remaining two cases belongs to the A.Br.Ames sub-lineage. Both of these strains displayed an identical SNR pattern, which was the first time that this genotype was identified in North-East China. Strengthening education in remote villages of rural China is an important activity aimed at fostering attempts to prevent and control anthrax. The genotype of the vaccine strain Anthrax Spore Vaccine No.II was A.Br.008/009 and A.Br.001/002 for the vaccine strain Anthrax Spore Vaccine Non-capsulated. Further studies of their characteristics are clearly warranted. PMID:26308449

  15. Current status of immunization against anthrax: old vaccines may be here to stay for a while.

    PubMed

    Turnbull, Peter C.B.

    2000-04-01

    Anthrax vaccination has become a 'hot' topic. On the one hand, fears that Iraq holds secret caches of anthrax-based weaponry, that other countries may be developing or may have developed similar devices, or that hard-line groups may make their own anthrax-based devices for bioterrorist attacks have focused official attention on the need for means of protection, principally, though, for the military. On the other hand, the unsolved issues of the Gulf War illnesses have left elements of doubt in the minds of some as to the possible role of anthrax (among other) vaccines in this syndrome, and have drawn attention to the shortage of pre-clinical, clinical, pharmacological and safety data on the existing UK and US anthrax vaccines. In the middle are those hotly debating the US and Canadian policies of mandatory anthrax immunization for military personnel or, in the case of the UK policy of voluntary immunization, simply voting with their feet. Compounding matters have been the publicized failures of the US vaccine production facility and the less publicized UK problems of supply. Meanwhile, those in genuine at-risk occupations are left unsure whether, if they can get the vaccine at all, they really want it. Despite two decades of elegant science aimed at formulating alternative vaccines to overcome all the problems of efficacy, safety and supply, such an alternative is at least five years away, and the current status is that we must live with the old vaccines or not vaccinate. PMID:11964777

  16. PemK Toxin of Bacillus anthracis Is a Ribonuclease

    PubMed Central

    Agarwal, Shivangi; Mishra, Neeraj Kumar; Bhatnagar, Sonika; Bhatnagar, Rakesh

    2010-01-01

    Bacillus anthracis genome harbors a toxin-antitoxin (TA) module encoding pemI (antitoxin) and pemK (toxin). This study describes the rPemK as a potent ribonuclease with a preference for pyrimidines (C/U), which is consistent with our previous study that demonstrated it as a translational attenuator. The in silico structural modeling of the PemK in conjunction with the site-directed mutagenesis confirmed the role of His-59 and Glu-78 as an acid-base couple in mediating the ribonuclease activity. The rPemK is shown to form a complex with the rPemI, which is in line with its function as a TA module. This rPemI-rPemK complex becomes catalytically inactive when both the proteins interact in a molar stoichiometry of 1. The rPemI displays vulnerability to proteolysis but attains conformational stability only upon rPemK interaction. The pemI-pemK transcript is shown to be up-regulated upon stress induction with a concomitant increase in the amount of PemK and a decline in the PemI levels, establishing the role of these modules in stress. The artificial perturbation of TA interaction could unleash the toxin, executing bacterial cell death. Toward this end, synthetic peptides are designed to disrupt the TA interaction. The peptides are shown to be effective in abrogating TA interaction in micromolar range in vitro. This approach can be harnessed as a potential antibacterial strategy against anthrax in the future. PMID:20022964

  17. [Toxins as a biological weapon].

    PubMed

    Płusa, Tadeusz

    2015-09-01

    The criteria for recognizing a chemical compound for the toxin are vague and gave it the possibility of inclusion in this group a number of biological agents. Toxins list is extensive, but the interest is focused on bacterial toxins, poisons derived from snake venoms, algae and plant proteins, and small molecules. Particular attention is focused on the so-called "sea" toxins, which include tetrodotoxin, brevetoxin and saxitoxin. This indicates the search for a new hitherto unknown potential bioterrorist threats. PMID:26449572

  18. Toxin plasmids of Clostridium perfringens.

    PubMed

    Li, Jihong; Adams, Vicki; Bannam, Trudi L; Miyamoto, Kazuaki; Garcia, Jorge P; Uzal, Francisco A; Rood, Julian I; McClane, Bruce A

    2013-06-01

    In both humans and animals, Clostridium perfringens is an important cause of histotoxic infections and diseases originating in the intestines, such as enteritis and enterotoxemia. The virulence of this Gram-positive, anaerobic bacterium is heavily dependent upon its prolific toxin-producing ability. Many of the ∼16 toxins produced by C. perfringens are encoded by large plasmids that range in size from ∼45 kb to ∼140 kb. These plasmid-encoded toxins are often closely associated with mobile elements. A C. perfringens strain can carry up to three different toxin plasmids, with a single plasmid carrying up to three distinct toxin genes. Molecular Koch's postulate analyses have established the importance of several plasmid-encoded toxins when C. perfringens disease strains cause enteritis or enterotoxemias. Many toxin plasmids are closely related, suggesting a common evolutionary origin. In particular, most toxin plasmids and some antibiotic resistance plasmids of C. perfringens share an ∼35-kb region containing a Tn916-related conjugation locus named tcp (transfer of clostridial plasmids). This tcp locus can mediate highly efficient conjugative transfer of these toxin or resistance plasmids. For example, conjugative transfer of a toxin plasmid from an infecting strain to C. perfringens normal intestinal flora strains may help to amplify and prolong an infection. Therefore, the presence of toxin genes on conjugative plasmids, particularly in association with insertion sequences that may mobilize these toxin genes, likely provides C. perfringens with considerable virulence plasticity and adaptability when it causes diseases originating in the gastrointestinal tract. PMID:23699255

  19. Identifying bacterial spores and anthrax hoax materials by Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Farquharson, Stuart; Brouillette, Carl R.; Smith, Wayne

    2004-12-01

    The distribution of Bacillus anthracis spores through the US postal system in the autumn of 2001, initiated a secondary form of terror, the mailing of hoax materials. In the past three years nearly 20,000 letters containing harmless powders have been mailed, creating additional anxiety. Thus, there is a need for analyzers that can not only identify anthrax-causing spores to save lives, but also identify hoax materials to eliminate time-consuming and costly shutdowns. Recently, we established that Raman spectroscopy has the ability to identify both Bacilli endospores and hoax materials. Here we present Raman spectra of several Bacilli spores along with the dipicolinate salts, to further define the abilities of this technology to not only identify hoax materials, but also identify spores at the genus and species level.

  20. Cutaneous Anthrax on Eyelid in a Pregnant Woman

    PubMed Central

    Parlak, Emine; Erturk, Ayse; Erol, Serpil; Parlak, Mehmet; Ozkurt, Zulal

    2016-01-01

    A 32-year-old patient who was 17 weeks of pregnant referred to our hospital due to a lesion on the eyelid and swelling on her face. Patient’s history revealed that she helped her husband for slaughtering of a sick animal and contacted with the meat. A scabby lesion was detected on the inferior eyelid with hyperaemia around, central necrotic appearance and swelling. The diagnosis of anthrax was performed based on her epidemiological data, physical examination findings, and Bacillus anthracis were seen on direct preparation. This case was considered worthy to present since she was pregnant, the disease was located on the inferior eyelid, which is a rare place for location, and caused no complication or sequel either in mother or in baby. PMID:27551179

  1. The pitfalls of bioterrorism preparedness: the anthrax and smallpox experiences.

    PubMed

    Cohen, Hillel W; Gould, Robert M; Sidel, Victor W

    2004-10-01

    Bioterrorism preparedness programs have contributed to death, illness, and waste of public health resources without evidence of benefit. Several deaths and many serious illnesses have resulted from the smallpox vaccination program; yet there is no clear evidence that a threat of smallpox exposure ever existed. The anthrax spores released in 2001 have been linked to secret US military laboratories-the resultant illnesses and deaths might not have occurred if those laboratories were not in operation. The present expansion of bioterrorism preparedness programs will continue to squander health resources, increase the dangers of accidental or purposeful release of dangerous pathogens, and further undermine efforts to enforce international treaties to ban biological and chemical weapons. The public health community should acknowledge the substantial harm that bioterrorism preparedness has already caused and develop mechanisms to increase our public health resources and to allocate them to address the world's real health needs. PMID:15451727

  2. Cutaneous Anthrax on Eyelid in a Pregnant Woman.

    PubMed

    Parlak, Emine; Erturk, Ayse; Erol, Serpil; Parlak, Mehmet; Ozkurt, Zulal

    2016-06-01

    A 32-year-old patient who was 17 weeks of pregnant referred to our hospital due to a lesion on the eyelid and swelling on her face. Patient's history revealed that she helped her husband for slaughtering of a sick animal and contacted with the meat. A scabby lesion was detected on the inferior eyelid with hyperaemia around, central necrotic appearance and swelling. The diagnosis of anthrax was performed based on her epidemiological data, physical examination findings, and Bacillus anthracis were seen on direct preparation. This case was considered worthy to present since she was pregnant, the disease was located on the inferior eyelid, which is a rare place for location, and caused no complication or sequel either in mother or in baby. PMID:27551179

  3. In silico design of smart binders to anthrax PA

    NASA Astrophysics Data System (ADS)

    Sellers, Michael; Hurley, Margaret M.

    2012-06-01

    The development of smart peptide binders requires an understanding of the fundamental mechanisms of recognition which has remained an elusive grail of the research community for decades. Recent advances in automated discovery and synthetic library science provide a wealth of information to probe fundamental details of binding and facilitate the development of improved models for a priori prediction of affinity and specificity. Here we present the modeling portion of an iterative experimental/computational study to produce high affinity peptide binders to the Protective Antigen (PA) of Bacillus anthracis. The result is a general usage, HPC-oriented, python-based toolkit based upon powerful third-party freeware, which is designed to provide a better understanding of peptide-protein interactions and ultimately predict and measure new smart peptide binder candidates. We present an improved simulation protocol with flexible peptide docking to the Anthrax Protective Antigen, reported within the context of experimental data presented in a companion work.

  4. Preparation and characterization of cobalt-substituted anthrax lethal factor

    SciTech Connect

    Saebel, Crystal E.; Carbone, Ryan; Dabous, John R.; Lo, Suet Y.; Siemann, Stefan

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer Cobalt-substituted anthrax lethal factor (CoLF) is highly active. Black-Right-Pointing-Pointer CoLF can be prepared by bio-assimilation and direct exchange. Black-Right-Pointing-Pointer Lethal factor binds cobalt tightly. Black-Right-Pointing-Pointer The electronic spectrum of CoLF reveals penta-coordination. Black-Right-Pointing-Pointer Interaction of CoLF with thioglycolic acid follows a 2-step mechanism. -- Abstract: Anthrax lethal factor (LF) is a zinc-dependent endopeptidase involved in the cleavage of mitogen-activated protein kinase kinases near their N-termini. The current report concerns the preparation of cobalt-substituted LF (CoLF) and its characterization by electronic spectroscopy. Two strategies to produce CoLF were explored, including (i) a bio-assimilation approach involving the cultivation of LF-expressing Bacillus megaterium cells in the presence of CoCl{sub 2}, and (ii) direct exchange by treatment of zinc-LF with CoCl{sub 2}. Independent of the method employed, the protein was found to contain one Co{sup 2+} per LF molecule, and was shown to be twice as active as its native zinc counterpart. The electronic spectrum of CoLF suggests the Co{sup 2+} ion to be five-coordinate, an observation similar to that reported for other Co{sup 2+}-substituted gluzincins, but distinct from that documented for the crystal structure of native LF. Furthermore, spectroscopic studies following the exposure of CoLF to thioglycolic acid (TGA) revealed a sequential mechanism of metal removal from LF, which likely involves the formation of an enzyme: Co{sup 2+}:TGA ternary complex prior to demetallation of the active site. CoLF reported herein constitutes the first spectroscopic probe of LF's active site, which may be utilized in future studies to gain further insight into the enzyme's mechanism and inhibitor interactions.

  5. Proton nuclear magnetic resonance studies on brain edema

    SciTech Connect

    Naruse, S.; Horikawa, Y.; Tanaka, C.; Hirakawa, K.; Nishikawa, H.; Yoshizaki, K.

    1982-06-01

    The water in normal and edematous brain tissues of rats was studied by the pulse nuclear magnetic resonance (NMR) technique, measuring the longitudinal relaxation time (T1) and the transverse relaxation time (T2). In the normal brain, T1 and T2 were single components, both shorter than in pure water. Prolongation and separation of T2 into two components, one fast and one slow, were the characteristic findings in brain edema induced by both cold injury and triethyl tin (TET), although some differences between the two types of edema existed in the content of the lesion and in the degree of changes in T1 and T2 values. Quantitative analysis of T1 and T2 values in their time course relating to water content demonstrated that prolongation of T1 referred to the volume of increased water in tissues examined, and that two phases of T2 reflected the distribution and the content of the edema fluid. From the analysis of the slow component of T2 versus water content during edema formation, it was demonstrated that the increase in edema fluid was steady, and its content was constant during formation of TET-induced edema. On the contrary, during the formation of cold-injury edema, water-rich edema fluid increased during the initial few hours, and protein-rich edema fluid increased thereafter. It was concluded that proton NMR relaxation time measurements may provide new understanding in the field of brain edema research.

  6. CYANOBACTERIA AND THEIR TOXINS.

    EPA Science Inventory

    Science Questions

    Harmful algal blooms (HAB) of cyanobacteria, also known as blue-green algae, have recently become more spatially and temporally prevalent in the US and worldwide. Cyanobacteria and their highly potent toxins are a significant hazard for human health and ...

  7. CYANOBACTERIA AND THEIR TOXINS

    EPA Science Inventory

    Science Questions

    Harmful algal blooms (HAB) of cyanobacteria, also known as blue-green algae, have recently become more spatially and temporally prevalent in the US and worldwide. Cyanobacteria and their highly potent toxins are a significant hazard for human health and ...

  8. Monitoring Method of Cow Anthrax Based on Gis and Spatial Statistical Analysis

    NASA Astrophysics Data System (ADS)

    Li, Lin; Yang, Yong; Wang, Hongbin; Dong, Jing; Zhao, Yujun; He, Jianbin; Fan, Honggang

    Geographic information system (GIS) is a computer application system, which possesses the ability of manipulating spatial information and has been used in many fields related with the spatial information management. Many methods and models have been established for analyzing animal diseases distribution models and temporal-spatial transmission models. Great benefits have been gained from the application of GIS in animal disease epidemiology. GIS is now a very important tool in animal disease epidemiological research. Spatial analysis function of GIS can be widened and strengthened by using spatial statistical analysis, allowing for the deeper exploration, analysis, manipulation and interpretation of spatial pattern and spatial correlation of the animal disease. In this paper, we analyzed the cow anthrax spatial distribution characteristics in the target district A (due to the secret of epidemic data we call it district A) based on the established GIS of the cow anthrax in this district in combination of spatial statistical analysis and GIS. The Cow anthrax is biogeochemical disease, and its geographical distribution is related closely to the environmental factors of habitats and has some spatial characteristics, and therefore the correct analysis of the spatial distribution of anthrax cow for monitoring and the prevention and control of anthrax has a very important role. However, the application of classic statistical methods in some areas is very difficult because of the pastoral nomadic context. The high mobility of livestock and the lack of enough suitable sampling for the some of the difficulties in monitoring currently make it nearly impossible to apply rigorous random sampling methods. It is thus necessary to develop an alternative sampling method, which could overcome the lack of sampling and meet the requirements for randomness. The GIS computer application software ArcGIS9.1 was used to overcome the lack of data of sampling sites.Using ArcGIS 9.1 and GEODA

  9. Toxin-induced respiratory distress.

    PubMed

    McKay, Charles A

    2014-02-01

    This article describes the impact of various toxic substances on the airway and pulmonary system. Pulmonary anatomy and physiology provide the basis for understanding the response to toxin-induced injury. Simple asphyxiants displace oxygen from the inspired air. Respiratory irritants include water-soluble and water-insoluble compounds. Several inhaled agents produce direct airway injury, which may be mediated by caustic, thermal, and hydrocarbon exposures. Unique pulmonary toxins and toxicants are discussed, as well as inhaled toxin mixtures. Several inhaled toxins may also impair oxygen transport. The pulmonary system may also provide a mechanism for systemic toxin delivery on respiratory exposure. PMID:24275172

  10. [Protein toxins of Staphylococcus aureus].

    PubMed

    Shamsutdinov, A F; Tiurin, Iu A

    2014-01-01

    Main scientific-research studies regarding protein bacterial toxins of the most widespread bacteria that belong to Staphylococcus spp. genus and in particular the most pathogenic species for humans--Staphylococcus aureus, are analyzed. Structural and biological properties of protein toxins that have received the name of staphylococcus pyrogenic toxins (PTSAg) are presented. Data regarding genetic regulation of secretion and synthesis of these toxins and 3 main regulatory genetic systems (agr--accessory gene regulator, xpr--extracellular protein regulator, sar--staphylococcal accessory regulator) that coordinate synthesis of the most important protein toxins and enzymes for virulence of S. aureus, are presented. PMID:25051707

  11. The Effect of Complete Decongestive Therapy on Edema Volume Reduction and Pain in Women With Post Breast Surgery Lymph Edema

    PubMed Central

    Angooti Oshnari, Leila; Hosseini, Seyed Ali; Haghighat, Shahpar; Hossein Zadeh, Samaneh

    2016-01-01

    Background Upper extremity lymph edema is the most common side effect of breast cancer treatment that may produce significant physical and psychological morbidity. Pain is the frequent symptom of lymph edema that causes impairment of activities in daily life. Objectives The aim of this study was assessment of the effect of complex decongestive therapy (CDT) on upper extremity lymph edema and pain in women with post breast surgery lymph edema. Patients and Methods In this quasi- experimental research with before- after design, 36 women with moderate lymph edema after breast surgery participated in the program. Edema volume was measured by water displacement method; pain values were evaluated by visual analog scale (VAS). Data were recorded before intervention and 2 and 4 weeks after it. CDT included the first phase (intensive phase) and the second phase (maintenance phase). Each phase lasted 2 weeks. After use of Shapiro Wilk test for normality, analysis of variances with GEE and repeated measurements were used to analyze the data. Results After one month doing CDT program, significant decrease of edema was noticed (P < 0.0001), also pain decreased during 2 and 4 weeks after intervention (P < 0.0001). Conclusions This study indicated that CDT program is effective in reducing lymph edema volume and pain in women with moderate post breast surgery lymph edema. It seems that raising patients’ awareness and training healthcare professionals regarding lymph edema preventive strategies have an important role in earlier and better combating this complication. PMID:27482330

  12. [Cardiogenic and non cardiogenic pulmonary edema: pathomechanisms and causes].

    PubMed

    Glaus, T; Schellenberg, S; Lang, J

    2010-07-01

    The development of pulmonary edema is divided in cardiogenic and non-cardiogenic. Cardiogenic edema pathogenically is caused by elevated hydrostatic pressure in the pulmonary capillaries due to left sided congestive heart failure. Non-cardiogenic pulmonary edema is categorized depending on the underlying pathogenesis in low-alveolar pressure, elevated permeability or neurogenic edema. Some important examples of causes are upper airway obstruction like in laryngeal paralysis or strangulation for low alveolar pressure, leptospirosis and ARDS for elevated permeability, and epilepsy, brain trauma and electrocution for neurogenic edema. The differentiation between cardiogenic versus non-cardiogenic genesis is not always straightforward, but most relevant, because treatment markedly differs between the two. Of further importance is the identification of the specific underlying cause in non-cardiogenic edema, not only for therapeutic but particularly for prognostic reasons. Depending on the cause the prognosis ranges from very poor to good chance of complete recovery. PMID:20582896

  13. Diffusion tensor-based tumor infiltration index cannot discriminate vasogenic edema from tumor-infiltrated edema.

    PubMed

    Kinoshita, Manabu; Goto, Tetsu; Okita, Yoshiko; Kagawa, Naoki; Kishima, Haruhiko; Hashimoto, Naoya; Yoshimine, Toshiki

    2010-02-01

    Diffusion tensor imaging (DTI) by magnetic resonance imaging (MRI) is now used not only for delineating white matter fiber tracts, but also for assessing the histological characteristics of pathological tissues. Among these uses, predicting the extent or existence of tumor cell invasion into white matter by DTI is under extensive investigation. The previously reported tumor infiltration index (TII) holds great potential for the discrimination of pure vasogenic edema from tumor-infiltrated edema. However, conflicting data are being reported questioning the clinical value of TII. The present investigation reevaluated the utility of TII in patients with meningioma or glioma. We found that TII was unable to discriminate vasogenic from tumor-infiltrated edema. Conversely, detailed voxel-by-voxel comparison of TII and (11)C-methionie PET in the T2-hyperintense area of gliomas showed that TII and (11)C-methionie PET has a positive correlation, suggesting that, although TII is unable to discriminate the cause of edema, the extent of tumor cell invasion into white matter is depicted in gliomas by TII. These data suggest that TII involves both vasogenic and tumor-infiltrated factors, rather than only a single factor. A more intensive investigation is required to reach a complete understanding of TII. PMID:19696968

  14. Monte Carlo N-particle simulation of neutron-based sterilisation of anthrax contamination

    PubMed Central

    Liu, B; Xu, J; Liu, T; Ouyang, X

    2012-01-01

    Objective To simulate the neutron-based sterilisation of anthrax contamination by Monte Carlo N-particle (MCNP) 4C code. Methods Neutrons are elementary particles that have no charge. They are 20 times more effective than electrons or γ-rays in killing anthrax spores on surfaces and inside closed containers. Neutrons emitted from a 252Cf neutron source are in the 100 keV to 2 MeV energy range. A 2.5 MeV D–D neutron generator can create neutrons at up to 1013 n s−1 with current technology. All these enable an effective and low-cost method of killing anthrax spores. Results There is no effect on neutron energy deposition on the anthrax sample when using a reflector that is thicker than its saturation thickness. Among all three reflecting materials tested in the MCNP simulation, paraffin is the best because it has the thinnest saturation thickness and is easy to machine. The MCNP radiation dose and fluence simulation calculation also showed that the MCNP-simulated neutron fluence that is needed to kill the anthrax spores agrees with previous analytical estimations very well. Conclusion The MCNP simulation indicates that a 10 min neutron irradiation from a 0.5 g 252Cf neutron source or a 1 min neutron irradiation from a 2.5 MeV D–D neutron generator may kill all anthrax spores in a sample. This is a promising result because a 2.5 MeV D–D neutron generator output >1013 n s−1 should be attainable in the near future. This indicates that we could use a D–D neutron generator to sterilise anthrax contamination within several seconds. PMID:22573293

  15. New Compton densitometer for measuring pulmonary edema

    SciTech Connect

    Loo, B.W.; Goulding, F.S.; Simon, D.S.

    1985-10-01

    Pulmonary edema is the pathological increase of extravascular lung water found most often in patients with congestive heart failure and other critically ill patients who suffer from intravenous fluid overload. A non-invasive lung density monitor that is accurate, easily portable, safe and inexpensive is needed for clinical evaluation of pulmonary edema. Other researchers who have employed Compton scattering techniques generally used systems of extended size and detectors with poor energy resolution. This has resulted in significant systematic biases from multiply-scattered photons and larger errors in counting statistics at a given radiation dose to the patient. We are proposing a patented approach in which only backscattered photons are measured with a high-resolution HPGe detector in a compact system geometry. By proper design and a unique data extraction scheme, effects of the variable chest wall on lung density measurements are minimized. Preliminary test results indicate that with a radioactive source of under 30 GBq, it should be possible to make an accurate lung density measurement in one minute, with a risk of radiation exposure to the patient a thousand times smaller than that from a typical chest x-ray. The ability to make safe, frequent lung density measurements could be very helpful for monitoring the course of P.E. at the hospital bedside or outpatient clinics, and for evaluating the efficacy of therapy in clinical research. 6 refs., 5 figs.

  16. The Curious Question of Exercise-Induced Pulmonary Edema

    PubMed Central

    Bates, Melissa L.; Farrell, Emily T.; Eldridge, Marlowe W.

    2011-01-01

    The question of whether pulmonary edema develops during exercise on land is controversial. Yet, the development of pulmonary edema during swimming and diving is well established. This paper addresses the current controversies that exist in the field of exercise-induced pulmonary edema on land and with water immersion. It also discusses the mechanisms by which pulmonary edema can develop during land exercise, swimming, and diving and the current gaps in knowledge that exist. Finally, this paper discusses how these fields can continue to advance and the areas where clinical knowledge is lacking. PMID:21660232

  17. Lung Epithelial Injury by B. Anthracis Lethal Toxin Is Caused by MKK-Dependent Loss of Cytoskeletal Integrity

    PubMed Central

    Lehmann, Mandy; Noack, Deborah; Wood, Malcolm; Perego, Marta; Knaus, Ulla G.

    2009-01-01

    Bacillus anthracis lethal toxin (LT) is a key virulence factor of anthrax and contributes significantly to the in vivo pathology. The enzymatically active component is a Zn2+-dependent metalloprotease that cleaves most isoforms of mitogen-activated protein kinase kinases (MKKs). Using ex vivo differentiated human lung epithelium we report that LT destroys lung epithelial barrier function and wound healing responses by immobilizing the actin and microtubule network. Long-term exposure to the toxin generated a unique cellular phenotype characterized by increased actin filament assembly, microtubule stabilization, and changes in junction complexes and focal adhesions. LT-exposed cells displayed randomly oriented, highly dynamic protrusions, polarization defects and impaired cell migration. Reconstitution of MAPK pathways revealed that this LT-induced phenotype was primarily dependent on the coordinated loss of MKK1 and MKK2 signaling. Thus, MKKs control fundamental aspects of cytoskeletal dynamics and cell motility. Even though LT disabled repair mechanisms, agents such as keratinocyte growth factor or dexamethasone improved epithelial barrier integrity by reducing cell death. These results suggest that co-administration of anti-cytotoxic drugs may be of benefit when treating inhalational anthrax. PMID:19270742

  18. BclA and toxin antigens augment each other to protect NMRI mice from lethal Bacillus anthracis challenge.

    PubMed

    Köhler, Susanne M; Baillie, Les W; Beyer, Wolfgang

    2015-06-01

    While proving highly effective in controlling Anthrax in farm animals all over the world currently attenuated live anthrax vaccines employed in a veterinary context suffer from drawbacks such as residual virulence, short term protection, variation in quality and, most importantly, lack of efficacy if administered simultaneously with antibiotics. These limitations have stimulated the development of non-living component vaccines which induce a broad spectrum immune response capable of targeting both toxaemia (as in the case of PA based vaccines) and bacteraemia. To contribute to this several new approaches were tested in outbred NMRI mice for antibody titres and protectiveness. Plasmids encoding a recombinant toxin derived fusion peptide and a spore surface derived peptide were tested as DNA-vaccines in comparison to their protein counterparts utilising two adjuvant approaches and two DNA-vector backbones. The combination of two plasmids encoding LFD1PAD4-mIPS1 and TPA-BclAD1D3-LAMP1, when delivered by GeneGun, protected 90% of the animals against a lethal challenge with 25LD50 spores of the Ames strain of Bacillus anthracis. Single applications of either antigen component showed significantly lower protection rates, indicating the beneficial interaction between anti-spore and anti-toxin components for an acellular vaccine formulation. PMID:25917676

  19. Clinical Framework and Medical Countermeasure Use During an Anthrax Mass-Casualty Incident.

    PubMed

    Bower, William A; Hendricks, Katherine; Pillai, Satish; Guarnizo, Julie; Meaney-Delman, Dana

    2015-12-01

    In 2014, CDC published updated guidelines for the prevention and treatment of anthrax (Hendricks KA, Wright ME, Shadomy SV, et al. Centers for Disease Control and Prevention expert panel meetings on prevention and treatment of anthrax in adults. Emerg Infect Dis 2014;20[2]. Available at http://wwwnc.cdc.gov/eid/article/20/2/13-0687_article.htm). These guidelines provided recommended best practices for the diagnosis and treatment of persons with naturally occurring or bioterrorism-related anthrax in conventional medical settings. An aerosolized release of Bacillus anthracis spores over densely populated areas could become a mass-casualty incident. To prepare for this possibility, the U.S. government has stockpiled equipment and therapeutics (known as medical countermeasures [MCMs]) for anthrax prevention and treatment. However, previously developed, publicly available clinical recommendations have not addressed the use of MCMs or clinical management during an anthrax mass-casualty incident, when the number of patients is likely to exceed the ability of the health care infrastructure to provide conventional standards of care and supplies of MCMs might be inadequate to meet the demand required. To address this gap, in 2013, CDC conducted a series of systematic reviews of the scientific literature on anthrax to identify evidence that could help clinicians and public health authorities set guidelines for intravenous antimicrobial and antitoxin use, diagnosis of anthrax meningitis, and management of common anthrax-specific complications in the setting of a mass-casualty incident. Evidence from these reviews was presented to professionals with expertise in anthrax, critical care, and disaster medicine during a series of workgroup meetings that were held from August 2013 through March 2014. In March 2014, a meeting was held at which 102 subject matter experts discussed the evidence and adapted the existing best practices guidance to a clinical use framework for the

  20. Toxins and drug discovery.

    PubMed

    Harvey, Alan L

    2014-12-15

    Components from venoms have stimulated many drug discovery projects, with some notable successes. These are briefly reviewed, from captopril to ziconotide. However, there have been many more disappointments on the road from toxin discovery to approval of a new medicine. Drug discovery and development is an inherently risky business, and the main causes of failure during development programmes are outlined in order to highlight steps that might be taken to increase the chances of success with toxin-based drug discovery. These include having a clear focus on unmet therapeutic needs, concentrating on targets that are well-validated in terms of their relevance to the disease in question, making use of phenotypic screening rather than molecular-based assays, and working with development partners with the resources required for the long and expensive development process. PMID:25448391

  1. Evidence of Local Persistence of Human Anthrax in the Country of Georgia Associated with Environmental and Anthropogenic Factors

    PubMed Central

    Kracalik, Ian T.; Malania, Lile; Tsertsvadze, Nikoloz; Manvelyan, Julietta; Bakanidze, Lela; Imnadze, Paata; Tsanava, Shota; Blackburn, Jason K.

    2013-01-01

    Background Anthrax is a soil-borne disease caused by the bacterium Bacillus anthracis and is considered a neglected zoonosis. In the country of Georgia, recent reports have indicated an increase in the incidence of human anthrax. Identifying sub-national areas of increased risk may help direct appropriate public health control measures. The purpose of this study was to evaluate the spatial distribution of human anthrax and identify environmental/anthropogenic factors associated with persistent clusters. Methods/Findings A database of human cutaneous anthrax in Georgia during the period 2000–2009 was constructed using a geographic information system (GIS) with case data recorded to the community location. The spatial scan statistic was used to identify persistence of human cutaneous anthrax. Risk factors related to clusters of persistence were modeled using a multivariate logistic regression. Areas of persistence were identified in the southeastern part of the country. Results indicated that the persistence of human cutaneous anthrax showed a strong positive association with soil pH and urban areas. Conclusions/Significance Anthrax represents a persistent threat to public and veterinary health in Georgia. The findings here showed that the local level heterogeneity in the persistence of human cutaneous anthrax necessitates directed interventions to mitigate the disease. High risk areas identified in this study can be targeted for public health control measures such as farmer education and livestock vaccination campaigns. PMID:24040426

  2. The susceptibility of the mallard duck (Anas platyrhynchos) to Clostridium botulinum C2 toxin

    USGS Publications Warehouse

    Jensen, W.I.; Duncan, R.M.

    1980-01-01

    Most strains of Clostridium botulinum type C, after having lost their capacity to produce their dominant toxin (C1) as a result of being "cured" of their prophages, continue to produce C2, a trypsin-activable toxin reported by other investigators. While of relatively low toxicity when administered perorally to the adult mallard duck (Anas platyrhynchos), it was highly toxic when given parenterally. By the intravenous route, for example, it was more than 1,000 times as toxic as C1 toxin by the same route, when compared on the basis of mouse intraperitoneal toxicity. The cause of death in every instance was massive pulmonary edema and hemorrhage rather than the respiratory paralysis that occurs in C1 intoxication.

  3. Source and risk factors of a cutaneous anthrax outbreak, Jiangsu, Eastern China, 2012.

    PubMed

    Hu, J L; Cui, L L; Bao, C J; Tan, Z M; Rutherford, S; Ying, L; Zhang, M L; Zhu, F C

    2016-09-01

    Anthrax is still a severe public health problem and threat to human health. A cutaneous anthrax outbreak occurred in Jiangsu Province, a non-endemic anthrax region of eastern China, from July to August 2012. Epidemiological and laboratory investigation were initiated to trace the source of infection and identify the risk factors of the outbreak. On 25 July 2012, 17 persons were exposed to a sick cow, which had been imported from northeast China a few days previously. Of the 17 exposed, eight developed symptoms between 1 and 8 days and were diagnosed as cutaneous anthrax cases. Three main genes of Bacillus anthracis were detected from both human and cow meat samples, indicating that the outbreak was associated with this infected cow. A retrospective cohort study showed that contact with blood and presence of skin damage contributed to the case infection with B. anthracis. The outbreak highlights the need to enhance quarantine for imported livestock, which should have been vaccinated prior to importation, the significance of education for high-risk individuals, and training for primary healthcare workers even in anthrax-free areas. PMID:27277672

  4. Responding to the threat of bioterrorism: a microbial ecology perspective--the case of anthrax.

    PubMed

    Atlas, R M

    2002-12-01

    Anthrax is a disease of herbivores caused by the gram-positive bacterium Bacillus anthracis. It can affect cattle, sheep, swine, horses and various species of wildlife. The routes for the spread among wildlife are reviewed. There are three kinds of human anthrax--inhalation, cutaneous, and intestinal anthrax--which differ in their routes of infection and outcomes. In the United States, confirmation of cases is made by the isolation of B. anthracis and by biochemical tests. Vaccination is not recommended for the general public; civilians who should be vaccinated include those who, in their work places, come in contact with products potentially contaminated with B. anthracis spores, and people engaged in research or diagnostic activities. After September 11, 2001, there were bioterrorism anthrax attacks in the United States: anthrax-laced letters sent to multiple locations were the source of infectious B. anthracis. The US Postal Service issued recommendations to prevent the danger of hazardous exposure to the bacterium. B. anthracis spores can spread easily and persist for very long times, which makes decontamination of buildings very difficult. Early detection, rapid diagnosis, and well-coordinated public health response are the key to minimizing casualties. The US Government is seeking new ways to deter bioterrorism, including a tighter control of research on infectious agents, even though pathogens such as B. anthracis are widely spread in nature and easy to grow. It is necessary to define the boundary between defensive and offensive biological weapons research. Deterring bioterrorism should not restrict critical scientific research. PMID:12497181

  5. Characterization of F107 fimbriae of Escherichia coli 107/86, which causes edema disease in pigs, and nucleotide sequence of the F107 major fimbrial subunit gene, fedA.

    PubMed Central

    Imberechts, H; De Greve, H; Schlicker, C; Bouchet, H; Pohl, P; Charlier, G; Bertschinger, H; Wild, P; Vandekerckhove, J; Van Damme, J

    1992-01-01

    F107 fimbriae were isolated and purified from edema disease strain 107/86 of Escherichia coli. Plasmid pIH120 was constructed, which contains the gene cluster that codes for adhesive F107 fimbriae. The major fimbrial subunit gene, fedA, was sequenced. An open reading frame that codes for a protein with 170 amino acids, including a 21-amino-acid signal peptide, was found. The protein without the signal sequence has a calculated molecular mass of 15,099 Da. Construction of a nonsense mutation in the open reading frame of fedA abolished both fimbrial expression and the capacity to adhere to isolated porcine intestinal villi. In a screening of 28 reference edema disease strains and isolates from clinically ill piglets, fedA was detected in 24 cases (85.7%). In 20 (83.3%) of these 24 strains, fedA was found in association with Shiga-like toxin II variant genes, coding for the toxin that is characteristic for edema disease strains of E. coli. The fimbrial subunit gene was not detected in enterotoxigenic E. coli strains. Because of the capacity of E. coli HB101(pIH120) transformants to adhere to isolated porcine intestinal villi, the high prevalence of fedA in edema disease strains, and the high correlation with the Shiga-like toxin II variant toxin-encoding genes, we suggest that F107 fimbriae are an important virulence factor in edema disease strains of E. coli. Images PMID:1348723

  6. Acquired coagulant factor VIII deficiency induced by Bacillus anthracis lethal toxin in mice

    PubMed Central

    Sun, Der-Shan; Lee, Po-Chien; Kau, Jyh-Hwa; Shih, Yung-Luen; Huang, Hsin-Hsien; Li, Chen-Ru; Lee, Chin-Cheng; Wu, Yu-Ping; Chen, Kuo-Ching; Chang, Hsin-Hou

    2015-01-01

    Mice treated with anthrax lethal toxin (LT) exhibit hemorrhage caused by unknown mechanisms. Moreover, LT treatment in mice induced liver damage. In this study, we hypothesized that a suppressed coagulation function may be associated with liver damage, because the liver is the major producing source of coagulation factors. The hepatic expression of coagulant factors and the survival rates were analyzed after cultured cells or mice were exposed to LT. In agreement with our hypothesis, LT induces cytotoxicity against hepatic cells in vitro. In addition, suppressed expression of coagulation factor VIII (FVIII) in the liver is associated with a prolonged plasma clotting time in LT-treated mice, suggesting a suppressive role of LT in coagulation. Accordingly, we further hypothesized that a loss-of-function approach involving treatments of an anticoagulant should exacerbate LT-induced abnormalities, whereas a gain-of-function approach involving injections of recombinant FVIII to complement the coagulation deficiency should ameliorate the pathogenesis. As expected, a sublethal dose of LT caused mortality in the mice that were non-lethally pretreated with an anticoagulant (warfarin). By contrast, treatments of recombinant FVIII reduced the mortality from a lethal dose of LT in mice. Our results indicated that LT-induced deficiency of FVIII is involved in LT-mediated pathogenesis. Using recombinant FVIII to correct the coagulant defect may enable developing a new strategy to treat anthrax. PMID:25906166

  7. Acquired coagulant factor VIII deficiency induced by Bacillus anthracis lethal toxin in mice.

    PubMed

    Sun, Der-Shan; Lee, Po-Chien; Kau, Jyh-Hwa; Shih, Yung-Luen; Huang, Hsin-Hsien; Li, Chen-Ru; Lee, Chin-Cheng; Wu, Yu-Ping; Chen, Kuo-Ching; Chang, Hsin-Hou

    2015-01-01

    Mice treated with anthrax lethal toxin (LT) exhibit hemorrhage caused by unknown mechanisms. Moreover, LT treatment in mice induced liver damage. In this study, we hypothesized that a suppressed coagulation function may be associated with liver damage, because the liver is the major producing source of coagulation factors. The hepatic expression of coagulant factors and the survival rates were analyzed after cultured cells or mice were exposed to LT. In agreement with our hypothesis, LT induces cytotoxicity against hepatic cells in vitro. In addition, suppressed expression of coagulation factor VIII (FVIII) in the liver is associated with a prolonged plasma clotting time in LT-treated mice, suggesting a suppressive role of LT in coagulation. Accordingly, we further hypothesized that a loss-of-function approach involving treatments of an anticoagulant should exacerbate LT-induced abnormalities, whereas a gain-of-function approach involving injections of recombinant FVIII to complement the coagulation deficiency should ameliorate the pathogenesis. As expected, a sublethal dose of LT caused mortality in the mice that were non-lethally pretreated with an anticoagulant (warfarin). By contrast, treatments of recombinant FVIII reduced the mortality from a lethal dose of LT in mice. Our results indicated that LT-induced deficiency of FVIII is involved in LT-mediated pathogenesis. Using recombinant FVIII to correct the coagulant defect may enable developing a new strategy to treat anthrax. PMID:25906166

  8. Method for detecting biological toxins

    SciTech Connect

    Ligler, F.S.; Campbell, J.R.

    1992-01-01

    Biological toxins are indirectly detected by using polymerase chain reaction to amplify unique nucleic acid sequences coding for the toxins or enzymes unique to toxin synthesis. Buffer, primers coding for the unique nucleic acid sequences and an amplifying enzyme are added to a sample suspected of containing the toxin. The mixture is then cycled thermally to exponentially amplify any of these unique nucleic acid sequences present in the sample. The amplified sequences can be detected by various means, including fluorescence. Detection of the amplified sequences is indicative of the presence of toxin in the original sample. By using more than one set of labeled primers, the method can be used to simultaneously detect several toxins in a sample.

  9. Nonproliferative diabetic retinopathy and macular edema.

    PubMed

    Smith, S C

    1999-01-01

    As previously noted, although visual loss usually does not fall below 20/200 in the presence of ME, it may nevertheless be a significant disability. Additional interventions may include referral to low vision clinics, home health agencies, visual loss support groups, and local or regional blindness agencies to aid the patient's occupational rehabilitation, coping mechanisms, and adaptation responses in the presence of this potentially debilitating process. Control of blood sugar, blood pressure, and the intervention of focal/grid laser treatments to seal leaks and prevent further edema provide the best chance of maintaining useful vision throughout life. Patient education is paramount to improve comprehension of the condition, recommended treatment modalities, and compliance with prescribed regimens. Assessments and interventions related to knowledge and sensory deficits, anxiety, discomfort, ineffective coping mechanisms, and health maintenance behaviors add a quality link in the multidisciplinary approach surrounding the delivery of care to patients with NPDR and clinically significant ME. PMID:11907881

  10. Serotonin syndrome presenting as pulmonary edema

    PubMed Central

    Shah, Nilima Deepak; Jain, Ajay B.

    2016-01-01

    Serotonin syndrome (SS) is a potentially life-threatening condition resulting from excessive central and peripheral serotonergic activity. Clinically, it is a triad of mental-status changes, neuromuscular abnormalities, and autonomic disturbances. It can be caused by intentional self-poisoning, overdose, or inadvertent drug interactions. We report the case of a 58-year-old male with type 2 diabetes mellitus and obsessive compulsive disorder who developed pulmonary edema as a possible complication of SS. SS was caused by a combination of three specific serotonin re-uptake inhibitors (fluoxetine, fluvoxamine, and sertraline), linezolid, and fentanyl. The hospital course was further complicated by difficult weaning from the ventilator. SS was identified and successfully treated with cyproheptadine and lorazepam. The case highlights the importance of effective consultation-liaison and prompt recognition of SS as the presentation may be complex in the presence of co-morbid medical illness. PMID:26997733

  11. Serotonin syndrome presenting as pulmonary edema.

    PubMed

    Shah, Nilima Deepak; Jain, Ajay B

    2016-01-01

    Serotonin syndrome (SS) is a potentially life-threatening condition resulting from excessive central and peripheral serotonergic activity. Clinically, it is a triad of mental-status changes, neuromuscular abnormalities, and autonomic disturbances. It can be caused by intentional self-poisoning, overdose, or inadvertent drug interactions. We report the case of a 58-year-old male with type 2 diabetes mellitus and obsessive compulsive disorder who developed pulmonary edema as a possible complication of SS. SS was caused by a combination of three specific serotonin re-uptake inhibitors (fluoxetine, fluvoxamine, and sertraline), linezolid, and fentanyl. The hospital course was further complicated by difficult weaning from the ventilator. SS was identified and successfully treated with cyproheptadine and lorazepam. The case highlights the importance of effective consultation-liaison and prompt recognition of SS as the presentation may be complex in the presence of co-morbid medical illness. PMID:26997733

  12. Oxygen-deficient metabolism and corneal edema

    PubMed Central

    Leung, B.K.; Bonanno, J.A.; Radke, C.J.

    2014-01-01

    Wear of low-oxygen-transmissible soft contact lenses swells the cornea significantly, even during open eye. Although oxygen-deficient corneal edema is well-documented, a self-consistent quantitative prediction based on the underlying metabolic reactions is not available. We present a biochemical description of the human cornea that quantifies hypoxic swelling through the coupled transport of water, salt, and respiratory metabolites. Aerobic and anaerobic consumption of glucose, as well as acidosis and pH buffering, are incorporated in a seven-layer corneal model (anterior chamber, endothelium, stroma, epithelium, postlens tear film, contact lens, and prelens tear film). Corneal swelling is predicted from coupled transport of water, dissolved salts, and especially metabolites, along with membrane-transport resistances at the endothelium and epithelium. At the endothelium, the Na+/K+ - ATPase electrogenic channel actively transports bicarbonate ion from the stroma into the anterior chamber. As captured by the Kedem–Katchalsky membrane-transport formalism, the active bicarbonate-ion flux provides the driving force for corneal fluid pump-out needed to match the leak-in tendency of the stroma. Increased lactate-ion production during hypoxia osmotically lowers the pump-out rate requiring the stroma to swell to higher water content. Concentration profiles are predicted for glucose, water, oxygen, carbon dioxide, and hydronium, lactate, bicarbonate, sodium, and chloride ions, along with electrostatic potential and pressure profiles. Although the active bicarbonate-ion pump at the endothelium drives bicarbonate into the aqueous humor, we find a net flux of bicarbonate ion into the cornea that safeguards against acidosis. For the first time, we predict corneal swelling upon soft-contact-lens wear from fundamental biophysico-chemical principles. We also successfully predict that hypertonic tear alleviates contact-lens-induced edema. PMID:21820076

  13. Diabetic Macular Edema: Options for Adjunct Therapy.

    PubMed

    Calvo, Pilar; Abadia, Beatriz; Ferreras, Antonio; Ruiz-Moreno, Oscar; Verdes, Guayente; Pablo, Luis E

    2015-09-01

    Diabetes mellitus (DM) is a chronic disease that affects 387 million people worldwide. Diabetic retinopathy (DR), a common complication of DM, is the main cause of blindness in the active population. Diabetic macular edema (DME) may occur at any stage of DR, and is characterized by vascular hyperpermeability accompanied by hard exudates within the macula. Medical and surgical therapies have dramatically reduced the progression of DR, and timely intervention can reduce the risk of severe vision loss by more than 90 %. In 2012, intravitreal ranibizumab became the first antivascular endothelial growth factor (anti-VEGF) agent approved for DME and, since then, many reports of the use of ranibizumab for DME have been promising. Randomized, prospective, multicenter clinical trials-most notably, RESOLVE, READ-2, RISE/RIDE, RESTORE, DRCR.net protocol I, and RETAIN-reported improvements in best-corrected visual acuity and decreased central retinal thickness as measured with optical coherence tomography in patients with DME. Similar treatment benefits have also been noted in clinical trials evaluating intravitreal aflibercept and bevacizumab (DAVINCI, VISTA/VIVID, and BOLT) and more recently DRCR.net protocol T. Intravitreal steroids (dexamethasone intravitreal implant and fluocinolone acetonide), particularly in refractory cases, also play a significant role in the management of DME (MEAD/CHAMPLAIN and FAMOUS/FAME studies). In summary, over the last 5 years, blocking VEGF and inflammation has been shown to improve visual outcomes in patients with macular edema due to DM, revolutionizing the treatment of center-involved DME and establishing a new standard of care. PMID:26242766

  14. Oxygen-deficient metabolism and corneal edema.

    PubMed

    Leung, B K; Bonanno, J A; Radke, C J

    2011-11-01

    Wear of low-oxygen-transmissible soft contact lenses swells the cornea significantly, even during open eye. Although oxygen-deficient corneal edema is well-documented, a self-consistent quantitative prediction based on the underlying metabolic reactions is not available. We present a biochemical description of the human cornea that quantifies hypoxic swelling through the coupled transport of water, salt, and respiratory metabolites. Aerobic and anaerobic consumption of glucose, as well as acidosis and pH buffering, are incorporated in a seven-layer corneal model (anterior chamber, endothelium, stroma, epithelium, postlens tear film, contact lens, and prelens tear film). Corneal swelling is predicted from coupled transport of water, dissolved salts, and especially metabolites, along with membrane-transport resistances at the endothelium and epithelium. At the endothelium, the Na+/K+ - ATPase electrogenic channel actively transports bicarbonate ion from the stroma into the anterior chamber. As captured by the Kedem-Katchalsky membrane-transport formalism, the active bicarbonate-ion flux provides the driving force for corneal fluid pump-out needed to match the leak-in tendency of the stroma. Increased lactate-ion production during hypoxia osmotically lowers the pump-out rate requiring the stroma to swell to higher water content. Concentration profiles are predicted for glucose, water, oxygen, carbon dioxide, and hydronium, lactate, bicarbonate, sodium, and chloride ions, along with electrostatic potential and pressure profiles. Although the active bicarbonate-ion pump at the endothelium drives bicarbonate into the aqueous humor, we find a net flux of bicarbonate ion into the cornea that safeguards against acidosis. For the first time, we predict corneal swelling upon soft-contact-lens wear from fundamental biophysico-chemical principles. We also successfully predict that hypertonic tear alleviates contact-lens-induced edema. PMID:21820076

  15. Recombinant Toxins for Cancer Treatment

    NASA Astrophysics Data System (ADS)

    Pastan, Ira; Fitzgerald, David

    1991-11-01

    Recombinant toxins target cell surface receptors and antigens on tumor cells. They kill by mechanisms different from conventional chemotherapy, so that cross resistance to conventional chemotherapeutic agents should not be a problem. Furthermore, they are not mutagens and should not induce secondary malignancies or accelerate progression of benign malignancies. They can be mass-produced cheaply in bacteria as homogeneous proteins. Either growth factor-toxin fusions or antibody-toxin fusions can be chosen, depending on the cellular target.

  16. Toxin Plasmids of Clostridium perfringens

    PubMed Central

    Li, Jihong; Adams, Vicki; Bannam, Trudi L.; Miyamoto, Kazuaki; Garcia, Jorge P.; Uzal, Francisco A.; Rood, Julian I.

    2013-01-01

    SUMMARY In both humans and animals, Clostridium perfringens is an important cause of histotoxic infections and diseases originating in the intestines, such as enteritis and enterotoxemia. The virulence of this Gram-positive, anaerobic bacterium is heavily dependent upon its prolific toxin-producing ability. Many of the ∼16 toxins produced by C. perfringens are encoded by large plasmids that range in size from ∼45 kb to ∼140 kb. These plasmid-encoded toxins are often closely associated with mobile elements. A C. perfringens strain can carry up to three different toxin plasmids, with a single plasmid carrying up to three distinct toxin genes. Molecular Koch's postulate analyses have established the importance of several plasmid-encoded toxins when C. perfringens disease strains cause enteritis or enterotoxemias. Many toxin plasmids are closely related, suggesting a common evolutionary origin. In particular, most toxin plasmids and some antibiotic resistance plasmids of C. perfringens share an ∼35-kb region containing a Tn916-related conjugation locus named tcp (transfer of clostridial plasmids). This tcp locus can mediate highly efficient conjugative transfer of these toxin or resistance plasmids. For example, conjugative transfer of a toxin plasmid from an infecting strain to C. perfringens normal intestinal flora strains may help to amplify and prolong an infection. Therefore, the presence of toxin genes on conjugative plasmids, particularly in association with insertion sequences that may mobilize these toxin genes, likely provides C. perfringens with considerable virulence plasticity and adaptability when it causes diseases originating in the gastrointestinal tract. PMID:23699255

  17. Ricin detection: tracking active toxin.

    PubMed

    Bozza, William P; Tolleson, William H; Rosado, Leslie A Rivera; Zhang, Baolin

    2015-01-01

    Ricin is a plant toxin with high bioterrorism potential due to its natural abundance and potency in inducing cell death. Early detection of the active toxin is essential for developing appropriate countermeasures. Here we review concepts for designing ricin detection methods, including mechanism of action of the toxin, advantages and disadvantages of current detection assays, and perspectives on the future development of rapid and reliable methods for detecting ricin in environmental samples. PMID:25481398

  18. Massive vulvar edema in 2 prepartum dairy cows

    PubMed Central

    Cheong, Soon Hon; Gilbert, Robert O.

    2014-01-01

    Two late gestation Holstein cows about to begin the third lactation developed massive vulvar edema. These were the only affected animals in the herd of 500 milking cows. The vulvar edema spontaneously regressed postpartum for both cows. Massive vulvar swelling is seldom observed in dairy cows in advanced pregnancy and is not described in the literature. PMID:24790232

  19. Lung Edema Clearance: Relevance to Patients with Lung Injury

    PubMed Central

    Azzam, Zaher S.; Sznajder, Jacob I.

    2015-01-01

    Pulmonary edema clearance is necessary for patients with lung injury to recover and survive. The mechanisms regulating edema clearance from the lungs are distinct from the factors contributing edema formation during injury. Edema clearance is effected via vectorial transport of Na+ out of the airspaces which generates an osmotic gradient causing water to follow the gradient out of the cells. This Na+ transport across the alveolar epithelium is mostly effected via apical Na+ and chloride channels and basolateral Na,K-ATPase. The Na,K-ATPase pumps Na+ out of the cell and K+ into the cell against their respective gradients in an ATP-consuming reaction. Two mechanisms contribute to the regulation of the Na,K-ATPase activity:recruitment of its subunits from intracellular compartments into the basolateral membrane, and transcriptional/translational regulation. Na,K-ATPase activity and edema clearance are increased by catecholamines, aldosterone, vasopressin, overexpression of the pump genes, and others. During lung injury, mechanisms regulating edema clearance are inhibited by yet unclear pathways. Better understanding of the mechanisms that regulate pulmonary edema clearance may lead to therapeutic interventions that counterbalance the inhibition of edema clearance during lung injury and improve the lungs’ ability to clear fluid, which is crucial for patient survival. PMID:26241220

  20. Disease-enhancing antibodies improve the efficacy of bacterial toxin-neutralizing antibodies

    PubMed Central

    Chow, Siu-Kei; Smith, Cameron; MacCarthy, Thomas; Pohl, Mary Ann; Bergman, Aviv; Casadevall, Arturo

    2013-01-01

    SUMMARY During infection, humoral immunity produces a polyclonal response with various immunoglobulins recognizing different epitopes within the microbe or toxin. Despite this diverse response, the biological activity of an antibody (Ab) is usually assessed by the action of a monoclonal population. We demonstrate that a combination of monoclonal antibodies (mAbs) that are individually disease-enhancing or neutralizing to Bacillus anthracis protective antigen (PA), a component of anthrax toxin, results in significantly augmented protection against the toxin. This boosted protection is Fc gamma receptor (FcγR)-dependent and involves the formation of stoichiometrically defined mAb-PA complexes that requires immunoglobulin bivalence and simultaneous interaction between PA and the two mAbs. The formation of these mAb-PA complexes inhibits PA oligomerization, resulting in protection. These data suggest that functional assessments of single Abs may inaccurately predict how the same Abs will operate in polyclonal preparations and imply that potentially therapeutic mAbs may be overlooked in single Ab screens. PMID:23601104