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David Deshazer - One of the best experts on this subject based on the ideXlab platform.

  • DBSecSys: a database of Burkholderia mallei secretion systems
    BMC Bioinformatics, 2014
    Co-Authors: Vesna Memišević, Kamal Kumar, Li Cheng, Nela Zavaljevski, David Deshazer, Anders Wallqvist, Jaques Reifman
    Abstract:

    Background Bacterial pathogenicity represents a major public health concern worldwide. Secretion systems are a key component of bacterial pathogenicity, as they provide the means for bacterial proteins to penetrate host-cell membranes and insert themselves directly into the host cells’ cytosol. Burkholderia mallei is a Gram-negative bacterium that uses multiple secretion systems during its host infection life cycle. To date, the identities of secretion system proteins for B. mallei are not well known, and their pathogenic mechanisms of action and host factors are largely uncharacterized.

  • distinct human antibody response to the biological warfare agent Burkholderia mallei
    Virulence, 2012
    Co-Authors: John J Varga, David Deshazer, David M Waag, Adam Vigil, Philip L Felgner, Joanna B Goldberg
    Abstract:

    The genetic similarity between Burkholderia mallei (glanders) and Burkholderia pseudomallei (melioidosis) had led to the general assumption that pathogenesis of each bacterium would be similar. In 2000, the first human case of glanders in North America since 1945 was reported in a microbiology laboratory worker. Leveraging the availability of pre-exposure sera for this individual and employing the same well-characterized protein array platform that has been previously used to study a large cohort of melioidosis patients in southeast Asia, we describe the antibody response in a human with glanders. Analysis of 156 peptides present on the array revealed antibodies against 17 peptides with a > 2-fold increase in this infection. Unexpectedly, when the glanders data were compared with a previous data set from B. pseudomallei infections, there were only two highly increased antibodies shared between these two infections. These findings have implications in the diagnosis and treatment of B. mallei and B. pseudomallei infections.

  • molecular insights into Burkholderia pseudomallei and Burkholderia mallei pathogenesis
    Annual Review of Microbiology, 2010
    Co-Authors: Edouard E Galyov, Paul J Brett, David Deshazer
    Abstract:

    Burkholderia pseudomallei and Burkholderia mallei are closely related gram-negative bacteria that can cause serious diseases in humans and animals. This review summarizes the current and rapidly expanding knowledge on the specific virulence factors employed by these pathogens and their roles in the pathogenesis of melioidosis and glanders. In particular, the contributions of recently identified virulence factors are described in the context of the intracellular lifestyle of these pathogens. Throughout this review, unique and shared virulence features of B. pseudomallei and B. mallei are discussed.

  • continuing evolution of Burkholderia mallei through genome reduction and large scale rearrangements
    Genome Biology and Evolution, 2010
    Co-Authors: Donald E Woods, David Deshazer, Catherine M Ronning, Lauren M Brinkac, Talima Pearson, Liliana Losada, Natalie D Fedorova, Svetlana A Shabalina, Tannistha Nandi
    Abstract:

    Burkholderia mallei (Bm), the causative agent of the predominately equine disease glanders, is a genetically uniform species that is very closely related to the much more diverse species Burkholderia pseudomallei (Bp), an opportunistic human pathogen and the primary cause of melioidosis. To gain insight into the relative lack of genetic diversity within Bm, we performed whole-genome comparative analysis of seven Bm strains and contrasted these with eight Bp strains. The Bm core genome (shared by all seven strains) is smaller in size than that of Bp, but the inverse is true for the variable gene sets that are distributed across strains. Interestingly, the biological roles of the Bm variable gene sets are much more homogeneous than those of Bp. The Bm variable genes are found mostly in contiguous regions flanked by insertion sequence (IS) elements, which appear to mediate excision and subsequent elimination of groups of genes that are under reduced selection in the mammalian host. The analysis suggests that the Bm genome continues to evolve through random IS-mediated recombination events, and differences in gene content may contribute to differences in virulence observed among Bm strains. The results are consistent with the view that Bm recently evolved from a single strain of Bp upon introduction into an animal host followed by expansion of IS elements, prophage elimination, and genome rearrangements and reduction mediated by homologous recombination across IS elements.

  • type vi secretion is a major virulence determinant in Burkholderia mallei
    Molecular Microbiology, 2007
    Co-Authors: Mark A Schell, William C Nierman, Ricky L Ulrich, Wilson J Ribot, Ernst E Brueggemann, Harry B Hines, Dan Chen, Lyla Lipscomb, Jan Mrazek, David Deshazer
    Abstract:

    Abstract : Burkholderia mallei is a host-adapted pathogen and a category B biothreat agent. Although the B. mallei VirAG two-component regulatory system is required for virulence in hamsters, the virulence genes it regulates are unknown. Here we show with expression profiling that overexpression of virAG resulted in transcriptional activation of approximately 60 genes, including some involved in capsule production, actin-based intracellular motility, and type VI secretion (T6S). The 15 genes encoding the major sugar component of the homopolymeric capsule were up-expressed > 2.5-fold, but capsule was still produced in the absence of virAG. Actin tail formation required virAG as well as bimB, bimC and bimE, three previously uncharacterized genes that were activated four- to 15-fold when VirAG was overproduced. Surprisingly, actin polymerization was found to be dispensable for virulence in hamsters. In contrast, genes encoding a T6S system were up-expressed as much as 30-fold and mutations in this T6S gene cluster resulted in strains that were avirulent in hamsters. SDS-PAGE and mass spectrometry demonstrated that BMAA0742 was secreted by the T6S system when virAG was overexpressed. Purified His-tagged BMAA0742 was recognized by glanders antiserum from a horse, a human and mice, indicating that this Hcp-family protein is produced in vivo during infection.

Ricky L Ulrich - One of the best experts on this subject based on the ideXlab platform.

  • the Burkholderia mallei bmar3 bmai3 quorum sensing system produces and responds to n 3 hydroxy octanoyl homoserine lactone
    Journal of Bacteriology, 2008
    Co-Authors: Breck A Duerkop, Ricky L Ulrich, Jake P Herman, Mair E A Churchill, Peter E Greenberg
    Abstract:

    Burkholderia mallei has two acyl-homoserine lactone (acyl-HSL) signal generator-receptor pairs and two additional signal receptors, all of which contribute to virulence. We show that B. mallei produces N-3-hydroxy-octanoyl HSL (3OHC8-HSL) but a bmaI3 mutant does not. Recombinant Escherichia coli expressing BmaI3 produces hydroxylated acyl-HSLs, with 3OHC8-HSL being the most abundant compound. In recombinant E. coli, BmaR3 responds to 3OHC8-HSL but not to other acyl-HSLs. These data indicate that the signal for BmaR3-BmaI3 quorum sensing is 3OHC8-HSL.

  • type vi secretion is a major virulence determinant in Burkholderia mallei
    Molecular Microbiology, 2007
    Co-Authors: Mark A Schell, William C Nierman, Ricky L Ulrich, Wilson J Ribot, Ernst E Brueggemann, Harry B Hines, Dan Chen, Lyla Lipscomb, Jan Mrazek, David Deshazer
    Abstract:

    Abstract : Burkholderia mallei is a host-adapted pathogen and a category B biothreat agent. Although the B. mallei VirAG two-component regulatory system is required for virulence in hamsters, the virulence genes it regulates are unknown. Here we show with expression profiling that overexpression of virAG resulted in transcriptional activation of approximately 60 genes, including some involved in capsule production, actin-based intracellular motility, and type VI secretion (T6S). The 15 genes encoding the major sugar component of the homopolymeric capsule were up-expressed > 2.5-fold, but capsule was still produced in the absence of virAG. Actin tail formation required virAG as well as bimB, bimC and bimE, three previously uncharacterized genes that were activated four- to 15-fold when VirAG was overproduced. Surprisingly, actin polymerization was found to be dispensable for virulence in hamsters. In contrast, genes encoding a T6S system were up-expressed as much as 30-fold and mutations in this T6S gene cluster resulted in strains that were avirulent in hamsters. SDS-PAGE and mass spectrometry demonstrated that BMAA0742 was secreted by the T6S system when virAG was overexpressed. Purified His-tagged BMAA0742 was recognized by glanders antiserum from a horse, a human and mice, indicating that this Hcp-family protein is produced in vivo during infection.

  • the animal pathogen like type iii secretion system is required for the intracellular survival of Burkholderia mallei within j774 2 macrophages
    Infection and Immunity, 2006
    Co-Authors: Wilson J Ribot, Ricky L Ulrich
    Abstract:

    Burkholderia mallei is a highly infectious gram-negative pathogen and is the causative agent of human and animal glanders. By generating polar mutations (disruption of bsaQ and bsaZ) in the B. mallei ATCC 23344 animal pathogen-like type III secretion system (TTS), we demonstrate that this bacterial protein delivery system is required for intracellular growth of B. mallei in J774.2 cells, formation of macrophage membrane protrusions, actin polymerization, and phagosomal escape. These findings suggest that TTS plays a role in the intracellular trafficking of B. mallei and may facilitate cell-to-cell spread via actin-based motility.

  • using real time pcr to specifically detect Burkholderia mallei
    Journal of Medical Microbiology, 2006
    Co-Authors: Melanie P Ulrich, David A Norwood, Deanna R Christensen, Ricky L Ulrich
    Abstract:

    Burkholderia mallei is the causative agent of human and animal glanders and is a category B biothreat agent. Rapid diagnosis of B. mallei and immediate prophylactic treatment are essential for patient survival. The majority of current bacteriological and immunological techniques for identifying B. mallei from clinical samples are time-consuming, and cross-reactivity with closely related organisms (i.e. Burkholderia pseudomallei) is a problem. In this investigation, two B. mallei-specific real-time PCR assays targeting the B. mallei bimA ma gene ( Burkholderia intracellular motility A; BMAA0749), which encodes a protein involved in actin polymerization, were developed. The PCR primer and probe sets were tested for specificity against a collection of B. mallei and B. pseudomallei isolates obtained from numerous clinical and environmental (B. pseudomallei only) sources. The assays were also tested for cross-reactivity using template DNA from 14 closely related Burkholderia species. The relative limit of detection for the assays was found to be 1 pg or 424 genome equivalents. The authors also analysed the applicability of assays to detect B. mallei within infected BALB/c mouse tissues. Beginning 1 h post aerosol exposure, B. mallei was successfully identified within the lungs, and starting at 24 h post exposure, in the spleen and liver. Surprisingly, B. mallei was not detected in the blood of acutely infected animals. This investigation provides two real-time PCR assays for the rapid and specific identification of B. mallei.

  • actin binding proteins from Burkholderia mallei and Burkholderia thailandensis can functionally compensate for the actin based motility defect of a Burkholderia pseudomallei bima mutant
    Journal of Bacteriology, 2005
    Co-Authors: Joanne M Stevens, David Deshazer, Ricky L Ulrich, Lowrie A Taylor, Michael W Wood, Mark P Stevens, Edouard E Galyov
    Abstract:

    Recently we identified a bacterial factor (BimA) required for actin-based motility of Burkholderia pseudomallei. Here we report that Burkholderia mallei and Burkholderia thailandensis are capable of actin-based motility in J774.2 cells and that BimA homologs of these bacteria can restore the actin-based motility defect of a B. pseudomallei bimA mutant. While the BimA homologs differ in their amino-terminal sequence, they interact directly with actin in vitro and vary in their ability to bind Arp3.

Alfredo G Torres - One of the best experts on this subject based on the ideXlab platform.

  • Burkholderia mallei clh001 attenuated vaccine strain is immunogenic and protects against acute respiratory glanders
    Infection and Immunity, 2016
    Co-Authors: Christopher L. Hatcher, Laura A. Muruato, Tiffany M Mott, Elena Sbrana, Alfredo G Torres
    Abstract:

    ABSTRACT Burkholderia mallei is the causative agent of glanders, an incapacitating disease with high mortality rates in respiratory cases. Its endemicity and ineffective treatment options emphasize its public health threat and highlight the need for a vaccine. Live attenuated vaccines are considered the most viable vaccine strategy for Burkholderia, but single-gene-deletion mutants have not provided complete protection. In this study, we constructed the select-agent-excluded B. mallei ΔtonB Δhcp1 (CLH001) vaccine strain and investigated its ability to protect against acute respiratory glanders. Here we show that CLH001 is attenuated, safe, and effective at protecting against lethal B. mallei challenge. Intranasal administration of CLH001 to BALB/c and NOD SCID gamma (NSG) mice resulted in complete survival without detectable colonization or abnormal organ histopathology. Additionally, BALB/c mice intranasally immunized with CLH001 in a prime/boost regimen were fully protected against lethal challenge with the B. malleilux (CSM001) wild-type strain.

  • Recent Advances in Burkholderia mallei and B. pseudomallei Research
    Current Tropical Medicine Reports, 2015
    Co-Authors: Christopher L. Hatcher, Laura A. Muruato, Alfredo G Torres
    Abstract:

    Burkholderia mallei and Burkholderia pseudomallei are Gram-negative organisms, which are etiological agents of glanders and melioidosis, respectively. Although only B. pseudomallei is responsible for a significant number of human cases, both organisms are classified as Tier 1 Select Agents and their diseases lack effective diagnosis and treatment. Despite a recent resurgence in research pertaining to these organisms, there are still a number of knowledge gaps. This article summarizes the latest research progress in the fields of B. mallei and B. pseudomallei pathogenesis, vaccines, and diagnostics.

  • a gold nanoparticle linked glycoconjugate vaccine against Burkholderia mallei
    Nanomedicine: Nanotechnology Biology and Medicine, 2015
    Co-Authors: Anthony E Gregory, Barbara M Judy, Alfredo G Torres, Omar I Qazi, Carla A Blumentritt, Katherine A Brown, Andrew M Shaw, Richard W Titball
    Abstract:

    Abstract Burkholderia mallei are Gram-negative bacteria, responsible for the disease glanders. B. mallei has recently been classified as a Tier 1 agent owing to the fact that this bacterial species can be weaponised for aerosol release, has a high mortality rate and demonstrates multi-drug resistance. Furthermore, there is no licensed vaccine available against this pathogen. Lipopolysaccharide (LPS) has previously been identified as playing an important role in generating host protection against Burkholderia infection. In this study, we present gold nanoparticles (AuNPs) functionalised with a glycoconjugate vaccine against glanders. AuNPs were covalently coupled with one of three different protein carriers (TetHc, Hcp1 and FliC) followed by conjugation to LPS purified from a non-virulent clonal relative, B. thailandensis . Glycoconjugated LPS generated significantly higher antibody titres compared with LPS alone. Further, they improved protection against a lethal inhalation challenge of B. mallei in the murine model of infection. From the Clinical Editor Burkholderia mallei is associated with multi-drug resistance, high mortality and potentials for weaponization through aerosol inhalation. The authors of this study present gold nanoparticles (AuNPs) functionalized with a glycoconjugate vaccine against this Gram negative bacterium demonstrating promising results in a murine model even with the aerosolized form of B. mallei.

  • comparison of the in vitro and in vivo susceptibilities of Burkholderia mallei to ceftazidime and levofloxacin
    BMC Microbiology, 2009
    Co-Authors: Barbara M Judy, Gregory C Whitlock, Alfredo G Torres, Mark D Estes
    Abstract:

    Background Burkholderia mallei is a zoonotic Gram negative bacterium which primarily infects solipeds but can cause lethal disease in humans if left untreated. The effect of two antibiotics with different modes of action on Burkholderia mallei strain ATCC23344 was investigated by using in vitro and in vivo studies.

  • Burkholderia mallei cellular interactions in a respiratory cell model
    Journal of Medical Microbiology, 2009
    Co-Authors: Gregory C Whitlock, Barbara M Judy, Mark D Estes, Gustavo Valbuena, Vsevolod L Popov, Alfredo G Torres
    Abstract:

    Burkholderia mallei is a facultative intracellular pathogen that survives and replicates in phagocytic cell lines. The bacterial burden recovered from naive BALB/c mice infected by intranasal delivery indicated that B. mallei persists in the lower respiratory system. To address whether B. mallei invades respiratory non-professional phagocytes, this study utilized A549 and LA-4 respiratory epithelial cells and demonstrated that B. mallei possesses the capacity to adhere poorly to, but not to invade, these cells. Furthermore, it was found that B. mallei was taken up by the murine alveolar macrophage cell line MH-S following serum coating, an attribute suggestive of complement- or Fc receptor-mediated uptake. Invasion/intracellular survival assays of B. mallei-infected MH-S cells demonstrated decreased intracellular survival, whilst a type III secretion system effector bopA mutant strain survived longer than the wild-type. Evaluation of the potential mechanism(s) responsible for efficient clearing of intracellular organisms demonstrated comparable levels of caspase-3 in both the wild-type and bopA mutant with characteristics consistent with apoptosis of infected MH-S cells. Furthermore, challenge of BALB/c mice with the bopA mutant by the intranasal route resulted in increased survival. Overall, these data suggest that B. mallei induces apoptotic cell death, whilst the BopA effector protein participates in intracellular survival.

Mark D Estes - One of the best experts on this subject based on the ideXlab platform.

  • use of the common marmoset to study Burkholderia mallei infection
    PLOS ONE, 2015
    Co-Authors: Tomislav P Jelesijevic, Mark D Estes, Frank Michel, Robert J Hogan, Shawn M Zimmerman, Stephen B Harvey, Daniel G Mead, Teresa L Shaffer, Frederick D Quinn, Eric R Lafontaine
    Abstract:

    Burkholderia mallei is a host-adapted bacterium that does not persist outside of its equine reservoir. The organism causes the zoonosis glanders, which is endemic in Asia, Africa, the Middle East and South America. Infection by B. mallei typically occurs via the respiratory or percutaneous route, and the most common manifestations are life-threatening pneumonia and bacteremia. Glanders is difficult to diagnose and requires prolonged antibiotic therapy with low success rates. There is no vaccine to protect against B. mallei and there is concern regarding its use as a biothreat agent. Thus, experiments were performed to establish a non-human primate model of intranasal infection to study the organism and develop countermeasures. Groups of marmosets (Callithrix jacchus) were inoculated intranasally with B. mallei strain ATCC 23344 and monitored for clinical signs of illness for up to 13 days. We discovered that 83% of marmosets inoculated with doses of 2.5 X 104 to 2.5 X 105 bacteria developed acute lethal infection within 3–4 days. Signs of disease were severe and included lethargy, inappetence, conjunctivitis, mucopurulent and hemorrhagic nasal discharges, and increased respiratory effort with abdominal lifts. Burkholderia mallei was cultured from the lungs, spleen and liver of these animals, and pathologic examination of tissues revealed lesions characteristic of glanders. Challenge experiments also revealed that 91% of animals infected with doses ranging from 25 to 2.5 X 103 bacteria exhibited mild non-specific signs of illness and were culture negative. One marmoset inoculated with 2.5 X 103 organisms developed moderate signs of disease and reached humane end-points 8 days post-infection. The liver and spleen of this animal were colonized with the agent and pathological analysis of tissues showed nasal, splenic and hepatic lesions. Taken together, these data indicate that the marmoset is a suitable model to study respiratory infection by B. mallei.

  • comparison of the in vitro and in vivo susceptibilities of Burkholderia mallei to ceftazidime and levofloxacin
    BMC Microbiology, 2009
    Co-Authors: Barbara M Judy, Gregory C Whitlock, Alfredo G Torres, Mark D Estes
    Abstract:

    Background Burkholderia mallei is a zoonotic Gram negative bacterium which primarily infects solipeds but can cause lethal disease in humans if left untreated. The effect of two antibiotics with different modes of action on Burkholderia mallei strain ATCC23344 was investigated by using in vitro and in vivo studies.

  • Burkholderia mallei cellular interactions in a respiratory cell model
    Journal of Medical Microbiology, 2009
    Co-Authors: Gregory C Whitlock, Barbara M Judy, Mark D Estes, Gustavo Valbuena, Vsevolod L Popov, Alfredo G Torres
    Abstract:

    Burkholderia mallei is a facultative intracellular pathogen that survives and replicates in phagocytic cell lines. The bacterial burden recovered from naive BALB/c mice infected by intranasal delivery indicated that B. mallei persists in the lower respiratory system. To address whether B. mallei invades respiratory non-professional phagocytes, this study utilized A549 and LA-4 respiratory epithelial cells and demonstrated that B. mallei possesses the capacity to adhere poorly to, but not to invade, these cells. Furthermore, it was found that B. mallei was taken up by the murine alveolar macrophage cell line MH-S following serum coating, an attribute suggestive of complement- or Fc receptor-mediated uptake. Invasion/intracellular survival assays of B. mallei-infected MH-S cells demonstrated decreased intracellular survival, whilst a type III secretion system effector bopA mutant strain survived longer than the wild-type. Evaluation of the potential mechanism(s) responsible for efficient clearing of intracellular organisms demonstrated comparable levels of caspase-3 in both the wild-type and bopA mutant with characteristics consistent with apoptosis of infected MH-S cells. Furthermore, challenge of BALB/c mice with the bopA mutant by the intranasal route resulted in increased survival. Overall, these data suggest that B. mallei induces apoptotic cell death, whilst the BopA effector protein participates in intracellular survival.

  • glanders off to the races with Burkholderia mallei
    Fems Microbiology Letters, 2007
    Co-Authors: Gregory C Whitlock, Mark D Estes, Alfredo G Torres
    Abstract:

    Burkholderia mallei, the etiologic agent of the disease known as glanders, is primarily a disease affecting horses and is transmitted to humans by direct contact with infected animals. The use of B. mallei as a biological weapon has been reported and currently, there is no vaccine available for either humans or animals. Despite the history and highly infective nature of B. mallei, as well as its potential use as a bio-weapon, B. mallei research to understand the pathogenesis and the host responses to infection remains limited. Therefore, this minireview will focus on current efforts to elucidate B. mallei virulence, the associated host immune responses elicited during infection and discuss the feasibility of vaccine development.

David M Waag - One of the best experts on this subject based on the ideXlab platform.

  • Characterization of in vitro phenotypes of Burkholderia pseudomallei and Burkholderia mallei strains potentially associated with persistent infection in mice
    Archives of Microbiology, 2016
    Co-Authors: R. C. Bernhards, David M Waag, Kei Amemiya, Christopher K. Cote, Christopher P. Klimko, Patricia L. Worsham, Susan L. Welkos
    Abstract:

    Burkholderia pseudomallei (Bp) and Burkholderia mallei (Bm), the agents of melioidosis and glanders, respectively, are Tier 1 biothreats. They infect humans and animals, causing disease ranging from acute and fatal to protracted and chronic. Chronic infections are especially challenging to treat, and the identification of in vitro phenotypic markers which signal progression from acute to persistent infection would be extremely valuable. First, a phenotyping strategy was developed employing colony morphotyping, chemical sensitivity testing, macrophage infection, and lipopolysaccharide fingerprint analyses to distinguish Burkholderia strains. Then mouse spleen isolates collected 3–180 days after infection were characterized phenotypically. Isolates from long-term infections often exhibited increased colony morphology differences and altered patterns of antimicrobial sensitivity and macrophage infection. Some of the Bp and Bm persistent infection isolates clearly displayed enhanced virulence in mice. Future studies will evaluate the potential role and significance of these phenotypic markers in signaling the establishment of a chronic infection.

  • distinct human antibody response to the biological warfare agent Burkholderia mallei
    Virulence, 2012
    Co-Authors: John J Varga, David Deshazer, David M Waag, Adam Vigil, Philip L Felgner, Joanna B Goldberg
    Abstract:

    The genetic similarity between Burkholderia mallei (glanders) and Burkholderia pseudomallei (melioidosis) had led to the general assumption that pathogenesis of each bacterium would be similar. In 2000, the first human case of glanders in North America since 1945 was reported in a microbiology laboratory worker. Leveraging the availability of pre-exposure sera for this individual and employing the same well-characterized protein array platform that has been previously used to study a large cohort of melioidosis patients in southeast Asia, we describe the antibody response in a human with glanders. Analysis of 156 peptides present on the array revealed antibodies against 17 peptides with a > 2-fold increase in this infection. Unexpectedly, when the glanders data were compared with a previous data set from B. pseudomallei infections, there were only two highly increased antibodies shared between these two infections. These findings have implications in the diagnosis and treatment of B. mallei and B. pseudomallei infections.

  • the type iv pilin of Burkholderia mallei is highly immunogenic but fails to protect against lethal aerosol challenge in a murine model
    Infection and Immunity, 2007
    Co-Authors: Paula J Fernandes, David M Waag, Michael S Donnenberg
    Abstract:

    Burkholderia mallei is the cause of glanders and a proven biological weapon. We identified and purified the type IV pilin protein of this organism to study its potential as a subunit vaccine. We found that purified pilin was highly immunogenic. Furthermore, mice infected via sublethal aerosol challenge developed significant increases in titers of antibody against the pilin, suggesting that it is expressed in vivo. Nevertheless, we found no evidence that high-titer antipilin antisera provided passive protection against a sublethal or lethal aerosol challenge and no evidence of protection afforded by active immunization with purified pilin. These results contrast with the utility of type IV pilin subunit vaccines against other infectious diseases and highlight the need for further efforts to identify protective responses against this pathogen.

  • polysaccharide microarray technology for the detection of Burkholderia pseudomallei and Burkholderia mallei antibodies
    Diagnostic Microbiology and Infectious Disease, 2006
    Co-Authors: Narayanan Parthasarathy, David Deshazer, Marilyn J England, David M Waag
    Abstract:

    A polysaccharide microarray platform was prepared by immobilizing Burkholderia pseudomallei and Burkholderia mallei polysaccharides. This polysaccharide array was tested with success for detecting B. pseudomallei and B. mallei serum (human and animal) antibodies. The advantages of this microarray technology over the current serodiagnosis of the above bacterial infections were discussed.

  • monoclonal antibodies passively protect balb c mice against Burkholderia mallei aerosol challenge
    Infection and Immunity, 2006
    Co-Authors: Sylvia R Trevino, Amy R Permenter, Marilyn J England, Narayanan Parthasarathy, Paul Gibbs, David M Waag, Tran C Chanh
    Abstract:

    Glanders is a debilitating disease with no vaccine available. Murine monoclonal antibodies were produced against Burkholderia mallei, the etiologic agent of glanders, and were shown to be effective in passively protecting mice against a lethal aerosol challenge. The antibodies appeared to target lipopolysaccharide. Humoral antibodies may be important for immune protection against B. mallei infection.