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Gaspar EB, dos Santos LR, do Egito AA, dos Santos MG, Mantovani C, Rieger JDSG, Abrantes GADS, Suniga PAP, Favacho JDM, Pinto IB, Nassar AFDC, dos Santos FL, de Araújo FR. Assessment of the Virulence of the Burkholderia mallei Strain BAC 86/19 in BALB/c Mice. Microorganisms 2023; 11:2597. [PMID: 37894255 PMCID: PMC10609534 DOI: 10.3390/microorganisms11102597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 10/09/2023] [Accepted: 10/13/2023] [Indexed: 10/29/2023] Open
Abstract
Burkholderia mallei is an aerobic, Gram-negative, non-motile bacillus. As an obligate mammalian pathogen, it primarily affects solipeds. Although rarely transmitted to humans, the disease it causes, glanders, is classified as a zoonosis. The bacterium was officially eradicated in Brazil in 1969; however, it reemerged after three decades. This study aims to assess the virulence of a specific B. mallei strain, isolated in Brazil, in BALB/c mice through intranasal infection. The strain, B. mallei BAC 86/19, was obtained from the tracheal secretion of a young mare displaying positive serology but no clinical signs of glanders. Post-mortem examinations revealed macroscopic lesions consistent with the disease, however. In mice, the LD50 was determined to be approximately 1.59 × 105 colony-forming units (CFU)/animal. Mice exposed to either 0.1 × LD50 or 1 × LD50 displayed transient weight loss, which resolved after three or five days, respectively. B. mallei persisted within the liver and lung for five days post-infection and in the spleen for seven days. These findings underscore the detectable virulence of the Brazilian B. mallei BAC 86/19 strain in mice, which are relatively resilient hosts. This research points to the importance of the continued investigation of the virulence mechanisms and potential countermeasures associated with B. mallei infections, including their Brazilian isolates.
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Affiliation(s)
- Emanuelle Baldo Gaspar
- Embrapa South Livestock, BR-153, Km 632, 9 Vila Industrial, Rural Area, Mailbox 242, Bagé 96401-970, RS, Brazil
| | - Lenita Ramires dos Santos
- Embrapa Beef Cattle, Rádio Maia Ave., 830, Campo Grande 79106-550, MS, Brazil; (L.R.d.S.); (A.A.d.E.); (M.G.d.S.); (F.R.d.A.)
| | - Andréa Alves do Egito
- Embrapa Beef Cattle, Rádio Maia Ave., 830, Campo Grande 79106-550, MS, Brazil; (L.R.d.S.); (A.A.d.E.); (M.G.d.S.); (F.R.d.A.)
| | - Maria Goretti dos Santos
- Embrapa Beef Cattle, Rádio Maia Ave., 830, Campo Grande 79106-550, MS, Brazil; (L.R.d.S.); (A.A.d.E.); (M.G.d.S.); (F.R.d.A.)
| | - Cynthia Mantovani
- Embrapa Beef Cattle/Ministry of Agriculture, Livestock and Food Supply Scholarship, Embrapa Beef Cattle, Rádio Maia Ave., 830, Campo Grande 79106-550, MS, Brazil; (C.M.); (J.d.S.G.R.); (G.A.d.S.A.); (I.B.P.)
| | - Juliana da Silva Gomes Rieger
- Embrapa Beef Cattle/Ministry of Agriculture, Livestock and Food Supply Scholarship, Embrapa Beef Cattle, Rádio Maia Ave., 830, Campo Grande 79106-550, MS, Brazil; (C.M.); (J.d.S.G.R.); (G.A.d.S.A.); (I.B.P.)
| | - Guilherme Augusto de Sousa Abrantes
- Embrapa Beef Cattle/Ministry of Agriculture, Livestock and Food Supply Scholarship, Embrapa Beef Cattle, Rádio Maia Ave., 830, Campo Grande 79106-550, MS, Brazil; (C.M.); (J.d.S.G.R.); (G.A.d.S.A.); (I.B.P.)
| | - Paula Adas Pereira Suniga
- MAI/DAI Scholarship, Federal University of Mato Grosso do Sul, Cidade Universitária, Costa e Silva Ave., Campo Grande 79070-900, MS, Brazil;
- Postgraduate Program in Animal Science, Faculty of Veterinary Medicine and Animal Science-FAMEZ/UFMS, Federal University of Mato Grosso do Sul, Senador Filinto Muller Ave., 2443, Campo Grande 79074-460, MS, Brazil
| | | | - Ingrid Batista Pinto
- Embrapa Beef Cattle/Ministry of Agriculture, Livestock and Food Supply Scholarship, Embrapa Beef Cattle, Rádio Maia Ave., 830, Campo Grande 79106-550, MS, Brazil; (C.M.); (J.d.S.G.R.); (G.A.d.S.A.); (I.B.P.)
| | | | - Fernando Leandro dos Santos
- UFPE Department of Veterinary Medicine, Federal Rural University of Pernambuco, Recife 52171-900, PE, Brazil;
| | - Flábio Ribeiro de Araújo
- Embrapa Beef Cattle, Rádio Maia Ave., 830, Campo Grande 79106-550, MS, Brazil; (L.R.d.S.); (A.A.d.E.); (M.G.d.S.); (F.R.d.A.)
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Biryukov SS, Cote CK, Klimko CP, Dankmeyer JL, Rill NO, Shoe JL, Hunter M, Shamsuddin Z, Velez I, Hedrick ZM, Rosario-Acevedo R, Talyansky Y, Schmidt LK, Orne CE, Fetterer DP, Burtnick MN, Brett PJ, Welkos SL, DeShazer D. Evaluation of two different vaccine platforms for immunization against melioidosis and glanders. Front Microbiol 2022; 13:965518. [PMID: 36060742 PMCID: PMC9428723 DOI: 10.3389/fmicb.2022.965518] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 07/22/2022] [Indexed: 11/13/2022] Open
Abstract
Burkholderia pseudomallei and the closely related species, Burkholderia mallei, produce similar multifaceted diseases which range from rapidly fatal to protracted and chronic, and are a major cause of mortality in endemic regions. Besides causing natural infections, both microbes are Tier 1 potential biothreat agents. Antibiotic treatment is prolonged with variable results, hence effective vaccines are urgently needed. The purpose of our studies was to compare candidate vaccines that target both melioidosis and glanders to identify the most efficacious one(s) and define residual requirements for their transition to the non-human primate aerosol model. Studies were conducted in the C57BL/6 mouse model to evaluate the humoral and cell-mediated immune response and protective efficacy of three Burkholderia vaccine candidates against lethal aerosol challenges with B. pseudomallei K96243, B. pseudomallei MSHR5855, and B. mallei FMH. The recombinant vaccines generated significant immune responses to the vaccine antigens, and the live attenuated vaccine generated a greater immune response to OPS and the whole bacterial cells. Regardless of the candidate vaccine evaluated, the protection of mice was associated with a dampened cytokine response within the lungs after exposure to aerosolized bacteria. Despite being delivered by two different platforms and generating distinct immune responses, two experimental vaccines, a capsule conjugate + Hcp1 subunit vaccine and the live B. pseudomallei 668 ΔilvI strain, provided significant protection and were down-selected for further investigation and advanced development.
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Affiliation(s)
- Sergei S. Biryukov
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - Christopher K. Cote
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
- *Correspondence: Christopher K. Cote
| | - Christopher P. Klimko
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - Jennifer L. Dankmeyer
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - Nathaniel O. Rill
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - Jennifer L. Shoe
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - Melissa Hunter
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - Zain Shamsuddin
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - Ivan Velez
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - Zander M. Hedrick
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - Raysa Rosario-Acevedo
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - Yuli Talyansky
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - Lindsey K. Schmidt
- Department of Microbiology and Immunology, University of Nevada, Reno School of Medicine, Reno, NV, United States
| | - Caitlyn E. Orne
- Department of Microbiology and Immunology, University of Nevada, Reno School of Medicine, Reno, NV, United States
| | - David P. Fetterer
- Biostatistics Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - Mary N. Burtnick
- Department of Microbiology and Immunology, University of Nevada, Reno School of Medicine, Reno, NV, United States
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Paul J. Brett
- Department of Microbiology and Immunology, University of Nevada, Reno School of Medicine, Reno, NV, United States
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Susan L. Welkos
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
| | - David DeShazer
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States
- David DeShazer
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Shropshire H, Jones RA, Aguilo-Ferretjans MM, Scanlan DJ, Chen Y. Proteomics insights into the Burkholderia cenocepacia phosphorus stress response. Environ Microbiol 2021; 23:5069-5086. [PMID: 33684254 DOI: 10.1111/1462-2920.15451] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 03/02/2021] [Indexed: 11/26/2022]
Abstract
The Burkholderia cepacia complex is a group of Burkholderia species that are opportunistic pathogens causing high mortality rates in patients with cystic fibrosis. An environmental stress often encountered by these soil-dwelling and pathogenic bacteria is phosphorus limitation, an essential element for cellular processes. Here, we describe cellular and extracellular proteins differentially regulated between phosphate-deplete (0 mM, no added phosphate) and phosphate-replete (1 mM) growth conditions using a comparative proteomics (LC-MS/MS) approach. We observed a total of 128 and 65 unique proteins were downregulated and upregulated respectively, in the B. cenocepacia proteome. Of those downregulated proteins, many have functions in amino acid transport/metabolism. We have identified 24 upregulated proteins that are directly/indirectly involved in inorganic phosphate or organic phosphorus acquisition. Also, proteins involved in virulence and antimicrobial resistance were differentially regulated, suggesting B. cenocepacia experiences a dramatic shift in metabolism under these stress conditions. Overall, this study provides a baseline for further research into the biology of Burkholderia in response to phosphorus stress.
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Affiliation(s)
- Holly Shropshire
- BBSRC Midlands Integrative Biosciences Training Partnership, University of Warwick, Coventry, CV4 7AL, UK.,School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Rebekah A Jones
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | | | - David J Scanlan
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Yin Chen
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
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Wang G, Zarodkiewicz P, Valvano MA. Current Advances in Burkholderia Vaccines Development. Cells 2020; 9:E2671. [PMID: 33322641 PMCID: PMC7762980 DOI: 10.3390/cells9122671] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 12/01/2020] [Accepted: 12/09/2020] [Indexed: 12/18/2022] Open
Abstract
The genus Burkholderia includes a wide range of Gram-negative bacterial species some of which are pathogenic to humans and other vertebrates. The most pathogenic species are Burkholderia mallei, Burkholderia pseudomallei, and the members of the Burkholderia cepacia complex (Bcc). B. mallei and B. pseudomallei, the cause of glanders and melioidosis, respectively, are considered potential bioweapons. The Bcc comprises a subset of Burkholderia species associated with respiratory infections in people with chronic granulomatous disease and cystic fibrosis. Antimicrobial treatment of Burkholderia infections is difficult due to the intrinsic multidrug antibiotic resistance of these bacteria; prophylactic vaccines provide an attractive alternative to counteract these infections. Although commercial vaccines against Burkholderia infections are still unavailable, substantial progress has been made over recent years in the development of vaccines against B. pseudomallei and B. mallei. This review critically discusses the current advances in vaccine development against B. mallei, B. pseudomallei, and the Bcc.
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Affiliation(s)
| | | | - Miguel A. Valvano
- Wellcome-Wolfson Institute for Experimental Medicine, Queen’s University Belfast, Belfast BT9 7BL, UK; (G.W.); (P.Z.)
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Amemiya K, Zeng X, Bearss JJ, Cote CK, Soffler C, Bernhards RC, Dankmeyer JL, Ribot WJ, Trevino SR, Welkos SL, Worsham PL, Waag DM. Laser Scanning Confocal Microscopy Was Used to Validate the Presence of Burkholderia Pseudomallei or B. Mallei in Formalin-Fixed Paraffin Embedded Tissues. Trop Med Infect Dis 2020; 5:tropicalmed5020065. [PMID: 32365605 PMCID: PMC7345562 DOI: 10.3390/tropicalmed5020065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 04/18/2020] [Accepted: 04/20/2020] [Indexed: 11/17/2022] Open
Abstract
Burkholderia pseudomallei and B. mallei are Gram-negative, facultative intracellular bacteria that cause melioidosis and glanders, respectively. Currently, there are no vaccines for these two diseases. Animal models have been developed to evaluate vaccines and therapeutics. Tissues from infected animals, however, must be fixed in formalin and embedded in paraffin (FFPE) before analysis. A brownish staining material in infected tissues that represents the exopolysaccharide of the pathogen was seen by bright field microscopy but not the actual microorganism. Because of these results, FFPE tissue was examined by laser scanning confocal microscopy (LSCM) in an attempt to see the microorganism. Archival FFPE tissues were examined from ten mice, and five nonhuman primates after exposure to B. pseudomallei or B.mallei by LSCM. Additionally, a historical spleen biopsy from a human suspected of exposure to B. mallei was examined. B. pseudomallei was seen in many of the infected tissues from mice. Four out of five nonhuman primates were positive for the pathogen. In the human sample, B. mallei was seen in pyogranulomas in the spleen biopsy. Thus, the presence of the pathogen was validated by LSCM in murine, nonhuman primate, and human FFPE tissues.
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Affiliation(s)
- Kei Amemiya
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA; (C.K.C.); (C.S.); (J.L.D.); (W.J.R.); (S.R.T.); (S.L.W.); (P.L.W.); (D.M.W.)
- Correspondence: ; Tel.: +1-301-619-2182
| | - Xiankun Zeng
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA; (X.Z.); (J.J.B.)
| | - Jeremy J. Bearss
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA; (X.Z.); (J.J.B.)
| | - Christopher K. Cote
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA; (C.K.C.); (C.S.); (J.L.D.); (W.J.R.); (S.R.T.); (S.L.W.); (P.L.W.); (D.M.W.)
| | - Carl Soffler
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA; (C.K.C.); (C.S.); (J.L.D.); (W.J.R.); (S.R.T.); (S.L.W.); (P.L.W.); (D.M.W.)
| | - Robert C. Bernhards
- U.S. Army Combat Capabilities Development Command Chemical Biological Center, 8198 Blackhawk Road, Aberdeen Proving Ground, MD 21010, USA;
| | - Jennifer L. Dankmeyer
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA; (C.K.C.); (C.S.); (J.L.D.); (W.J.R.); (S.R.T.); (S.L.W.); (P.L.W.); (D.M.W.)
| | - Wilson J. Ribot
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA; (C.K.C.); (C.S.); (J.L.D.); (W.J.R.); (S.R.T.); (S.L.W.); (P.L.W.); (D.M.W.)
| | - Sylvia R. Trevino
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA; (C.K.C.); (C.S.); (J.L.D.); (W.J.R.); (S.R.T.); (S.L.W.); (P.L.W.); (D.M.W.)
| | - Susan L. Welkos
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA; (C.K.C.); (C.S.); (J.L.D.); (W.J.R.); (S.R.T.); (S.L.W.); (P.L.W.); (D.M.W.)
| | - Patricia L. Worsham
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA; (C.K.C.); (C.S.); (J.L.D.); (W.J.R.); (S.R.T.); (S.L.W.); (P.L.W.); (D.M.W.)
| | - David M. Waag
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA; (C.K.C.); (C.S.); (J.L.D.); (W.J.R.); (S.R.T.); (S.L.W.); (P.L.W.); (D.M.W.)
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Abstract
Purpose of review Burkholderia mallei is a facultative intracellular pathogen that causes the highly contagious and often the fatal disease, glanders. With its high rate of infectivity via aerosol and recalcitrance toward antibiotics, this pathogen is considered a potential biological threat agent. This review focuses on the most recent literature highlighting host innate immune response to B. mallei. Recent findings Recent studies focused on elucidating host innate immune responses to the novel mechanisms and virulence factors employed by B. mallei for survival. Studies suggest that pathogen proteins manipulate various cellular processes, including host ubiquitination pathways, phagosomal escape, and actin–cytoskeleton rearrangement. Immune-signaling molecules such as Toll-like receptors, nucleotode-binding oligomerization domain, myeloid differentiation primary response protein 88, and proinflammatory cytokines such as interferon-gamma and tumor necrosis factor-α, play key roles in the induction of innate immune responses. Modifications in B. mallei lipopolysaccharide, in particular, the lipid A acyl groups, stimulate immune responses via Toll-like receptor4 activation that may contribute to persistent infection. Summary Mortality is high because of septicemia and immune pathogenesis with B. mallei exposure. An effective innate immune response is critical to controlling the acute phase of the infection. Both vaccination and therapeutic approaches are necessary for complete protection against B. mallei.
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A Burkholderia pseudomallei Outer Membrane Vesicle Vaccine Provides Cross Protection against Inhalational Glanders in Mice and Non-Human Primates. Vaccines (Basel) 2017; 5:vaccines5040049. [PMID: 29232837 PMCID: PMC5748615 DOI: 10.3390/vaccines5040049] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 12/05/2017] [Accepted: 12/06/2017] [Indexed: 01/28/2023] Open
Abstract
Burkholderia mallei is a Gram-negative, non-motile, facultative intracellular bacillus and the causative agent of glanders, a highly contagious zoonotic disease. B. mallei is naturally resistant to multiple antibiotics and there is concern for its potential use as a bioweapon, making the development of a vaccine against B. mallei of critical importance. We have previously demonstrated that immunization with multivalent outer membrane vesicles (OMV) derived from B. pseudomallei provide significant protection against pneumonic melioidosis. Given that many virulence determinants are highly conserved between the two species, we sought to determine if the B. pseudomallei OMV vaccine could cross-protect against B. mallei. We immunized C57Bl/6 mice and rhesus macaques with B. pseudomallei OMVs and subsequently challenged animals with aerosolized B. mallei. Immunization with B. pseudomallei OMVs significantly protected mice against B. mallei and the protection observed was comparable to that achieved with a live attenuated vaccine. OMV immunization induced the production of B.mallei-specific serum IgG and a mixed Th1/Th17 CD4 and CD8 T cell response in mice. Additionally, immunization of rhesus macaques with B. pseudomallei OMVs provided protection against glanders and induced B.mallei-specific serum IgG in non-human primates. These results demonstrate the ability of the multivalent OMV vaccine platform to elicit cross-protection against closely-related intracellular pathogens and to induce robust humoral and cellular immune responses against shared protective antigens.
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Zimmerman SM, Long ME, Dyke JS, Jelesijevic TP, Michel F, Lafontaine ER, Hogan RJ. Use of Immunohistochemistry to Demonstrate In Vivo Expression of the Burkholderia mallei Virulence Factor BpaB During Experimental Glanders. Vet Pathol 2017; 55:258-267. [PMID: 29145795 DOI: 10.1177/0300985817736113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Burkholderia mallei causes the highly contagious and debilitating zoonosis glanders, which infects via inhalation or percutaneous inoculation and often culminates in life-threatening pneumonia and sepsis. In humans, glanders is difficult to diagnose and requires prolonged antibiotic therapy with low success rates. No vaccine exists to protect against B. mallei, and there is concern regarding its use as a bioweapon. The authors previously identified the protein BpaB as a potential target for devising therapies due to its role in adherence to host cells and the formation of biofilms in vitro and its contribution to pathogenicity in a mouse model of glanders. In the present study, the authors developed an immunostaining approach to probe tissues of experimentally infected animals and demonstrated that BpaB is produced exclusively in vivo by wild-type B. mallei in target organs from mice and marmosets. They detected the expression of BpaB by B. mallei both extracellularly and within macrophages, neutrophils, and epithelial cells in respiratory tissues (7/10 marmoset; 2/2 mouse). The authors also noted the intracellular expression of BpaB by B. mallei in macrophages in the regional lymph nodes of mice (2/2 tissues) and MALT of marmosets (4/5 tissues). It is interesting that B. mallei bacteria infecting distal organs did not express BpaB (2/2 mice; 3/3 marmosets), suggesting that the protein is not necessary for bacterial fitness in these anatomic locations. These findings underscore the value of BpaB as a target for developing medical countermeasures and provide insight into its role in pathogenesis.
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Affiliation(s)
- Shawn M Zimmerman
- 1 Department of Infectious Diseases, University of Georgia College of Veterinary Medicine, Athens, GA, USA
| | - Mackenzie E Long
- 2 Veterinary Teaching Hospital, University of Georgia College of Veterinary Medicine, Athens, GA, USA
| | - Jeremy S Dyke
- 1 Department of Infectious Diseases, University of Georgia College of Veterinary Medicine, Athens, GA, USA
| | - Tomislav P Jelesijevic
- 1 Department of Infectious Diseases, University of Georgia College of Veterinary Medicine, Athens, GA, USA
| | - Frank Michel
- 3 Department of Veterinary Biosciences and Diagnostic Imaging, University of Georgia College of Veterinary Medicine, Athens, GA, USA
| | - Eric R Lafontaine
- 1 Department of Infectious Diseases, University of Georgia College of Veterinary Medicine, Athens, GA, USA
| | - Robert J Hogan
- 1 Department of Infectious Diseases, University of Georgia College of Veterinary Medicine, Athens, GA, USA.,3 Department of Veterinary Biosciences and Diagnostic Imaging, University of Georgia College of Veterinary Medicine, Athens, GA, USA
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Antibodies against In Vivo-Expressed Antigens Are Sufficient To Protect against Lethal Aerosol Infection with Burkholderia mallei and Burkholderia pseudomallei. Infect Immun 2017; 85:IAI.00102-17. [PMID: 28507073 DOI: 10.1128/iai.00102-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Accepted: 05/08/2017] [Indexed: 12/22/2022] Open
Abstract
Burkholderia mallei, a facultative intracellular bacterium and tier 1 biothreat, causes the fatal zoonotic disease glanders. The organism possesses multiple genes encoding autotransporter proteins, which represent important virulence factors and targets for developing countermeasures in pathogenic Gram-negative bacteria. In the present study, we investigated one of these autotransporters, BatA, and demonstrate that it displays lipolytic activity, aids in intracellular survival, is expressed in vivo, elicits production of antibodies during infection, and contributes to pathogenicity in a mouse aerosol challenge model. A mutation in the batA gene of wild-type strain ATCC 23344 was found to be particularly attenuating, as BALB/c mice infected with the equivalent of 80 median lethal doses cleared the organism. This finding prompted us to test the hypothesis that vaccination with the batA mutant strain elicits protective immunity against subsequent infection with wild-type bacteria. We discovered that not only does vaccination provide high levels of protection against lethal aerosol challenge with B. mallei ATCC 23344, it also protects against infection with multiple isolates of the closely related organism and causative agent of melioidosis, Burkholderia pseudomallei Passive-transfer experiments also revealed that the protective immunity afforded by vaccination with the batA mutant strain is predominantly mediated by IgG antibodies binding to antigens expressed exclusively in vivo Collectively, our data demonstrate that BatA is a target for developing medical countermeasures and that vaccination with a mutant lacking expression of the protein provides a platform to gain insights regarding mechanisms of protective immunity against B. mallei and B. pseudomallei, including antigen discovery.
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Abstract
Purpose of review Burkholderia pseudomallei's and Burkholderia mallei's high rate of infectivity, limited treatment options, and potential use as biological warfare agents underscore the need for development of effective vaccines against these bacteria. Research efforts focused on vaccines against these bacteria are in pre-clinical stages, with no approved formulations currently on the market. Recent findings Several live attenuated and subunit vaccine formulations have been evaluated in animal studies, with no reports of significant long term survival after lethal challenge. Summary This review encompasses the most current vaccine strategies to prevent B. pseudomallei and B. mallei infections while providing insight for successful vaccines moving forward.
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Memišević V, Kumar K, Zavaljevski N, DeShazer D, Wallqvist A, Reifman J. DBSecSys 2.0: a database of Burkholderia mallei and Burkholderia pseudomallei secretion systems. BMC Bioinformatics 2016; 17:387. [PMID: 27650316 PMCID: PMC5029111 DOI: 10.1186/s12859-016-1242-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 09/08/2016] [Indexed: 01/08/2023] Open
Abstract
Background Burkholderia mallei and B. pseudomallei are the causative agents of glanders and melioidosis, respectively, diseases with high morbidity and mortality rates. B. mallei and B. pseudomallei are closely related genetically; B. mallei evolved from an ancestral strain of B. pseudomallei by genome reduction and adaptation to an obligate intracellular lifestyle. Although these two bacteria cause different diseases, they share multiple virulence factors, including bacterial secretion systems, which represent key components of bacterial pathogenicity. Despite recent progress, the secretion system proteins for B. mallei and B. pseudomallei, their pathogenic mechanisms of action, and host factors are not well characterized. Results We previously developed a manually curated database, DBSecSys, of bacterial secretion system proteins for B. mallei. Here, we report an expansion of the database with corresponding information about B. pseudomallei. DBSecSys 2.0 contains comprehensive literature-based and computationally derived information about B. mallei ATCC 23344 and literature-based and computationally derived information about B. pseudomallei K96243. The database contains updated information for 163 B. mallei proteins from the previous database and 61 additional B. mallei proteins, and new information for 281 B. pseudomallei proteins associated with 5 secretion systems, their 1,633 human- and murine-interacting targets, and 2,400 host-B. mallei interactions and 2,286 host-B. pseudomallei interactions. The database also includes information about 13 pathogenic mechanisms of action for B. mallei and B. pseudomallei secretion system proteins inferred from the available literature or computationally. Additionally, DBSecSys 2.0 provides details about 82 virulence attenuation experiments for 52 B. mallei secretion system proteins and 98 virulence attenuation experiments for 61 B. pseudomallei secretion system proteins. We updated the Web interface and data access layer to speed-up users’ search of detailed information for orthologous proteins related to secretion systems of the two pathogens. Conclusions The updates of DBSecSys 2.0 provide unique capabilities to access comprehensive information about secretion systems of B. mallei and B. pseudomallei. They enable studies and comparisons of corresponding proteins of these two closely related pathogens and their host-interacting partners. The database is available at http://dbsecsys.bhsai.org.
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Affiliation(s)
- Vesna Memišević
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, Fort Detrick, MD 21702, USA
| | - Kamal Kumar
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, Fort Detrick, MD 21702, USA
| | - Nela Zavaljevski
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, Fort Detrick, MD 21702, USA
| | - David DeShazer
- Bacteriology Division, U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA
| | - Anders Wallqvist
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, Fort Detrick, MD 21702, USA
| | - Jaques Reifman
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, Fort Detrick, MD 21702, USA.
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Burkholderia mallei CLH001 Attenuated Vaccine Strain Is Immunogenic and Protects against Acute Respiratory Glanders. Infect Immun 2016; 84:2345-54. [PMID: 27271739 DOI: 10.1128/iai.00328-16] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 05/26/2016] [Indexed: 11/20/2022] Open
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. mallei lux (CSM001) wild-type strain.
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