Protective response to subunit vaccination against intranasal Burkholderia mallei and B. pseudomallei challenge

Procedia in Vaccinology 12/2010; 2(1):73-77. DOI: 10.1016/j.provac.2010.03.013


Burkholderia mallei and B. pseudomallei are Gram-negative pathogenic bacteria, responsible for the diseases glanders and melioidosis, respectively. Furthermore, there is currently no vaccine available against these Burkholderia species. In this study, we aimed to identify protective proteins against these pathogens. Immunization with recombinant B. mallei Hcp1 (type VI secreted/structural protein), BimA (autotransporter protein), BopA (type III secreted protein), and B. pseudomallei LolC (ABC transporter protein) generated significant protection against lethal inhaled B. mallei ATCC23344 and B. pseudomallei 1026b challenge. Immunization with BopA elicited the greatest protective activity, resulting in 100% and 60% survival against B. mallei and B. pseudomallei challenge, respectively. Moreover, sera from recovered mice demonstrated reactivity with the recombinant proteins. Dendritic cells stimulated with each of the different recombinant proteins showed distinct cytokine patterns. In addition, T cells from immunized mice produced IFN-γ following in vitro re-stimulation. These results indicated therefore that it was possible to elicit cross-protective immunity against both B. mallei and B. pseudomallei by vaccinating animals with one or more novel recombinant proteins identified in B. mallei.

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Available from: Don Mark Estes, Sep 30, 2015
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    • "Cloning and protein expression protocols were followed as described previously (Whitlock et al., 2010). Briefly, target sequences were subjected to bioinformatics analysis using SignalP v.3.0 (Bendtsen et al., 2004), TMHMM v.2.0 (Krogh et al., 2001), and PHYRE v.0.2 (Kelley et al., 2009) to identify putative N-terminal amino acid (AA) secretion sequences, transmembrane domains, and homologies to published crystal structures, respectively. "
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    Frontiers in Microbiology 11/2011; 2:227. DOI:10.3389/fmicb.2011.00227 · 3.99 Impact Factor
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    ABSTRACT: Rapid detection of the category B biothreat agents Burkholderia pseudomallei and Burkholderia mallei in acute infections is critical to ensure that appropriate treatment is administered quickly to reduce an otherwise high probability of mortality (ca. 40% for B. pseudomallei). We are developing assays that can be used in clinical laboratories or security applications for the direct detection of surface-localized and secreted macromolecules produced by these organisms. We present our current medium-throughout approach for target selection and production of Burkholderia macromolecules and describe the generation of a Fab molecule targeted to the B. mallei BimA protein. We also present development of prototype assays for detecting Burkholderia species using anti-lipopolysaccharide antibodies.
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