Development of Melioidosis Subunit Vaccines Using an Enzymatically Inactive Burkholderia pseudomallei AhpC
Issued Date
2022-08-01
Resource Type
ISSN
00199567
eISSN
10985522
Scopus ID
2-s2.0-85136910715
Pubmed ID
35862715
Journal Title
Infection and Immunity
Volume
90
Issue
8
Rights Holder(s)
SCOPUS
Bibliographic Citation
Infection and Immunity Vol.90 No.8 (2022)
Suggested Citation
Schmidt L.K., Orne C.E., Shaffer T.L., Wilson S.M., Khakhum N., Torres A.G., Brett P.J., Burtnick M.N. Development of Melioidosis Subunit Vaccines Using an Enzymatically Inactive Burkholderia pseudomallei AhpC. Infection and Immunity Vol.90 No.8 (2022). doi:10.1128/iai.00222-22 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/84941
Title
Development of Melioidosis Subunit Vaccines Using an Enzymatically Inactive Burkholderia pseudomallei AhpC
Other Contributor(s)
Abstract
Burkholderia pseudomallei, the causative agent of melioidosis, is a facultative intracellular, Gram-negative pathogen that is highly infectious via the respiratory route and can cause severe, debilitating, and often fatal diseases in humans and animals. At present, no licensed vaccines for immunization against this CDC Tier 1 select agent exist. Studies in our lab have previously demonstrated that subunit vaccine formulations consisting of a B. pseudomallei capsular polysaccharide (CPS)-based glycoconjugate (CPS-CRM197) combined with hemolysin-coregulated protein (Hcp1) provided C57BL/6 mice with high-level protection against an acute inhalational challenge of B. pseudomallei. In this study, we evaluated the immunogenicity and protective capacity of B. pseudomallei alkyl hydroperoxide reductase subunit C (AhpC) in combination with CPS-CRM197. AhpC is a peroxiredoxin involved in oxidative stress reduction and is a potential protective antigen. To facilitate our studies and maximize safety in animals, recombinant B. pseudomallei AhpC harboring an active site mutation (AhpCC57G) was expressed in Escherichia coli and purified using tandem nickel-cobalt affinity chromatography. Immunization of C57BL/6 mice with CPSCRM197 combined with AhpCC57G stimulated high-titer IgG responses against the CPS component of the glycoconjugate as well as stimulated high-titer IgG and robust interferon gamma (IFN-g)-, interleukin-5 (IL-5)-, and IL-17-secreting T cell responses against AhpCC57G. When challenged via an inhalational route with a high dose (;27 50% lethal doses [LD50s]) of B. pseudomallei, 70% of the immunized mice survived 35 days postchallenge. Collectively, our findings demonstrate that AhpCC57G is a potent activator of cellular and humoral immune responses and may be a promising candidate to include in future melioidosis subunit vaccines.