A Q fever vaccine remains an important public health and national security goal. The objective of this application is to clone the O antigen epitopes from C. burnetii lipopolysaccharide (LPS) expressed on a heterologous LPS lipid A and core or N-linked glycoprotein, and combine this with protective T cellstimulating recombinant proteins in Recombinant Attenuated Salmonella Vaccines (RASV). The vaccine candidates will be characterized for the protective capacity of recombinant antigens that confer strong T-cell responses in vaccine-induced and infection-derived immunity in BL6 and MHC ll-humanized (DR1 or DR4) mice and outbred guinea pigs. We will accomplish the objective by pursuing the following specific aims: (1) Identify and characterize genes required forsubunit LPS O-antigen expression. Protective carbohydrate epitopes on the O-side chain of C. burnetii LPS can be expressed on a heterologous lipid A-core acceptor in Salmonella by cloning essential genes encoding the biosynthetic pathways for O antigen synthesis. Selection for recombinant O antigen carbohydrate synthesis will include phage resistance, LPS-specific antibody reactivity, and direct cloning of predicted genes for O antigen synthesis. (2) Heterologously express O polysaccharide as an N-linked glycoprotein. Protective carbohydrate epitopes on the O-side chain of C. burnetii LPS will be expressed as an N-linked glycoprotein using the transferase (PgIB) and acceptor (AcrA) proteins from Campylobacterjejuni. The coupled O side chain carbohydrates will be purified, and structurally and antigenically characterized. A C. burnetii antigenic protein (Com-1) will be modified with an acceptor motif to replace AcrA and evaluated for the ability to act as an antigenic N-linked carrier protein. (3) Identify and characterize mimetope peptides that antigenically model O-polysaccharide. Combinatorial peptide libraries will be screened for targets that cross react with antibody specific for C. burnetii O polysaccharide. These peptides will be tested for protective antibody responses upon vaccination by recognizing C. burnetii LPS. Candidate peptides will be conjugated to KLH or TT carrier protein and used to stimulate antibody responses in mice. (4) Evaluate the protective capacity of heterologously expressed C. burnetii Oside chain carbohydrates and proteins in mouse and guinea pig challenge models. Live RASV, microvesicles prepared from RASV, and purified recombinant proteins conjugated to heterologous LPS will be compared.

Public Health Relevance

Vaccine development is a primary focus of the RCE system and the WRCE. C. burnetii is an understudied Select Agent in the RCE system, and the WRCE provides important coverage of the agent in meeting the goals outlined by NIH. Support for the development of a relevant animal model (guinea pig aerosol) in the first funding cycle translated into a tool used in this renewal application for vaccine development. Ongoing, separately funded studies to identify T-cell protein epitopes, both CD4 (NIH, RO1 Samuel, PI) and CD8 (PSRCE, Peters PI, Samuel subcontract), will be used to support the ultimate protein partner choices for combination with LPS epitopes.

National Institute of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
Specialized Center--Cooperative Agreements (U54)
Project #
Application #
Study Section
Special Emphasis Panel (ZAI1-DDS-M)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Texas Medical Br Galveston
United States
Zip Code
Navarro, Juan-Carlos; Giambalvo, Dileyvic; Hernandez, Rosa et al. (2016) Isolation of Madre de Dios Virus (Orthobunyavirus; Bunyaviridae), an Oropouche Virus Species Reassortant, from a Monkey in Venezuela. Am J Trop Med Hyg 95:328-38
Park, Arnold; Yun, Tatyana; Hill, Terence E et al. (2016) Optimized P2A for reporter gene insertion into Nipah virus results in efficient ribosomal skipping and wild-type lethality. J Gen Virol 97:839-43
Aghazadeh, Amirali; Lin, Adam Y; Sheikh, Mona A et al. (2016) Universal microbial diagnostics using random DNA probes. Sci Adv 2:e1600025
Inglis, Fiona M; Lee, Kim M; Chiu, Kevin B et al. (2016) Neuropathogenesis of Chikungunya infection: astrogliosis and innate immune activation. J Neurovirol 22:140-8
Hatcher, Christopher L; Mott, Tiffany M; Muruato, Laura A et al. (2016) Burkholderia mallei CLH001 Attenuated Vaccine Strain Is Immunogenic and Protects against Acute Respiratory Glanders. Infect Immun 84:2345-54
Chen, Hui; Hagström, Anna E V; Kim, Jinsu et al. (2016) Flotation Immunoassay: Masking the Signal from Free Reporters in Sandwich Immunoassays. Sci Rep 6:24297
Crannell, Zachary Austin; Cabada, Miguel Mauricio; Castellanos-Gonzalez, Alejandro et al. (2015) Recombinase polymerase amplification-based assay to diagnose Giardia in stool samples. Am J Trop Med Hyg 92:583-7
Walker, David H; Dumler, J Stephen (2015) The role of CD8 T lymphocytes in rickettsial infections. Semin Immunopathol 37:289-99
Mott, Tiffany M; Vijayakumar, Sudhamathi; Sbrana, Elena et al. (2015) Characterization of the Burkholderia mallei tonB Mutant and Its Potential as a Backbone Strain for Vaccine Development. PLoS Negl Trop Dis 9:e0003863
Gregory, Anthony E; Judy, Barbara M; Qazi, Omar et al. (2015) A gold nanoparticle-linked glycoconjugate vaccine against Burkholderia mallei. Nanomedicine 11:447-56

Showing the most recent 10 out of 362 publications