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Sam G, Plain K, Chen S, Islam A, Westman ME, Marsh I, Stenos J, Graves SR, Rehm BHA. Synthetic Particulate Subunit Vaccines for the Prevention of Q Fever. Adv Healthc Mater 2024; 13:e2302351. [PMID: 38198823 DOI: 10.1002/adhm.202302351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 12/10/2023] [Indexed: 01/12/2024]
Abstract
Coxiella burnetti is an intracellular bacterium that causes Q fever, a disease of worldwide importance. Q-VAX® , the approved human Q fever vaccine, is a whole cell vaccine associated with safety concerns. Here a safe particulate subunit vaccine candidate is developed that is ambient-temperature stable and can be cost-effectively manufactured. Endotoxin-free Escherichia coli is bioengineered to efficiently self-assemble biopolymer particles (BPs) that are densely coated with either strings of 18 T-cell epitopes (COX-BP) or two full-length immunodominant antigens (YbgF-BP-Com1) all derived from C. burnetii. BP vaccine candidates are ambient-temperature stable. Safety and immunogenicity are confirmed in mice and guinea pig (GP) models. YbgF-BP-Com1 elicits specific and strong humoral immune responses in GPs with IgG titers that are at least 1 000 times higher than those induced by Q-VAX® . BP vaccine candidates are not reactogenic. After challenge with C. burnetii, YbgF-BP-Com1 vaccine leads to reduced fever responses and pathogen burden in the liver and the induction of proinflammatory cytokines IL-12 and IFN-γ inducible protein (IP-10) when compared to negative control groups. These data suggest that YbgF-BP-Com1 induces functional immune responses reducing infection by C. burnetii. Collectively, these findings illustrate the potential of BPs as effective antigen carrier for Q fever vaccine development.
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Affiliation(s)
- Gayathri Sam
- Centre for Cell Factories and Biopolymers, Griffith Institute for Drug Discovery, Griffith University, Brisbane, QLD, 4111, Australia
| | - Karren Plain
- Elizabeth Macarthur Agricultural Institute, NSW Department of Primary Industries, Menangle, NSW, 2568, Australia
| | - Shuxiong Chen
- Centre for Cell Factories and Biopolymers, Griffith Institute for Drug Discovery, Griffith University, Brisbane, QLD, 4111, Australia
| | - Aminul Islam
- Australian Rickettsial Reference Laboratory, University Hospital, Geelong, VIC, 3220, Australia
| | - Mark E Westman
- Elizabeth Macarthur Agricultural Institute, NSW Department of Primary Industries, Menangle, NSW, 2568, Australia
| | - Ian Marsh
- Elizabeth Macarthur Agricultural Institute, NSW Department of Primary Industries, Menangle, NSW, 2568, Australia
| | - John Stenos
- Australian Rickettsial Reference Laboratory, University Hospital, Geelong, VIC, 3220, Australia
| | - Stephen R Graves
- Elizabeth Macarthur Agricultural Institute, NSW Department of Primary Industries, Menangle, NSW, 2568, Australia
- Australian Rickettsial Reference Laboratory, University Hospital, Geelong, VIC, 3220, Australia
| | - Bernd H A Rehm
- Centre for Cell Factories and Biopolymers, Griffith Institute for Drug Discovery, Griffith University, Brisbane, QLD, 4111, Australia
- Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, 4222, Australia
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2
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Redden P, Parker K, Henderson S, Fourie P, Agnew L, Stenos J, Graves S, Govan B, Norton R, Ketheesan N. Q fever - immune responses and novel vaccine strategies. Future Microbiol 2023; 18:1185-1196. [PMID: 37850346 DOI: 10.2217/fmb-2023-0117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Accepted: 08/07/2023] [Indexed: 10/19/2023] Open
Abstract
Q fever is a zoonotic disease caused by the bacterium Coxiella burnetii. It is an occupational risk for employees of animal industries and is associated with contact with wildlife and domestic animals. Although Q fever infection may be asymptomatic, chronic sequelae such as endocarditis occur in 5% of symptomatic individuals. Disease outcomes may be predicted through measurement of immune correlates. Vaccination is the most efficient method to prevent Q fever. Currently, Q-VAX is the only licenced human vaccine. Q-VAX is highly effective; however, individuals previously exposed to C. burnetii are at risk of adverse reactions. This review examines the immunological responses of acute and chronic Q fever and the efforts to provide a safer and cost-effective Q fever vaccine.
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Affiliation(s)
- Patricia Redden
- School of Science & Technology, University of New England, New South Wales, 2351, Australia
| | - Kaitland Parker
- School of Science & Technology, University of New England, New South Wales, 2351, Australia
| | - Sinead Henderson
- School of Science & Technology, University of New England, New South Wales, 2351, Australia
| | - Phillip Fourie
- School of Science & Technology, University of New England, New South Wales, 2351, Australia
| | - Linda Agnew
- School of Science & Technology, University of New England, New South Wales, 2351, Australia
- Griffith Health Group, Griffith University, Queensland, 4222, Australia
| | - John Stenos
- Australian Rickettsial Reference Laboratory, Barwon Health, Geelong, Victoria, 3220, Australia
| | - Stephen Graves
- Australian Rickettsial Reference Laboratory, Barwon Health, Geelong, Victoria, 3220, Australia
| | - Brenda Govan
- College of Public Health, Medicine & Vet Sciences, James Cook University, Queensland, 4811, Australia
| | - Robert Norton
- Pathology Queensland, Queensland Health, Townsville Hospital, Queensland, 4814, Australia
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, 4072, Australia
| | - Natkunam Ketheesan
- School of Science & Technology, University of New England, New South Wales, 2351, Australia
- Griffith Health Group, Griffith University, Queensland, 4222, Australia
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3
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Bach E, Fitzgerald SF, Williams-MacDonald SE, Mitchell M, Golde WT, Longbottom D, Nisbet AJ, Dinkla A, Sullivan E, Pinapati RS, Tan JC, Joosten LAB, Roest HJ, Østerbye T, Koets AP, Buus S, McNeilly TN. Genome-wide epitope mapping across multiple host species reveals significant diversity in antibody responses to Coxiella burnetii vaccination and infection. Front Immunol 2023; 14:1257722. [PMID: 37954609 PMCID: PMC10637584 DOI: 10.3389/fimmu.2023.1257722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 09/19/2023] [Indexed: 11/14/2023] Open
Abstract
Coxiella burnetii is an important zoonotic bacterial pathogen of global importance, causing the disease Q fever in a wide range of animal hosts. Ruminant livestock, in particular sheep and goats, are considered the main reservoir of human infection. Vaccination is a key control measure, and two commercial vaccines based on formalin-inactivated C. burnetii bacterins are currently available for use in livestock and humans. However, their deployment is limited due to significant reactogenicity in individuals previously sensitized to C. burnetii antigens. Furthermore, these vaccines interfere with available serodiagnostic tests which are also based on C. burnetii bacterin antigens. Defined subunit antigen vaccines offer significant advantages, as they can be engineered to reduce reactogenicity and co-designed with serodiagnostic tests to allow discrimination between vaccinated and infected individuals. This study aimed to investigate the diversity of antibody responses to C. burnetii vaccination and/or infection in cattle, goats, humans, and sheep through genome-wide linear epitope mapping to identify candidate vaccine and diagnostic antigens within the predicted bacterial proteome. Using high-density peptide microarrays, we analyzed the seroreactivity in 156 serum samples from vaccinated and infected individuals to peptides derived from 2,092 open-reading frames in the C. burnetii genome. We found significant diversity in the antibody responses within and between species and across different types of C. burnetii exposure. Through the implementation of three different vaccine candidate selection methods, we identified 493 candidate protein antigens for protein subunit vaccine design or serodiagnostic evaluation, of which 65 have been previously described. This is the first study to investigate multi-species seroreactivity against the entire C. burnetii proteome presented as overlapping linear peptides and provides the basis for the selection of antigen targets for next-generation Q fever vaccines and diagnostic tests.
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Affiliation(s)
- Emil Bach
- Department of Immunology & Microbiology, University of Copenhagen, Copenhagen, Denmark
| | | | | | | | | | | | | | - Annemieke Dinkla
- Department of Bacteriology, Host-Pathogen Interaction and Diagnostic Development, Wageningen Bioveterinary Research, Lelystad, Netherlands
| | - Eric Sullivan
- Nimble Therapeutics, Inc., Madison, WI, United States
| | | | - John C. Tan
- Nimble Therapeutics, Inc., Madison, WI, United States
| | - Leo A. B. Joosten
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Hendrik-Jan Roest
- Department of Bacteriology, Host-Pathogen Interaction and Diagnostic Development, Wageningen Bioveterinary Research, Lelystad, Netherlands
- Ministry of Agriculture, Nature and Food Quality, Den Haag, Netherlands
- Department of Infection and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Thomas Østerbye
- Department of Immunology & Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Ad P. Koets
- Department of Bacteriology, Host-Pathogen Interaction and Diagnostic Development, Wageningen Bioveterinary Research, Lelystad, Netherlands
| | - Søren Buus
- Department of Immunology & Microbiology, University of Copenhagen, Copenhagen, Denmark
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4
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Ramirez A, Felgner J, Jain A, Jan S, Albin TJ, Badten AJ, Gregory AE, Nakajima R, Jasinskas A, Felgner PL, Burkhardt AM, Davies DH, Wang SW. Engineering Protein Nanoparticles Functionalized with an Immunodominant Coxiella burnetii Antigen to Generate a Q Fever Vaccine. Bioconjug Chem 2023; 34:1653-1666. [PMID: 37682243 PMCID: PMC10515490 DOI: 10.1021/acs.bioconjchem.3c00317] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 08/25/2023] [Indexed: 09/09/2023]
Abstract
Coxiella burnetii is the causative agent of Q fever, for which there is yet to be an FDA-approved vaccine. This bacterial pathogen has both extra- and intracellular stages in its life cycle, and therefore both a cell-mediated (i.e., T lymphocyte) and humoral (i.e., antibody) immune response are necessary for effective eradication of this pathogen. However, most proposed vaccines elicit strong responses to only one mechanism of adaptive immunity, and some can either cause reactogenicity or lack sufficient immunogenicity. In this work, we aim to apply a nanoparticle-based platform toward producing both antibody and T cell immune responses against C. burnetii. We investigated three approaches for conjugation of the immunodominant outer membrane protein antigen (CBU1910) to the E2 nanoparticle to obtain a consistent antigen orientation: direct genetic fusion, high affinity tris-NTA-Ni conjugation to polyhistidine-tagged CBU1910, and the SpyTag/SpyCatcher (ST/SC) system. Overall, we found that the ST/SC approach yielded nanoparticles loaded with the highest number of antigens while maintaining stability, enabling formulations that could simultaneously co-deliver the protein antigen (CBU1910) and adjuvant (CpG1826) on one nanoparticle (CBU1910-CpG-E2). Using protein microarray analyses, we found that after immunization, antigen-bound nanoparticle formulations elicited significantly higher antigen-specific IgG responses than soluble CBU1910 alone and produced more balanced IgG1/IgG2c ratios. Although T cell recall assays from these protein antigen formulations did not show significant increases in antigen-specific IFN-γ production compared to soluble CBU1910 alone, nanoparticles conjugated with a CD4 peptide epitope from CBU1910 generated elevated T cell responses in mice to both the CBU1910 peptide epitope and whole CBU1910 protein. These investigations highlight the feasibility of conjugating antigens to nanoparticles for tuning and improving both humoral- and cell-mediated adaptive immunity against C. burnetii.
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Affiliation(s)
- Aaron Ramirez
- Department
of Chemical and Biomolecular Engineering, Vaccine Research and Development
Center, Department of Physiology and Biophysics, Department of Chemistry, Department of Biomedical
Engineering, Chao Family Comprehensive Cancer Center, and Institute for Immunology, University of California, Irvine, California 92697, United States
| | - Jiin Felgner
- Department
of Chemical and Biomolecular Engineering, Vaccine Research and Development
Center, Department of Physiology and Biophysics, Department of Chemistry, Department of Biomedical
Engineering, Chao Family Comprehensive Cancer Center, and Institute for Immunology, University of California, Irvine, California 92697, United States
| | - Aarti Jain
- Department
of Chemical and Biomolecular Engineering, Vaccine Research and Development
Center, Department of Physiology and Biophysics, Department of Chemistry, Department of Biomedical
Engineering, Chao Family Comprehensive Cancer Center, and Institute for Immunology, University of California, Irvine, California 92697, United States
| | - Sharon Jan
- Department
of Chemical and Biomolecular Engineering, Vaccine Research and Development
Center, Department of Physiology and Biophysics, Department of Chemistry, Department of Biomedical
Engineering, Chao Family Comprehensive Cancer Center, and Institute for Immunology, University of California, Irvine, California 92697, United States
| | - Tyler J. Albin
- Department
of Chemical and Biomolecular Engineering, Vaccine Research and Development
Center, Department of Physiology and Biophysics, Department of Chemistry, Department of Biomedical
Engineering, Chao Family Comprehensive Cancer Center, and Institute for Immunology, University of California, Irvine, California 92697, United States
| | - Alexander J. Badten
- Department
of Chemical and Biomolecular Engineering, Vaccine Research and Development
Center, Department of Physiology and Biophysics, Department of Chemistry, Department of Biomedical
Engineering, Chao Family Comprehensive Cancer Center, and Institute for Immunology, University of California, Irvine, California 92697, United States
| | - Anthony E. Gregory
- Department
of Chemical and Biomolecular Engineering, Vaccine Research and Development
Center, Department of Physiology and Biophysics, Department of Chemistry, Department of Biomedical
Engineering, Chao Family Comprehensive Cancer Center, and Institute for Immunology, University of California, Irvine, California 92697, United States
| | - Rie Nakajima
- Department
of Chemical and Biomolecular Engineering, Vaccine Research and Development
Center, Department of Physiology and Biophysics, Department of Chemistry, Department of Biomedical
Engineering, Chao Family Comprehensive Cancer Center, and Institute for Immunology, University of California, Irvine, California 92697, United States
| | - Algimantas Jasinskas
- Department
of Chemical and Biomolecular Engineering, Vaccine Research and Development
Center, Department of Physiology and Biophysics, Department of Chemistry, Department of Biomedical
Engineering, Chao Family Comprehensive Cancer Center, and Institute for Immunology, University of California, Irvine, California 92697, United States
| | - Philip L. Felgner
- Department
of Chemical and Biomolecular Engineering, Vaccine Research and Development
Center, Department of Physiology and Biophysics, Department of Chemistry, Department of Biomedical
Engineering, Chao Family Comprehensive Cancer Center, and Institute for Immunology, University of California, Irvine, California 92697, United States
| | - Amanda M. Burkhardt
- Department
of Clinical Pharmacy, School of Pharmacy, University of Southern California, Los Angeles, California 90089, United States
| | - D. Huw Davies
- Department
of Chemical and Biomolecular Engineering, Vaccine Research and Development
Center, Department of Physiology and Biophysics, Department of Chemistry, Department of Biomedical
Engineering, Chao Family Comprehensive Cancer Center, and Institute for Immunology, University of California, Irvine, California 92697, United States
| | - Szu-Wen Wang
- Department
of Chemical and Biomolecular Engineering, Vaccine Research and Development
Center, Department of Physiology and Biophysics, Department of Chemistry, Department of Biomedical
Engineering, Chao Family Comprehensive Cancer Center, and Institute for Immunology, University of California, Irvine, California 92697, United States
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5
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Charles T, Moss DL, Bhat P, Moore PW, Kummer NA, Bhattacharya A, Landry SJ, Mettu RR. CD4+ T-Cell Epitope Prediction by Combined Analysis of Antigen Conformational Flexibility and Peptide-MHCII Binding Affinity. Biochemistry 2022; 61:1585-1599. [PMID: 35834502 PMCID: PMC9352311 DOI: 10.1021/acs.biochem.2c00237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Antigen processing in the class II MHC pathway depends
on conventional
proteolytic enzymes, potentially acting on antigens in native-like
conformational states. CD4+ epitope dominance arises from a competition
among antigen folding, proteolysis, and MHCII binding. Protease-sensitive
sites, linear antibody epitopes, and CD4+ T-cell epitopes were mapped
in plague vaccine candidate F1-V to evaluate the various contributions
to CD4+ epitope dominance. Using X-ray crystal structures, antigen
processing likelihood (APL) predicts CD4+ epitopes with significant
accuracy for F1-V without considering peptide-MHCII binding affinity.
We also show that APL achieves excellent performance over two benchmark
antigen sets. The profiles of conformational flexibility derived from
the X-ray crystal structures of the F1-V proteins, Caf1 and LcrV,
were similar to the biochemical profiles of linear antibody epitope
reactivity and protease sensitivity, suggesting that the role of structure
in proteolysis was captured by the analysis of the crystal structures.
The patterns of CD4+ T-cell epitope dominance in C57BL/6, CBA, and
BALB/c mice were compared to epitope predictions based on APL, MHCII
binding, or both. For a sample of 13 diverse antigens, the accuracy
of epitope prediction by the combination of APL and I-Ab-MHCII-peptide affinity reached 36%. When MHCII allele specificity
was also diverse, such as in human immunity, prediction of dominant
epitopes by APL alone reached 42% when using a stringent scoring threshold.
Because dominant CD4+ epitopes tend to occur in conformationally stable
antigen domains, crystal structures typically are available for analysis
by APL, and thus, the requirement for a crystal structure is not a
severe limitation.
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Affiliation(s)
- Tysheena Charles
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Daniel L Moss
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Pawan Bhat
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Peyton W Moore
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Nicholas A Kummer
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Avik Bhattacharya
- Department of Computer Science, Tulane University, New Orleans, Louisiana 70118, United States
| | - Samuel J Landry
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Ramgopal R Mettu
- Department of Computer Science, Tulane University, New Orleans, Louisiana 70118, United States
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6
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Gregory AE, van Schaik EJ, Fratzke AP, Russell-Lodrigue KE, Farris CM, Samuel JE. Soluble antigens derived from Coxiella burnetii elicit protective immunity in three animal models without inducing hypersensitivity. Cell Rep Med 2021; 2:100461. [PMID: 35028605 PMCID: PMC8714860 DOI: 10.1016/j.xcrm.2021.100461] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 09/27/2021] [Accepted: 11/10/2021] [Indexed: 11/25/2022]
Abstract
Q fever is caused by the intracellular bacterium Coxiella burnetii, for which there is no approved vaccine in the United States. A formalin-inactivated whole-cell vaccine (WCV) from virulent C. burnetii NMI provides single-dose long-lived protection, but concerns remain over vaccine reactogenicity. We therefore sought an alternate approach by purifying native C. burnetii antigens from the clonally derived avirulent NMII strain. A soluble bacterial extract, termed Sol II, elicits high-titer, high-avidity antibodies and induces a CD4 T cell response that confers protection in naive mice. In addition, Sol II protects against pulmonary C. burnetii challenge in three animal models without inducing hypersensitivity. An NMI-derived extract, Sol I, enhances protection further and outperforms the WCV gold standard. Collectively, these data represent a promising approach to design highly effective, non-reactogenic Q fever vaccines.
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Affiliation(s)
- Anthony E. Gregory
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Medical Research and Education Building, Bryan, TX 77807, USA
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA 92617, USA
| | - Erin J. van Schaik
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Medical Research and Education Building, Bryan, TX 77807, USA
| | - Alycia P. Fratzke
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Medical Research and Education Building, Bryan, TX 77807, USA
| | - Kasi E. Russell-Lodrigue
- Tulane University, School of Medicine, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Christina M. Farris
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Medical Research and Education Building, Bryan, TX 77807, USA
| | - James E. Samuel
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Medical Research and Education Building, Bryan, TX 77807, USA
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7
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Piel LMW, Durfee CJ, White SN. Proteome-wide analysis of Coxiella burnetii for conserved T-cell epitopes with presentation across multiple host species. BMC Bioinformatics 2021; 22:296. [PMID: 34078271 PMCID: PMC8170629 DOI: 10.1186/s12859-021-04181-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 05/10/2021] [Indexed: 12/29/2022] Open
Abstract
Background Coxiella burnetii is the Gram-negative bacterium responsible for Q fever in humans and coxiellosis in domesticated agricultural animals. Previous vaccination efforts with whole cell inactivated bacteria or surface isolated proteins confer protection but can produce a reactogenic immune responses. Thereby a protective vaccine that does not cause aberrant immune reactions is required. The critical role of T-cell immunity in control of C. burnetii has been made clear, since either CD8+ or CD4+ T cells can empower clearance. The purpose of this study was to identify C. burnetii proteins bearing epitopes that interact with major histocompatibility complexes (MHC) from multiple host species (human, mouse, and cattle). Results Of the annotated 1815 proteins from the Nine Mile Phase I (RSA 493) assembly, 402 proteins were removed from analysis due to a lack of inter-isolate conservation. An additional 391 proteins were eliminated from assessment to avoid potential autoimmune responses due to the presence of host homology. We analyzed the remaining 1022 proteins for their ability to produce peptides that bind MHCI or MHCII. MHCI and MHCII predicted epitopes were filtered and compared between species yielding 777 MHCI epitopes and 453 MHCII epitopes. These epitopes were further examined for presentation by both MHCI and MHCII, and for proteins that contained multiple epitopes. There were 31 epitopes that overlapped positionally between MHCI and MHCII across host species. Of these, there were 9 epitopes represented within proteins containing ≥ 5 total epitopes, where an additional 24 proteins were also epitope dense. In all, 55 proteins were found to contain high scoring T-cell epitopes. Besides the well-studied protein Com1, most identified proteins were novel when compared to previously studied vaccine candidates. Conclusion These data represent the first proteome-wide evaluation of C. burnetii peptide epitopes. Furthermore, the inclusion of human, mouse, and bovine data capture a range of hosts for this zoonotic pathogen plus an important model organism. This work provides new vaccine targets for future vaccination efforts and enhances opportunities for selecting multiple T-cell epitope types to include within a vaccine. Supplementary Information The online version contains supplementary material available at 10.1186/s12859-021-04181-w.
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Affiliation(s)
| | - Codie J Durfee
- USDA-ARS Animal Disease Research Unit, Pullman, WA, 99164, USA
| | - Stephen N White
- USDA-ARS Animal Disease Research Unit, Pullman, WA, 99164, USA. .,Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, 99164, USA. .,Center for Reproductive Biology, Washington State University, Pullman, WA, 99164, USA.
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8
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Miller HK, Kersh GJ. Analysis of recombinant proteins for Q fever diagnostics. Sci Rep 2020; 10:20934. [PMID: 33262373 PMCID: PMC7708433 DOI: 10.1038/s41598-020-77343-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 11/06/2020] [Indexed: 11/20/2022] Open
Abstract
Serology is essential for Q fever diagnostics, a disease caused by the bacterial pathogen Coxiella burnetii. The gold standard test is an immunofluorescence assay utilizing whole cell antigens, which are both dangerous and laborious to produce. Complexities of the antigen coupled with the subjective nature of the assay lead to decreased uniformity of test results and underscore the need for improved methodologies. Thirty-three C. burnetii proteins, previously identified as immunoreactive, were screened for reactivity to naturally infected goat serum. Based on reactivity, 10 proteins were analyzed in a secondary screen against human serum from healthy donors. Assay sensitivity and specificity ranged from 21 to 71% and 90 to 100%, respectively. Three promising antigens were identified based on receiver operating characteristic curve analysis (CBU_1718, CBU_0307, and CBU_1398). Five multiplex assays failed to outperform the individual proteins, with sensitivities and specificities ranging from 29 to 57% and 90 to 100%, respectively. Truncating the top antigen, CBU_1718, had no effect on specificity (90%); yet sensitivity decreased dramatically (71% to 21%). Through this study, we have expanded the subset of C. burnetii immunoreactive proteins validated by enzyme-linked immunosorbent assay and demonstrate the effect of novel antigen combinations and protein truncations on assay performance.
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Affiliation(s)
- Halie K Miller
- Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - Gilbert J Kersh
- Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, GA, USA
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9
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Coxiella burnetii-Infected NK Cells Release Infectious Bacteria by Degranulation. Infect Immun 2020; 88:IAI.00172-20. [PMID: 32817330 DOI: 10.1128/iai.00172-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Accepted: 08/10/2020] [Indexed: 01/24/2023] Open
Abstract
Natural killer (NK) cells are critically involved in the early immune response against various intracellular pathogens, including Coxiella burnetii and Chlamydia psittaci Chlamydia-infected NK cells functionally mature, induce cellular immunity, and protect themselves by killing the bacteria in secreted granules. Here, we report that infected NK cells do not allow intracellular multiday growth of Coxiella, as is usually observed in other host cell types. C. burnetii-infected NK cells display maturation and gamma interferon (IFN-γ) secretion, as well as the release of Coxiella-containing lytic granules. Thus, NK cells possess a potent program to restrain and expel different types of invading bacteria via degranulation. Strikingly, though, in contrast to Chlamydia, expulsed Coxiella organisms largely retain their infectivity and, hence, escape the cell-autonomous self-defense mechanism in NK cells.
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10
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Reeves PM, Raju Paul S, Baeten L, Korek SE, Yi Y, Hess J, Sobell D, Scholzen A, Garritsen A, De Groot AS, Moise L, Brauns T, Bowen R, Sluder AE, Poznansky MC. Novel multiparameter correlates of Coxiella burnetii infection and vaccination identified by longitudinal deep immune profiling. Sci Rep 2020; 10:13311. [PMID: 32770104 PMCID: PMC7414860 DOI: 10.1038/s41598-020-69327-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 06/05/2020] [Indexed: 12/12/2022] Open
Abstract
Q-fever is a flu-like illness caused by Coxiella burnetii (Cb), a highly infectious intracellular bacterium. There is an unmet need for a safe and effective vaccine for Q-fever. Correlates of immune protection to Cb infection are limited. We proposed that analysis by longitudinal high dimensional immune (HDI) profiling using mass cytometry combined with other measures of vaccination and protection could be used to identify novel correlates of effective vaccination and control of Cb infection. Using a vaccine-challenge model in HLA-DR transgenic mice, we demonstrated significant alterations in circulating T-cell and innate immune populations that distinguished vaccinated from naïve mice within 10 days, and persisted until at least 35 days post-vaccination. Following challenge, vaccinated mice exhibited reduced bacterial burden and splenomegaly, along with distinct effector T-cell and monocyte profiles. Correlation of HDI data to serological and pathological measurements was performed. Our data indicate a Th1-biased response to Cb, consistent with previous reports, and identify Ly6C, CD73, and T-bet expression in T-cell, NK-cell, and monocytic populations as distinguishing features between vaccinated and naïve mice. This study refines the understanding of the integrated immune response to Cb vaccine and challenge, which can inform the assessment of candidate vaccines for Cb.
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Affiliation(s)
- P M Reeves
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, USA.
| | - S Raju Paul
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, USA
| | - L Baeten
- Colorado State University, Fort Collins, CO, USA
| | - S E Korek
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, USA
| | - Y Yi
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, USA
| | - J Hess
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, USA
| | - D Sobell
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, USA
| | - A Scholzen
- InnatOss Laboratories B.V, Oss, The Netherlands
| | - A Garritsen
- InnatOss Laboratories B.V, Oss, The Netherlands
| | - A S De Groot
- EpiVax, Inc, Providence, RI, USA.,Center for Vaccines and Immunology, University of Georgia, Athens, GA, USA
| | - L Moise
- EpiVax, Inc, Providence, RI, USA.,Institute for Immunology and Informatics, Department of Cell and Molecular Biology, University of Rhode Island, Providence, RI, USA
| | - T Brauns
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, USA
| | - R Bowen
- Colorado State University, Fort Collins, CO, USA
| | - A E Sluder
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, USA
| | - M C Poznansky
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, USA.
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11
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Scholzen A, Richard G, Moise L, Baeten LA, Reeves PM, Martin WD, Brauns TA, Boyle CM, Raju Paul S, Bucala R, Bowen RA, Garritsen A, De Groot AS, Sluder AE, Poznansky MC. Promiscuous Coxiella burnetii CD4 Epitope Clusters Associated With Human Recall Responses Are Candidates for a Novel T-Cell Targeted Multi-Epitope Q Fever Vaccine. Front Immunol 2019; 10:207. [PMID: 30828331 PMCID: PMC6384241 DOI: 10.3389/fimmu.2019.00207] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 01/23/2019] [Indexed: 12/13/2022] Open
Abstract
Coxiella burnetii, the causative agent of Q fever, is a Gram-negative intracellular bacterium transmitted via aerosol. Regulatory approval of the Australian whole-cell vaccine Q-VAX® in the US and Europe is hindered by reactogenicity in previously exposed individuals. The aim of this study was to identify and rationally select C. burnetii epitopes for design of a safe, effective, and less reactogenic T-cell targeted human Q fever vaccine. Immunoinformatic methods were used to predict 65 HLA class I epitopes and 50 promiscuous HLA class II C. burnetii epitope clusters, which are conserved across strains of C. burnetii. HLA binding assays confirmed 89% of class I and 75% of class II predictions, and 11 HLA class II epitopes elicited IFNγ responses following heterologous DNA/DNA/peptide/peptide prime-boost immunizations of HLA-DR3 transgenic mice. Human immune responses to the predicted epitopes were characterized in individuals naturally exposed to C. burnetii during the 2007–2010 Dutch Q fever outbreak. Subjects were divided into three groups: controls with no immunological evidence of previous infection and individuals with responses to heat-killed C. burnetii in a whole blood IFNγ release assay (IGRA) who remained asymptomatic or who experienced clinical Q fever during the outbreak. Recall responses to C. burnetii epitopes were assessed by cultured IFNγ ELISpot. While HLA class I epitope responses were sparse in this cohort, we identified 21 HLA class II epitopes that recalled T-cell IFNγ responses in 10–28% of IGRA+ subjects. IGRA+ individuals with past asymptomatic and symptomatic C. burnetii infection showed a comparable response pattern and cumulative peptide response which correlated with IGRA responses. None of the peptides elicited reactogenicity in a C. burnetii exposure-primed guinea pig model. These data demonstrate that a substantial proportion of immunoinformatically identified HLA class II epitopes show long-lived immunoreactivity in naturally infected individuals, making them desirable candidates for a novel human multi-epitope Q fever vaccine.
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Affiliation(s)
| | | | - Leonard Moise
- EpiVax, Inc., Providence, RI, United States.,Department of Cell and Molecular Biology, Institute for Immunology and Informatics, University of Rhode Island, Providence, RI, United States
| | - Laurie A Baeten
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, United States
| | - Patrick M Reeves
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, United States
| | | | - Timothy A Brauns
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, United States
| | | | - Susan Raju Paul
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, United States
| | - Richard Bucala
- Department of Medicine, Yale University School of Medicine, New Haven, CT, United States
| | - Richard A Bowen
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, United States
| | | | - Anne S De Groot
- EpiVax, Inc., Providence, RI, United States.,Department of Cell and Molecular Biology, Institute for Immunology and Informatics, University of Rhode Island, Providence, RI, United States
| | - Ann E Sluder
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, United States
| | - Mark C Poznansky
- Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, MA, United States
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12
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Wang P, Xiong X, Jiao J, Yang X, Jiang Y, Wen B, Gong W. Th1 epitope peptides induce protective immunity against Rickettsia rickettsii infection in C3H/HeN mice. Vaccine 2017; 35:7204-7212. [PMID: 29032899 DOI: 10.1016/j.vaccine.2017.09.068] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 09/01/2017] [Accepted: 09/22/2017] [Indexed: 10/18/2022]
Abstract
Rickettsia rickettsii is the causative pathogen of Rocky Mountain spotted fever (RMSF). Adr2, YbgF and OmpB are protective antigens of R. rickettsii. In this study, 90 candidate peptides were selected from these antigens based on their high-affinity binding capacity for the MHC class II molecule H2 I-A or H2 I-E using bioinformatic methods. Six peptides were determined using ELISPOT assay to be immunodominant based on the IFN-γ recall responses of CD4+ T cells from mice immunized with R. rickettsii. Six nucleotide sequences encoding the immunodominant peptides were linked in series and inserted into a plasmid for expression in Escherichia coli cells, resulting in a new, recombinant polypeptide termed GWP. After immunization and challenge, the rickettsial load or histopathological lesions in the organs of mice immunized with GWP or pooled peptides was significantly lower than that in organs of mice immunized with PBS or the individual peptide OmpB399. An in vitro neutralization test revealed that sera from mice immunized with GWP, OmpB399, or pooled peptides reduced R. rickettsii adherence to, and invasion of, vascular endothelial cells. Furthermore, significantly higher levels of IgG, IgG1, or IgG2a were detected in sera from mice immunized with GWP or pooled peptides, and significantly higher levels of IFN-γ or TNF-α secreted by CD4+ T cells from R. rickettsii-infected mice were detected after immunization with GWP. Altogether, our results indicated that polypeptides, especially GWP, could induce a Th1-type immune response against R. rickettsii infection, which might contribute to the rational design of peptide-based vaccines for RMSF.
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Affiliation(s)
- Pengcheng Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, 20# Dong-Dia-Jie Street, Fengtai, Beijing 100071, China
| | - Xiaolu Xiong
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, 20# Dong-Dia-Jie Street, Fengtai, Beijing 100071, China
| | - Jun Jiao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, 20# Dong-Dia-Jie Street, Fengtai, Beijing 100071, China
| | - Xiaomei Yang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, 20# Dong-Dia-Jie Street, Fengtai, Beijing 100071, China
| | - Yongqiang Jiang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, 20# Dong-Dia-Jie Street, Fengtai, Beijing 100071, China
| | - Bohai Wen
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, 20# Dong-Dia-Jie Street, Fengtai, Beijing 100071, China
| | - Wenping Gong
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, 20# Dong-Dia-Jie Street, Fengtai, Beijing 100071, China; Army Tuberculosis Prevention and Control Key Laboratory/Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research, The 309th Hospital of Chinese PLA, 17# Hei-Shan-Hu Road, Haidian, Beijing 100091, China.
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13
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Reeves PM, Paul SR, Sluder AE, Brauns TA, Poznansky MC. Q-vaxcelerate: A distributed development approach for a new Coxiella burnetii vaccine. Hum Vaccin Immunother 2017; 13:2977-2981. [PMID: 28933682 PMCID: PMC5718828 DOI: 10.1080/21645515.2017.1371377] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Development of vaccines that are both safe and effective remains a costly and time-consuming challenge. To accelerate the pace of development and improve the efficacy and safety of candidate vaccines for both existing and emerging infectious agents, we have used a distributed development approach. This features the managed integration of individual expert groups having the requisite vaccine platforms, pre-clinical models, assays, skills and knowledge pertinent to a specific pathogen into a single, end-to-end development team capable of producing a new vaccine tailored to that particular agent. Distributed development focuses on integrating existing effort across multiple institutions rather than developing new capabilities or consolidating resources within an individual organization. Previously we have used the distributed development strategy to generate vaccine candidates for emerging viral diseases. Coxiella burnetii is a highly infectious and resilient bacterium and the causative agent of Q fever. Treatment for Q fever can require months of antibiotics. The current vaccine for Q-fever is only approved in Australia and requires prescreening due to the potential for severe reactogenicity in previously exposed individuals. Here we discuss Q-VaxCelerate, a distributed development consortium for the development of a new vaccine to prevent Q fever.
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Affiliation(s)
- Patrick M Reeves
- a Vaccine and Immunotherapy Center, Division of Infectious Diseases, Department of Medicine , Massachusetts General Hospital , Boston , MA , USA
| | - Susan Raju Paul
- a Vaccine and Immunotherapy Center, Division of Infectious Diseases, Department of Medicine , Massachusetts General Hospital , Boston , MA , USA
| | - Ann E Sluder
- a Vaccine and Immunotherapy Center, Division of Infectious Diseases, Department of Medicine , Massachusetts General Hospital , Boston , MA , USA
| | - Timothy A Brauns
- a Vaccine and Immunotherapy Center, Division of Infectious Diseases, Department of Medicine , Massachusetts General Hospital , Boston , MA , USA
| | - Mark C Poznansky
- a Vaccine and Immunotherapy Center, Division of Infectious Diseases, Department of Medicine , Massachusetts General Hospital , Boston , MA , USA
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14
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Xiong X, Jiao J, Gregory AE, Wang P, Bi Y, Wang X, Jiang Y, Wen B, Portnoy DA, Samuel JE, Chen C. Identification of Coxiella burnetii CD8+ T-Cell Epitopes and Delivery by Attenuated Listeria monocytogenes as a Vaccine Vector in a C57BL/6 Mouse Model. J Infect Dis 2017; 215:1580-1589. [PMID: 27703037 DOI: 10.1093/infdis/jiw470] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 09/25/2016] [Indexed: 01/26/2023] Open
Abstract
Coxiella burnetii is a gram-negative bacterium that causes acute and chronic Q fever. Because of the severe adverse effect of whole-cell vaccination, identification of immunodominant antigens of C. burnetii has become a major focus of Q fever vaccine development. We hypothesized that secreted C. burnetii type IV secretion system (T4SS) effectors may represent a major class of CD8+ T-cell antigens, owing to their cytosolic localization. Twenty-nine peptides were identified that elicited robust CD8+ T-cell interferon γ (IFN-γ) recall responses from mice infected with C. burnetii. Interestingly, 22 of 29 epitopes were derived from 17 T4SS-related proteins, none of which were identified as immunodominant antigens by using previous antibody-guided approaches. These epitopes were expressed in an attenuated Listeria monocytogenes vaccine strain. Immunization with recombinant L. monocytogenes vaccines induced a robust CD8+ T-cell response and conferred measurable protection against C. burnetii infection in mice. These data suggested that T4SS effectors represent an important class of C. burnetii antigens that can induce CD8+ T-cell responses. We also showed that attenuated L. monocytogenes vaccine vectors are an efficient antigen-delivery platform that can be used to induce robust protective CD8+ T-cell immune responses against C. burnetii infection.
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Affiliation(s)
- Xiaolu Xiong
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology
| | - Jun Jiao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology
| | - Anthony E Gregory
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan
| | - Pengcheng Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology.,Department of Clinical Laboratory, 105th Hospital of the People's Liberation Army, Hefei, China
| | - Yujing Bi
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology
| | - Xiaoyi Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology
| | - Yongqiang Jiang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology
| | - Bohai Wen
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology
| | - Daniel A Portnoy
- Department of Molecular and Cell Biology, University of California, Berkeley
| | - James E Samuel
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan
| | - Chen Chen
- Department of Molecular and Cell Biology, University of California, Berkeley
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15
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In silico analysis to identify vaccine candidates common to multiple serotypes of Shigella and evaluation of their immunogenicity. PLoS One 2017; 12:e0180505. [PMID: 28767653 PMCID: PMC5540609 DOI: 10.1371/journal.pone.0180505] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 06/18/2017] [Indexed: 12/20/2022] Open
Abstract
Shigellosis or bacillary dysentery is an important cause of diarrhea, with the majority of the cases occurring in developing countries. Considering the high disease burden, increasing antibiotic resistance, serotype-specific immunity and the post-infectious sequelae associated with shigellosis, there is a pressing need of an effective vaccine against multiple serotypes of the pathogen. In the present study, we used bio-informatics approach to identify antigens shared among multiple serotypes of Shigella spp. This approach led to the identification of many immunogenic peptides. The five most promising peptides based on MHC binding efficiency were a putative lipoprotein (EL PGI I), a putative heat shock protein (EL PGI II), Spa32 (EL PGI III), IcsB (EL PGI IV) and a hypothetical protein (EL PGI V). These peptides were synthesized and the immunogenicity was evaluated in BALB/c mice by ELISA and cytokine assays. The putative heat shock protein (HSP) and the hypothetical protein elicited good humoral response, whereas putative lipoprotein, Spa32 and IcsB elicited good T-cell response as revealed by increased IFN-γ and TNF-α cytokine levels. The patient sera from confirmed cases of shigellosis were also evaluated for the presence of peptide specific antibodies with significant IgG and IgA antibodies against the HSP and the hypothetical protein, bestowing them as potential future vaccine candidates. The antigens reported in this study are novel and have not been tested as vaccine candidates against Shigella. This study offers time and cost-effective way of identifying unprecedented immunogenic antigens to be used as potential vaccine candidates. Moreover, this approach should easily be extendable to find new potential vaccine candidates for other pathogenic bacteria.
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16
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17
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Merino KM, Bansal GP, Kumar N. Reduced immunogenicity of Plasmodium falciparum gamete surface antigen (Pfs48/45) in mice after disruption of disulphide bonds - evaluating effect of interferon-γ-inducible lysosomal thiol reductase. Immunology 2016; 148:433-47. [PMID: 27177843 PMCID: PMC4948042 DOI: 10.1111/imm.12621] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 05/04/2016] [Accepted: 05/06/2016] [Indexed: 12/16/2022] Open
Abstract
Sexual stages of Plasmodium are critical for malaria transmission and stage-specific antigens are important targets for development of malaria transmission-blocking vaccines. Plasmodium falciparum gamete surface antigen (Pfs48/45) is important for male gamete fertility and is being pursued as a candidate vaccine antigen. Vaccine-induced transmission-blocking antibodies recognize reduction-sensitive conformational epitopes in Pfs48/45. Processing and presentation of such disulphide-bond-constrained epitopes is critical for eliciting the desired immune responses. Mice lacking interferon-γ-inducible lysosomal thiol reductase (GILT), an enzyme that mediates reduction of S-S bonds during antigen processing, were employed to investigate immunogenicity of Pfs48/45. It has been well established that the ability to reduce S-S bonds in antigens guides effective T-cell immune responses; however, involvement of GILT in the induction of subsequent B-cell responses has not been explored. We hypothesized that the ability to reduce S-S bonds in Pfs48/45 will impact the generation of T-cell epitopes, and so influence helper T-cell responses required for specific B-cell responses. Non-reduced and reduced and alkylated forms of Pfs48/45 were employed to evaluate immune responses in wild-type and GILT knockout mice and studies revealed important differences in several immune response parameters, including differences in putative T-cell epitope recognition, faster kinetics of waning of Pfs48/45-specific IgG1 antibodies in knockout mice, differential patterns of interferon-γ and interleukin-4 secretions by splenocytes, and possible effects of GILT on induction of long-lived plasma cells and memory B cells responsible for antigen-recall responses. These studies emphasize the importance of antigen structural features that significantly influence the development of effective immune responses.
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Affiliation(s)
- Kristen M. Merino
- Department of Tropical MedicineSchool of Public Health and Tropical MedicineVector‐borne Infectious Disease Research CenterTulane UniversityNew OrleansLAUSA
| | - Geetha P. Bansal
- Department of Tropical MedicineSchool of Public Health and Tropical MedicineVector‐borne Infectious Disease Research CenterTulane UniversityNew OrleansLAUSA
| | - Nirbhay Kumar
- Department of Tropical MedicineSchool of Public Health and Tropical MedicineVector‐borne Infectious Disease Research CenterTulane UniversityNew OrleansLAUSA
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18
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Longhi SA, Atienza A, Perez Prados G, Buying A, Balouz V, Buscaglia CA, Santos R, Tasso LM, Bonato R, Chiale P, Pinilla C, Judkowski VA, Gómez KA. Cytokine production but lack of proliferation in peripheral blood mononuclear cells from chronic Chagas' disease cardiomyopathy patients in response to T. cruzi ribosomal P proteins. PLoS Negl Trop Dis 2014; 8:e2906. [PMID: 24901991 PMCID: PMC4046937 DOI: 10.1371/journal.pntd.0002906] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 04/15/2014] [Indexed: 01/16/2023] Open
Abstract
Background Trypanosoma cruzi ribosomal P proteins, P2β and P0, induce high levels of antibodies in patients with chronic Chagas' disease Cardiomyopathy (CCC). It is well known that these antibodies alter the beating rate of cardiomyocytes and provoke apoptosis by their interaction with β1-adrenergic and M2-muscarinic cardiac receptors. Based on these findings, we decided to study the cellular immune response to these proteins in CCC patients compared to non-infected individuals. Methodology/Principal findings We evaluated proliferation, presence of surface activation markers and cytokine production in peripheral blood mononuclear cells (PBMC) stimulated with P2β, the C-terminal portion of P0 (CP0) proteins and T. cruzi lysate from CCC patients predominantly infected with TcVI lineage. PBMC from CCC patients cultured with P2β or CP0 proteins, failed to proliferate and express CD25 and HLA-DR on T cell populations. However, multiplex cytokine assays showed that these antigens triggered higher secretion of IL-10, TNF-α and GM-CSF by PBMC as well as both CD4+ and CD8+ T cells subsets of CCC subjects. Upon T. cruzi lysate stimulation, PBMC from CCC patients not only proliferated but also became activated within the context of Th1 response. Interestingly, T. cruzi lysate was also able to induce the secretion of GM-CSF by CD4+ or CD8+ T cells. Conclusions/Significance Our results showed that although the lack of PBMC proliferation in CCC patients in response to ribosomal P proteins, the detection of IL-10, TNF-α and GM-CSF suggests that specific T cells could have both immunoregulatory and pro-inflammatory potential, which might modulate the immune response in Chagas' disease. Furthermore, it was possible to demonstrate for the first time that GM-CSF was produced by PBMC of CCC patients in response not only to recombinant ribosomal P proteins but also to parasite lysate, suggesting the value of this cytokine to evaluate T cells responses in T. cruzi infection. Chronic Chagas' disease Cardiomyopathy (CCC) is the most frequent and severe consequence of the chronic infection by protozoan parasite T. cruzi. Patients with CCC develop high levels of antibodies against ribosomal P proteins of T. cruzi, called P2β and P0. These antibodies can cross-react with, and stimulate, the β1-adrenergic and M2 muscarinic cardiac receptors, inducing a functional and pathological response in cardiomyocytes. In this study, we focused on the cellular immune response developed by CCC patients in response to T. cruzi ribosomal P proteins. Peripheral blood mononuclear cells (PBMC) from CCC patients stimulated with both proteins neither proliferated nor induced the expression of activation markers on CD4+ and CD8+ T cells. However, these cells responded by the secretion of IL-10, TNF-α and GM-CSF, giving evidence that there is indeed a pool of specific T cells in the periphery responsive to these proteins. Interestingly, the cytokines profile was not related with those described to whole parasite lysate or other recombinant proteins, suggesting that each parasite protein may contribute differently to the complex immune response developed in patients with Chagas' disease.
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Affiliation(s)
- Silvia A. Longhi
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Buenos Aires, Argentina
- Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Augusto Atienza
- Hospital General de Agudos J.M. Ramos Mejía, Buenos Aires, Argentina
| | | | - Alcinette Buying
- Torrey Pines Institute for Molecular Studies, San Diego, California, United States of America
| | - Virginia Balouz
- Instituto de Investigaciones Biotecnológicas “Dr. Rodolfo Ugalde”, Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Campus UNSAM, San Martín, Buenos Aires, Argentina
| | - Carlos A. Buscaglia
- Instituto de Investigaciones Biotecnológicas “Dr. Rodolfo Ugalde”, Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Campus UNSAM, San Martín, Buenos Aires, Argentina
| | - Radleigh Santos
- Torrey Pines Institute for Molecular Studies, Port St. Lucie, Florida, United States of America
| | - Laura M. Tasso
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Buenos Aires, Argentina
| | - Ricardo Bonato
- Hospital General de Agudos J.M. Ramos Mejía, Buenos Aires, Argentina
| | - Pablo Chiale
- Hospital General de Agudos J.M. Ramos Mejía, Buenos Aires, Argentina
| | - Clemencia Pinilla
- Torrey Pines Institute for Molecular Studies, San Diego, California, United States of America
| | - Valeria A. Judkowski
- Torrey Pines Institute for Molecular Studies, San Diego, California, United States of America
| | - Karina A. Gómez
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Buenos Aires, Argentina
- Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
- * E-mail:
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19
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Xiong X, Qi Y, Jiao J, Gong W, Duan C, Wen B. Exploratory study on Th1 epitope-induced protective immunity against Coxiella burnetii infection. PLoS One 2014; 9:e87206. [PMID: 24498044 PMCID: PMC3907486 DOI: 10.1371/journal.pone.0087206] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 12/21/2013] [Indexed: 11/18/2022] Open
Abstract
Coxiella burnetii is a Gram-negative bacterium that causes Q fever in humans. In the present study, 131 candidate peptides were selected from the major immunodominant proteins (MIPs) of C. burnetii due to their high-affinity binding capacity for the MHC class II molecule H2 I-Ab based on bioinformatic analyses. Twenty-two of the candidate peptides with distinct MIP epitopes were well recognized by the IFN-γ recall responses of CD4+ T cells from mice immunized with parental proteins in an ELISPOT assay. In addition, 7 of the 22 peptides could efficiently induce CD4+ T cells from mice immunized with C. burnetii to rapidly proliferate and significantly increase IFN-γ production. Significantly higher levels of IL-2, IL-12p70, IFN-γ, and TNF-α were also detected in serum from mice immunized with a pool of the 7 peptides. Immunization with the pool of 7 peptides, but not the individual peptides, conferred a significant protection against C. burnetii infection in mice, suggesting that these Th1 peptides could work together to efficiently activate CD4+ T cells to produce the Th1-type immune response against C. burnetii infection. These observations could contribute to the rational design of molecular vaccines for Q fever.
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Affiliation(s)
- Xiaolu Xiong
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- * E-mail: (XX); (BW)
| | - Yong Qi
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Jun Jiao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Wenping Gong
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Changsong Duan
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Bohai Wen
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- * E-mail: (XX); (BW)
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20
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Gomez G, Adams LG, Rice-Ficht A, Ficht TA. Host-Brucella interactions and the Brucella genome as tools for subunit antigen discovery and immunization against brucellosis. Front Cell Infect Microbiol 2013; 3:17. [PMID: 23720712 PMCID: PMC3655278 DOI: 10.3389/fcimb.2013.00017] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 04/26/2013] [Indexed: 01/18/2023] Open
Abstract
Vaccination is the most important approach to counteract infectious diseases. Thus, the development of new and improved vaccines for existing, emerging, and re-emerging diseases is an area of great interest to the scientific community and general public. Traditional approaches to subunit antigen discovery and vaccine development lack consideration for the critical aspects of public safety and activation of relevant protective host immunity. The availability of genomic sequences for pathogenic Brucella spp. and their hosts have led to development of systems-wide analytical tools that have provided a better understanding of host and pathogen physiology while also beginning to unravel the intricacies at the host-pathogen interface. Advances in pathogen biology, host immunology, and host-agent interactions have the potential to serve as a platform for the design and implementation of better-targeted antigen discovery approaches. With emphasis on Brucella spp., we probe the biological aspects of host and pathogen that merit consideration in the targeted design of subunit antigen discovery and vaccine development.
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Affiliation(s)
- Gabriel Gomez
- Department of Veterinary Pathobiology, Texas A&M University College Station, TX 77843, USA.
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21
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Yin L, Calvo-Calle JM, Cruz J, Newman FK, Frey SE, Ennis FA, Stern LJ. CD4+ T cells provide intermolecular help to generate robust antibody responses in vaccinia virus-vaccinated humans. THE JOURNAL OF IMMUNOLOGY 2013; 190:6023-33. [PMID: 23667112 DOI: 10.4049/jimmunol.1202523] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Immunization with vaccinia virus elicits a protective Ab response that is almost completely CD4(+) T cell dependent. A recent study in a rodent model observed a deterministic linkage between Ab and CD4(+) T cell responses to particular vaccinia virus proteins suggesting that CD4(+) T cell help is preferentially provided to B cells with the same protein specificity (Sette et al. 2008. Immunity 28: 847-858). However, a causal linkage between Ab and CD4(+) T cell responses to vaccinia or any other large pathogen in humans has yet to be done. In this study, we measured the Ab and CD4(+) T cell responses against four vaccinia viral proteins (A27L, A33R, B5R, and L1R) known to be strongly targeted by humoral and cellular responses induced by vaccinia virus vaccination in 90 recently vaccinated and 7 long-term vaccinia-immunized human donors. Our data indicate that there is no direct linkage between Ab and CD4(+) T cell responses against each individual protein in both short-term and long-term immunized donors. Together with the observation that the presence of immune responses to these four proteins is linked together within donors, our data suggest that in vaccinia-immunized humans, individual viral proteins are not the primary recognition unit of CD4(+) T cell help for B cells. Therefore, we have for the first time, to our knowledge, shown evidence that CD4(+) T cells provide intermolecular (also known as noncognate or heterotypic) help to generate robust Ab responses against four vaccinia viral proteins in humans.
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Affiliation(s)
- Liusong Yin
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01655, USA
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Previously undescribed grass pollen antigens are the major inducers of T helper 2 cytokine-producing T cells in allergic individuals. Proc Natl Acad Sci U S A 2013; 110:3459-64. [PMID: 23401558 DOI: 10.1073/pnas.1300512110] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
T cells play an important role in the pathogenesis of allergic diseases. However, the proteins considered as potential immunogens of allergenic T-cell responses have traditionally been limited to those that induce IgE responses. Timothy grass (TG) pollen is a well-studied inhaled allergen for which major IgE-reactive allergens have also been shown to trigger T helper 2 (Th2) responses. Here we examined whether other TG pollen proteins are recognized by Th2 responses independently of IgE reactivity. A TG pollen extract was analyzed by 2D gel electrophoresis and IgE/IgG immunoblots using pooled sera from allergic donors. Mass spectrometry of selected protein spots in combination with de novo sequencing of the whole TG pollen transcriptome identified 93 previously undescribed proteins for further study, 64 of which were not targeted by IgE. Predicted MHC binding peptides from the previoulsy undescribed TG proteins were screened for T-cell reactivity in peripheral blood mononuclear cells from allergic donors. Strong IL-5 production was detected in response to peptides from several of the previously undescribed proteins, most of which were not targeted by IgE. Responses against the dominant undescribed epitopes were associated with the memory T-cell subset and could even be detected directly ex vivo after Th2 cell enrichment. These findings demonstrate that a combined unbiased transcriptomic, proteomic, and immunomic approach identifies a greatly broadened repertoire of protein antigens targeted by T cells involved in allergy pathogenesis. The discovery of proteins that induce Th2 cells but are not IgE reactive may allow the development of safer immunotherapeutic strategies.
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Hendrix LR, Chen C. Antigenic analysis for vaccines and diagnostics. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 984:299-328. [PMID: 22711639 DOI: 10.1007/978-94-007-4315-1_16] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Coxiella burnetii infection is frequently unrecognized or misdiagnosed, as symptoms generally mimic an influenza-like illness. However, the disease (Q fever) may result in chronic infection, usually manifesting as potentially fatal endocarditis. The development of a chronic fatigue-like sequela may also occur. Infected ruminants are the major reservoir for infection in humans, primarily through exposure to birth products or aerosols that transmit the bacterium over wide regions. A vaccine against C. burnetii infection has been in use in Australia for abattoir and agricultural workers for many years. The possibility of adverse reactions in those with previous exposure to the agent has prevented its use elsewhere. Subunit vaccines, utilizing chemical extraction of components thought to cause adverse reactions, are in development, but none are yet licensed. Others have sought to combine immunogenic peptides with or without selected lipopolysaccharide components to produce a vaccine without the possibility of adverse reactions. Selected immunogenic proteins have been shown to induce both humoral and cellular immune responses. Although current diagnosis of infection relies on serological testing, the presentation of specific antibody occurs 7-15 days following the onset of symptoms, delaying treatment that may result in prolonged morbidity. PCR detection of DNA to specific C. burnetii antigens in the blood is possible early in infection, but PCR may become negative when PII IgG antibodies appear. PCR is useful for early diagnosis when Q fever is suspected, as in large epidemics, and shortens the delay in the identification of Q fever endocarditis. Others have combined PCR with ELISA or other methods to increase the ability to detect infection at any stage. The search for new diagnostic reagents and vaccines has utilized new methods for discovery of immunoreactive proteins. DNA analysis of the heterogeneity of C. burnetii isolates has led to a greater understanding of the diversity of isolates and a means to determine whether there is a correlation between strain and disease severity. 2-D SDS PAGE of immunogenic proteins reactive with human or animal infection sera and mass spectrometric analysis of specific secreted or outer membrane proteins have identified candidate antigens. Microarrays have allowed the analysis of peptide libraries of open reading frames to evaluate the immunogenicity of complete genomes.
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Affiliation(s)
- Laura R Hendrix
- Department of Microbial and Molecular Pathogenesis, College of Medicine, Texas A&M Health Science Center, 3107 Medical Research and Education Building, Bryan, TX 77807-3260, USA.
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Maybeno M, Redeker A, Welten SPM, Peters B, Loughhead SM, Schoenberger SP, Sette A, Arens R. Polyfunctional CD4+ T cell responses to immunodominant epitopes correlate with disease activity of virulent Salmonella. PLoS One 2012; 7:e43481. [PMID: 22912884 PMCID: PMC3422266 DOI: 10.1371/journal.pone.0043481] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Accepted: 07/20/2012] [Indexed: 11/18/2022] Open
Abstract
Salmonella enterica serovars are intracellular bacteria capable of causing typhoid fever and gastroenteritis of significant morbidity and mortality worldwide. Current prophylactic and therapeutic treatment is hampered by the emergence of multidrug-resistant (MDR) strains of Salmonella, and vaccines provide only temporal and partial protection in vaccinees. To develop more effective Salmonella vaccines, it is important to understand the development of protective adaptive immunity to virulent Salmonella. Here we report the identification of novel CD4(+) T cell peptide epitopes, which are conserved among Salmonella serovars. Immunization of Salmonella-infected mice with these peptide epitopes reduces the burden of Salmonella disease. Furthermore, we show that distinct polyfunctional (interferon-γ(+), tumor necrosis factor(+), and interleukin-2(+)) Salmonella-specific CD4(+) T cell responses develop with respect to magnitude and kinetics. Moreover, we found that CD4(+) T cell responses against immunodominant epitopes are predictive for active Salmonella disease. Collectively, these data could contribute to improved diagnosis of Salmonella-related diseases and rational design of Salmonella vaccines.
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Affiliation(s)
- Matt Maybeno
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America
| | - Anke Redeker
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Suzanne P. M. Welten
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Bjoern Peters
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America
| | - Scott M. Loughhead
- Laboratory of Cellular Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America
| | - Stephen P. Schoenberger
- Laboratory of Cellular Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America
| | - Alessandro Sette
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America
| | - Ramon Arens
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
- * E-mail:
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Chaves FA, Lee AH, Nayak JL, Richards KA, Sant AJ. The utility and limitations of current Web-available algorithms to predict peptides recognized by CD4 T cells in response to pathogen infection. THE JOURNAL OF IMMUNOLOGY 2012; 188:4235-48. [PMID: 22467652 DOI: 10.4049/jimmunol.1103640] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The ability to track CD4 T cells elicited in response to pathogen infection or vaccination is critical because of the role these cells play in protective immunity. Coupled with advances in genome sequencing of pathogenic organisms, there is considerable appeal for implementation of computer-based algorithms to predict peptides that bind to the class II molecules, forming the complex recognized by CD4 T cells. Despite recent progress in this area, there is a paucity of data regarding the success of these algorithms in identifying actual pathogen-derived epitopes. In this study, we sought to rigorously evaluate the performance of multiple Web-available algorithms by comparing their predictions with our results--obtained by purely empirical methods for epitope discovery in influenza that used overlapping peptides and cytokine ELISPOTs--for three independent class II molecules. We analyzed the data in different ways, trying to anticipate how an investigator might use these computational tools for epitope discovery. We come to the conclusion that currently available algorithms can indeed facilitate epitope discovery, but all shared a high degree of false-positive and false-negative predictions. Therefore, efficiencies were low. We also found dramatic disparities among algorithms and between predicted IC(50) values and true dissociation rates of peptide-MHC class II complexes. We suggest that improved success of predictive algorithms will depend less on changes in computational methods or increased data sets and more on changes in parameters used to "train" the algorithms that factor in elements of T cell repertoire and peptide acquisition by class II molecules.
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Affiliation(s)
- Francisco A Chaves
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
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Porter SR, Czaplicki G, Mainil J, Guattéo R, Saegerman C. Q Fever: current state of knowledge and perspectives of research of a neglected zoonosis. Int J Microbiol 2011; 2011:248418. [PMID: 22194752 PMCID: PMC3238387 DOI: 10.1155/2011/248418] [Citation(s) in RCA: 133] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2011] [Accepted: 08/23/2011] [Indexed: 12/19/2022] Open
Abstract
Q fever is an ubiquitous zoonosis caused by an resistant intracellular bacterium, Coxiella burnetii. In certain areas, Q fever can be a severe public health problem, and awareness of the disease must be promoted worldwide. Nevertheless, knowledge of Coxiella burnetii remains limited to this day. Its resistant (intracellular and environmental) and infectious properties have been poorly investigated. Further understanding of the interactions between the infected host and the bacteria is necessary. Domestic ruminants are considered as the main reservoir of bacteria. Infected animals shed highly infectious organisms in milk, feces, urine, vaginal mucus, and, very importantly, birth products. Inhalation is the main route of infection. Frequently asymptomatic in humans and animals, Q fever can cause acute or chronic infections. Financial consequences of infection can be dramatic at herd level. Vaccination with inactive whole-cell bacteria has been performed and proved effective in humans and animals. However, inactive whole-cell vaccines present several defects. Recombinant vaccines have been developed in experimental conditions and have great potential for the future. Q fever is a challenging disease for scientists as significant further investigations are necessary. Great research opportunities are available to reach a better understanding and thus a better prevention and control of the infection.
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Affiliation(s)
- Sarah Rebecca Porter
- Research Unit in Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR), Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, University of Liège, B42, Boulevard de Colonster 20, 4000 Liège, Belgium
| | - Guy Czaplicki
- Département de Sérologie, Association Régionale de Santé et d'Identification Animales, 4431 Loncin, Belgium
| | - Jacques Mainil
- Laboratory of Bacteriology, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, University of Liège, Sart-Tilman B43a, 4000 Liège, Belgium
| | - Raphaël Guattéo
- UMR 1300 Bio-Agression, Epidémiologie et Analyse de Risque, INRA, 44307 Nantes, France
| | - Claude Saegerman
- Research Unit in Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR), Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, University of Liège, B42, Boulevard de Colonster 20, 4000 Liège, Belgium
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