1
|
Heterologous boosting with recombinant VSV-846 in BCG-primed mice confers improved protection against Mycobacterium infection. Hum Vaccin Immunother 2016; 13:816-822. [PMID: 27960596 DOI: 10.1080/21645515.2016.1261229] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Tuberculosis (TB) remains a major health problem worldwide, and the development of effective vaccines is urgently needed. Vaccination strategies based on heterologous prime-boost protocols using Mycobacterium bovis bacillus Calmette-Guérin (BCG) as primer and modified vaccinia virus Ankara strain expressing the mycobacterial antigen Ag85A (MVA85A) as booster may increase the protective efficacy of BCG. In addition, vaccination with the recombinant viral vaccine vesicular stomatitis virus (VSV)-846 (Rv3615c, Mtb10.4, and Rv2660c) can elicit a remarkable T-cell-mediated immune response and provide an effective long-term protection after the BCG challenge. In this study, we used VSV-846 to boost BCG and evaluated its immunogenicity in BALB/c mice. In this prime-boost approach, boosting with VSV-846 significantly enhanced IFN-γ CD4 T cell responses, which are crucial for anti-TB immune responses. Moreover, VSV-846 boosting significantly reduced pathology compared with mock vaccination, and decreased the bacterial loads in lung tissues compared with BCG or VSV-846 vaccination alone. The analysis of vaccine-induced immunity identified that polyfunctional T cells might contribute to the enhanced protection by VSV-846 boosting. This study proved that viral booster VSV-846 in mice improved the protection against mycobacteria infection, which could be helpful in designing an efficient vaccination strategy against TB in humans.
Collapse
|
2
|
Farrell D, Jones G, Pirson C, Malone K, Rue-Albrecht K, Chubb AJ, Vordermeier M, Gordon SV. Integrated computational prediction and experimental validation identifies promiscuous T cell epitopes in the proteome of Mycobacterium bovis. Microb Genom 2016; 2:e000071. [PMID: 28348866 PMCID: PMC5320590 DOI: 10.1099/mgen.0.000071] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 05/26/2016] [Indexed: 11/18/2022] Open
Abstract
The discovery of novel antigens is an essential requirement in devising new diagnostics or vaccines for use in control programmes against human tuberculosis (TB) and bovine tuberculosis (bTB). Identification of potential epitopes recognised by CD4+ T cells requires prediction of peptide binding to MHC class-II, an obligatory prerequisite for T cell recognition. To comprehensively prioritise potential MHC-II-binding epitopes from Mycobacterium bovis, the agent of bTB and zoonotic TB in humans, we integrated three binding prediction methods with the M. bovisproteome using a subset of human HLA alleles to approximate the binding of epitope-containing peptides to the bovine MHC class II molecule BoLA-DRB3. Two parallel strategies were then applied to filter the resulting set of binders: identification of the top-scoring binders or clusters of binders. Our approach was tested experimentally by assessing the capacity of predicted promiscuous peptides to drive interferon-γ secretion from T cells of M. bovis infected cattle. Thus, 376 20-mer peptides, were synthesised (270 predicted epitopes, 94 random peptides with low predictive scores and 12 positive controls of known epitopes). The results of this validation demonstrated significant enrichment (>24 %) of promiscuously recognised peptides predicted in our selection strategies, compared with randomly selected peptides with low prediction scores. Our strategy offers a general approach to the identification of promiscuous epitopes tailored to target populations where there is limited knowledge of MHC allelic diversity.
Collapse
Affiliation(s)
- Damien Farrell
- 1School of Veterinary Medicine, University College Dublin, Dublin D4, Ireland
| | - Gareth Jones
- 2Department of Bacteriology, Animal and Plant Health Agency, New Haw, Surrey KT15 3NB, UK
| | - Christopher Pirson
- 2Department of Bacteriology, Animal and Plant Health Agency, New Haw, Surrey KT15 3NB, UK
| | - Kerri Malone
- 1School of Veterinary Medicine, University College Dublin, Dublin D4, Ireland
| | - Kevin Rue-Albrecht
- 1School of Veterinary Medicine, University College Dublin, Dublin D4, Ireland.,3School of Agriculture and Food Science, University College Dublin, Dublin 4, Ireland
| | - Anthony J Chubb
- 4School of Medicine, University College Dublin, Dublin D4, Ireland
| | - Martin Vordermeier
- 2Department of Bacteriology, Animal and Plant Health Agency, New Haw, Surrey KT15 3NB, UK
| | - Stephen V Gordon
- 6School of Biomolecular and Biomedical Science, University College Dublin, Dublin 4, Ireland.,5Conway Institute of Biomolecular and Biomedical Science, University College Dublin, Dublin D4, Ireland.,1School of Veterinary Medicine, University College Dublin, Dublin D4, Ireland.,4School of Medicine, University College Dublin, Dublin D4, Ireland
| |
Collapse
|
3
|
Kaveh DA, Garcia-Pelayo MC, Webb PR, Wooff EE, Bachy VS, Hogarth PJ. Parenteral adenoviral boost enhances BCG induced protection, but not long term survival in a murine model of bovine TB. Vaccine 2016; 34:4003-11. [PMID: 27317453 DOI: 10.1016/j.vaccine.2016.06.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 05/25/2016] [Accepted: 06/09/2016] [Indexed: 10/21/2022]
Abstract
Boosting BCG using heterologous prime-boost represents a promising strategy for improved tuberculosis (TB) vaccines, and adenovirus (Ad) delivery is established as an efficacious boosting vehicle. Although studies demonstrate that intranasal administration of Ad boost to BCG offers optimal protection, this is not currently possible in cattle. Using Ad vaccine expressing the mycobacterial antigen TB10.4 (BCG/Ad-TB10.4), we demonstrate, parenteral boost of BCG immunised mice to induce specific CD8(+) IFN-γ producing T cells via synergistic priming of new epitopes. This induces significant improvement in pulmonary protection against Mycobacterium bovis over that provided by BCG when assessed in a standard 4week challenge model. However, in a stringent, year-long survival study, BCG/Ad-TB10.4 did not improve outcome over BCG, which we suggest may be due to the lack of additional memory cells (IL-2(+)) induced by boosting. These data indicate BCG-prime/parenteral-Ad-TB10.4-boost to be a promising candidate, but also highlight the need for further understanding of the mechanisms of T cell priming and associated memory using Ad delivery systems. That we were able to generate significant improvement in pulmonary protection above BCG with parenteral, rather than mucosal administration of boost vaccine is critical; suggesting that the generation of effective mucosal immunity is possible, without the risks and challenges of mucosal administration, but that further work to specifically enhance sustained protective immunity is required.
Collapse
Affiliation(s)
- Daryan A Kaveh
- Department of Bacteriology, Animal & Plant Health Agency (APHA), Woodham Lane, Addlestone, Surrey KT15 3NB, United Kingdom(1)
| | - M Carmen Garcia-Pelayo
- Department of Bacteriology, Animal & Plant Health Agency (APHA), Woodham Lane, Addlestone, Surrey KT15 3NB, United Kingdom(1)
| | - Paul R Webb
- Department of Bacteriology, Animal & Plant Health Agency (APHA), Woodham Lane, Addlestone, Surrey KT15 3NB, United Kingdom(1)
| | - Esen E Wooff
- Department of Bacteriology, Animal & Plant Health Agency (APHA), Woodham Lane, Addlestone, Surrey KT15 3NB, United Kingdom(1)
| | - Véronique S Bachy
- Department of Bacteriology, Animal & Plant Health Agency (APHA), Woodham Lane, Addlestone, Surrey KT15 3NB, United Kingdom(1)
| | - Philip J Hogarth
- Department of Bacteriology, Animal & Plant Health Agency (APHA), Woodham Lane, Addlestone, Surrey KT15 3NB, United Kingdom(1).
| |
Collapse
|
4
|
Boosting BCG with inert spores improves immunogenicity and induces specific IL-17 responses in a murine model of bovine tuberculosis. Tuberculosis (Edinb) 2016; 98:97-103. [PMID: 27156624 DOI: 10.1016/j.tube.2016.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 03/19/2016] [Indexed: 11/21/2022]
Abstract
Tuberculosis (TB) remains a global pandemic, in both animals and man, and novel vaccines are urgently required. Heterologous prime-boost of BCG represents a promising strategy for improved TB vaccines, with respiratory delivery the most efficacious to date. Such an approach may be an ideal vaccination strategy against bovine TB (bTB), but respiratory vaccination presents a technical challenge in cattle. Inert bacterial spores represent an attractive vaccine vehicle. Therefore we evaluated whether parenterally administered spores are efficacious when used as a BCG boost in a murine model of immunity against Mycobacterium bovis. Here we report the use of heat-killed, TB10.4 adsorbed, Bacillus subtilis spores delivered via subcutaneous injection to boost immunity primed by BCG. We demonstrate that this approach improves the immunogenicity of BCG. Interestingly, this associated with substantial boosting of IL-17 responses; considered to be important in protective immunity against TB. These data demonstrate that parenteral delivery of spores represents a promising vaccine vehicle for boosting BCG, and identifies potential for optimisation for use as a vaccine for bovine TB.
Collapse
|
5
|
A novel liposome adjuvant DPC mediates Mycobacterium tuberculosis subunit vaccine well to induce cell-mediated immunity and high protective efficacy in mice. Vaccine 2016; 34:1370-8. [PMID: 26845736 DOI: 10.1016/j.vaccine.2016.01.049] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 12/31/2015] [Accepted: 01/22/2016] [Indexed: 02/02/2023]
Abstract
Tuberculosis (TB) is a serious disease around the world, and protein based subunit vaccine is supposed to be a kind of promising novel vaccine against it. However, there is no effective adjuvant available in clinic to activate cell-mediated immune responses which is required for TB subunit vaccine. Therefore, it is imperative to develop new adjuvant. Here we reported an adjuvant composed of dimethyl dioctadecylammonium (DDA), Poly I:C and cholesterol (DPC for short). DDA can form a kind of cationic liposome with the ability to deliver and present antigen and can induce Th1 type cell-mediated immune response. Poly I:C, a ligand of TLR3 receptor, could attenuate the pathologic reaction induced by following Mycobacterium tuberculosis challenge. Cholesterol, which could enhance rigidity of lipid bilayer, is added to DDA and Poly I:C to improve the stability of the adjuvant. The particle size and Zeta-potential of DPC were analyzed in vitro. Furthermore, DPC was mixed with a TB fusion protein ESAT6-Ag85B-MPT64(190-198)-Mtb8.4-Rv2626c (LT70) to construct a subunit vaccine. The subunit vaccine-induced immune responses and protective efficacy against M. tuberculosis H37Rv infection in C57BL/6 mice were investigated. The results showed that the DPC adjuvant with particle size of 400 nm and zeta potential of 40 mV was in good stability. LT70 in the adjuvant of DPC generated strong antigen-specific humoral and cell-mediated immunity, and induced long-term higher protective efficacy against M. tuberculosis infection (5.41 ± 0.38log10CFU) than traditional vaccine Bacillus Calmette-Guerin (BCG) (6.01 ± 0.33log10CFU) and PBS control (6.53 ± 0.26log10CFU) at 30 weeks post-vaccination. In conclusion, DPC would be a promising vaccine adjuvant with the ability to stimulate Th1 type cell-mediated immunity, and could be used in TB subunit vaccine.
Collapse
|
6
|
Han PS, Orta P, Kwon DI, Inman JC. Mycobacterium bovis cervical lymphadenitis: A representative case and review. Int J Pediatr Otorhinolaryngol 2015; 79:1798-801. [PMID: 26388186 DOI: 10.1016/j.ijporl.2015.09.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 09/03/2015] [Accepted: 09/04/2015] [Indexed: 11/27/2022]
Abstract
Mycobacterium bovis is a tuberculosis causing bacterium that commonly presents with cervical lymphadenopathy. It is important to differentiate M. bovis from other Mycobacterial pathogens to ensure selection of correct anti-microbial therapy. This may decrease the number of treatment failures, the prevalence of anti-mycobacterial drug resistance patterns, and the need for surgical intervention. M. bovis has universal resistance to pyrazinamide and thus may not respond to typical first line mycobacterial drugs and may require surgical intervention. This case report and review of M. bovis cervical lymphadenitits demonstrates the need for accurate diagnosis as well as combined management with infectious disease and public health specialists.
Collapse
Affiliation(s)
- Peter S Han
- Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Pedro Orta
- Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Daniel I Kwon
- Department of Otolaryngology-Head and Neck Surgery, Loma Linda University Medical Center, Loma Linda, CA, USA.
| | - Jared C Inman
- Department of Otolaryngology-Head and Neck Surgery, Loma Linda University Medical Center, Loma Linda, CA, USA
| |
Collapse
|
7
|
Kaveh DA, Garcia-Pelayo MC, Hogarth PJ. Persistent BCG bacilli perpetuate CD4 T effector memory and optimal protection against tuberculosis. Vaccine 2014; 32:6911-6918. [PMID: 25444816 DOI: 10.1016/j.vaccine.2014.10.041] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 09/17/2014] [Accepted: 10/25/2014] [Indexed: 10/24/2022]
Abstract
Tuberculosis (TB) remains one of the most important infectious diseases of man and animals, and the only available vaccine (BCG) requires urgent replacement or improvement. To facilitate this, the protective mechanisms induced by BCG require further understanding. As a live attenuated vaccine, persistence of BCG bacilli in the host may be a crucial mechanism. We have investigated the long term persistence of BCG following vaccination and the influence on the induced immune response and protection, using an established murine model. We sought to establish whether previously identified BCG-specific CD4 TEM cells represent genuine long-lived memory cells of a relatively high frequency, or are a consequence of continual priming by chronically persistent BCG vaccine bacilli. By clearing persistent bacilli, we have compared immune responses (spleen and lung CD4: cytokine producing T effector/TEM; TCR-specific) and BCG-induced protection, in the presence and absence of these persisting vaccine bacilli. Viable BCG bacilli persisted for at least 16 months post-vaccination, associated with specific CD4 T effector/TEM and tetramer-specific responses. Clearing these bacilli abrogated all BCG-specific CD4 T cells whilst only reducing protection by 1log10. BCG may induce two additive mechanisms of immunity: (i) dependant on the presence of viable bacilli and TEM; and (ii) independent of these factors. These data have crucial implications on the rational generation of replacement TB vaccines, and the interpretation of BCG induced immunity in animal models.
Collapse
Affiliation(s)
- Daryan A Kaveh
- Vaccine Immunology Team, Department of Bacteriology, Animal and Plant Health Agency (APHA) Addlestone KT15 3NB, Surrey, UK
| | - M C Garcia-Pelayo
- Vaccine Immunology Team, Department of Bacteriology, Animal and Plant Health Agency (APHA) Addlestone KT15 3NB, Surrey, UK
| | - Philip J Hogarth
- Vaccine Immunology Team, Department of Bacteriology, Animal and Plant Health Agency (APHA) Addlestone KT15 3NB, Surrey, UK.
| |
Collapse
|
8
|
Brook RK, Wal EV, van Beest FM, McLachlan SM. Evaluating use of cattle winter feeding areas by elk and white-tailed deer: implications for managing bovine tuberculosis transmission risk from the ground up. Prev Vet Med 2012; 108:137-47. [PMID: 22940061 DOI: 10.1016/j.prevetmed.2012.07.017] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 07/18/2012] [Accepted: 07/29/2012] [Indexed: 10/27/2022]
Abstract
Transmission of bovine tuberculosis (Mycobacterium bovis) among wildlife and livestock has created important risks for conservation and agriculture. Management strategies aimed at controlling TB have typically been top-down, regionally focused, and government-led programs that were at best only partially successful. The purpose of this study was to quantify co-mingling of elk and white-tailed deer (WTD) with cattle at multiple spatial scales (i.e., the regional farm scale and winter cattle feeding area patch) in southwestern Manitoba, Canada, to assess the potential for bovine tuberculosis transmission and identify alternative management strategies. For each spatial scale we quantified use of cattle farms by elk and white-tailed deer. We mailed questionnaires to rural households and then conducted personal interviews with 86 cattle farmers to map the spatial distribution of their cattle winter feeding areas at a fine scale. We deployed Global Positioning System (GPS) collars on 48 wild elk and 16 wild white-tailed deer from 2003 to 2011. Elk were observed on farms by 66% of cattle producers, including 5% and 20% who observed direct and indirect contact, respectively, between elk and cattle. Cattle producers consistently (≈100%) observed white-tailed deer on their farms, including 11% and 47% whom observed direct and indirect contact, respectively, between white-tailed deer and cattle. A higher probability of white-tailed deer-cattle contact at the regional scale occurs on farms that (1) left crop residues specifically for wildlife, (2) had larger cattle herds, (3) used round bale feeders, and (4) were farther away from protected areas. None of the GPS-collared elk locations overlapped with cattle winter feeding areas. In contrast, 21% of GPS-collared white-tailed deer locations overlapped with winter cattle winter feeding areas (22% of these were from male WTD and 78% were from female WTD). White-tailed deer selected cattle winter feeding areas with higher (1) forage crop, (2) grassland/rangeland, and (3) forest cover around the cattle feeding area. Farmers overall expressed strongly negative attitudes toward eradicating the elk population or fencing the park to eradicate TB, but were generally supportive of less invasive and farm-based approaches. Our results suggested that management efforts to prevent TB transmission at the wildlife-agriculture interface can be effectively implemented using a 'bottom-up' approach that focuses on practical, farm-based mitigation strategies. This approach can be implemented by individual farm operators, is relatively low cost, and is generally well supported by farmers relative to other more extreme and controversial measures like wildlife eradication.
Collapse
Affiliation(s)
- Ryan K Brook
- Department of Animal and Poultry Science & Indigenous Land Management Institute, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
| | | | | | | |
Collapse
|
9
|
Migratory sub-populations of afferent lymphatic dendritic cells differ in their interactions with Mycobacterium bovis Bacille Calmette Guerin. Vaccine 2012; 30:2357-67. [DOI: 10.1016/j.vaccine.2012.01.036] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Revised: 12/05/2011] [Accepted: 01/12/2012] [Indexed: 01/12/2023]
|
10
|
Systemic BCG immunization induces persistent lung mucosal multifunctional CD4 T(EM) cells which expand following virulent mycobacterial challenge. PLoS One 2011; 6:e21566. [PMID: 21720558 PMCID: PMC3123368 DOI: 10.1371/journal.pone.0021566] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Accepted: 06/02/2011] [Indexed: 12/22/2022] Open
Abstract
To more closely understand the mechanisms of how BCG vaccination confers immunity would help to rationally design improved tuberculosis vaccines that are urgently required. Given the established central role of CD4 T cells in BCG induced immunity, we sought to characterise the generation of memory CD4 T cell responses to BCG vaccination and M. bovis infection in a murine challenge model. We demonstrate that a single systemic BCG vaccination induces distinct systemic and mucosal populations of T effector memory (TEM) cells in vaccinated mice. These CD4+CD44hiCD62LloCD27− T cells concomitantly produce IFN-γ and TNF-α, or IFN-γ, IL-2 and TNF-α and have a higher cytokine median fluorescence intensity MFI or ‘quality of response’ than single cytokine producing cells. These cells are maintained for long periods (>16 months) in BCG protected mice, maintaining a vaccine–specific functionality. Following virulent mycobacterial challenge, these cells underwent significant expansion in the lungs and are, therefore, strongly associated with protection against M. bovis challenge. Our data demonstrate that a persistent mucosal population of TEM cells can be induced by parenteral immunization, a feature only previously associated with mucosal immunization routes; and that these multifunctional TEM cells are strongly associated with protection. We propose that these cells mediate protective immunity, and that vaccines designed to increase the number of relevant antigen-specific TEM in the lung may represent a new generation of TB vaccines.
Collapse
|
11
|
Mycobacterium bovis antigens for the differential diagnosis of vaccinated and infected cattle. Vet Microbiol 2011; 151:8-13. [PMID: 21411245 DOI: 10.1016/j.vetmic.2011.02.020] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The urgency for new and improved cattle vaccines and diagnostic reagents for Bovine tuberculosis (TB) has made their development a research priority in Great Britain (GB). Significant progress has been made to develop specific antigens that allow the differentiation of BCG vaccinated and Mycobacterium bovis infected cattle (DIVA test). This has been greatly facilitated by the completion of the genome sequences of M. tuberculosis, M. bovis and BCG Pasteur and the subsequent application of comparative genome and transcriptome analysis to define DIVA antigens that complemented the prototype DIVA antigens ESAT-6 and CFP-10 by increasing their test sensitivity. Finally, we present an up-date of our current approaches in this area.
Collapse
|
12
|
Identification of surrogates and correlates of protection in protective immunity against Mycobacterium bovis infection induced in neonatal calves by vaccination with M. bovis BCG Pasteur and M. bovis BCG Danish. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2011; 18:373-9. [PMID: 21228141 DOI: 10.1128/cvi.00543-10] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Vaccination of neonatal calves with Mycobacterium bovis bacillus Calmette-Guérin (BCG) induces a significant degree of protection against infection with virulent M. bovis, the causative agent of bovine tuberculosis (bTB). We compared two strains of BCG, Pasteur and Danish, in order to confirm that the current European human vaccine strain (BCG Danish) induced protective immunity in calves, and we assessed immune responses to determine correlates of protection that could assist future vaccine evaluation in cattle. Both vaccine strains induced antigen (purified protein derivate [PPD])-specific gamma interferon (IFN-γ) in whole-blood cultures. These responses were not significantly different for BCG Pasteur and BCG Danish and peaked at week 2 to 4 postvaccination. Vaccination with either BCG Danish or BCG Pasteur induced significant protection against bTB, with reductions in both lesion score and bacteriological burden evident in both groups of vaccinated calves compared with nonvaccinated control calves. Measurement of IFN-γ-expressing T lymphocytes postvaccination and postchallenge revealed both correlates and surrogates of protective efficacy. The frequency of central memory T lymphocytes present at 12 weeks postvaccination (at the time of M. bovis challenge) correlated significantly with protection. Conversely, the number of IFN-γ-expressing effector T cells present after M. bovis challenge was correlated with disease. These results demonstrate that vaccination of neonatal calves with either BCG Pasteur or BCG Danish induces protective immune responses against TB. In addition, we show that measurement of antigen-specific T lymphocyte populations may provide a reliable means for identifying protective vaccine candidates.
Collapse
|
13
|
Development of a skin test for bovine tuberculosis for differentiating infected from vaccinated animals. J Clin Microbiol 2010; 48:3176-81. [PMID: 20592155 DOI: 10.1128/jcm.00420-10] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The tuberculin skin test has been used for the diagnosis of bovine and human tuberculosis (TB) for over a hundred years. However, the specificity of the test is compromised by vaccination with the Mycobacterium bovis-derived vaccine strain bacille Calmette-Guérin (BCG). Since current promising vaccines against bovine TB are based on heterologous prime-boost combinations that include BCG, there is a need for diagnostic tests for differentiating infected from vaccinated animals (DIVA). The application of antigens such as ESAT-6 and CFP-10 for DIVA has so far been realized largely through their application in the blood-based gamma interferon release assay. In the current study, we have reassessed the potential of such antigens as skin test reagents for DIVA in cattle. A cocktail of the Mycobacterium tuberculosis complex recombinant protein antigens ESAT-6, CFP-10, MPB70, and MPB83 elicited delayed-type hypersensitivity (DTH) skin test responses in 78% of naturally infected tuberculin-positive cattle. Importantly, this cocktail induced no skin responses in BCG-vaccinated cattle despite them being sensitized for strong tuberculin responses. Further optimization of skin test antigen combinations identified that the inclusion of Rv3615c (Mb3645c) enhanced skin test sensitivity in naturally infected cattle without compromising specificity. In addition, we demonstrate for the first time the utility of synthetic peptides as promising skin test antigens for bovine TB for DIVA. Our data provide a promising basis for the future development of skin tests for DIVA with practical relevance for TB diagnosis in both veterinary and clinical settings.
Collapse
|
14
|
Adjuvants induce distinct immunological phenotypes in a bovine tuberculosis vaccine model. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2009; 16:1443-8. [PMID: 19641101 DOI: 10.1128/cvi.00229-09] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Tuberculosis (TB) remains one of the most important infectious diseases of humans and animals. Mycobacterium bovis BCG, the only currently available TB vaccine, demonstrates variable levels of efficacy; therefore, a replacement or supplement to BCG is required. Protein subunit vaccines have shown promise but require the use of adjuvants to enhance their immunogenicity. Using the protective mycobacterial antigen Rv3019c, we have evaluated the induction of relevant immune responses by adjuvant formulations directly in the target species for bovine TB vaccines and compared these to responses induced by BCG. We demonstrate that two classes of adjuvant induce distinct immune phenotypes in cattle, a fact not previously reported for mice. A water/oil emulsion induced both an effector cell and a central memory response. A cationic-liposome adjuvant induced a central memory response alone, similar to that induced by BCG. This suggests that water/oil emulsions may be the most promising formulations. These results demonstrate the importance of testing adjuvant formulations directly in the target species and the necessity of measuring different types of immune response when evaluating immune responses.
Collapse
|
15
|
Vordermeier M, Gordon SV, Hewinson ARG. Antigen mining to define Mycobacterium bovis antigens for the differential diagnosis of vaccinated and infected animals: A VLA perspective. Transbound Emerg Dis 2009; 56:240-7. [PMID: 19413883 DOI: 10.1111/j.1865-1682.2009.01070.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The urgency for new and improved cattle vaccines and diagnostic reagents has been acknowledged by the UK Government, and development of cattle vaccine is a research priority. Significant progress has been made to develop specific antigens that allow the differentiation of bacille Calmette-Guerin (BCG) vaccinated and M. bovis-infected cattle [diagnosis of infected from vaccinated individuals (DIVA) test]. This progress has been greatly facilitated by the completion of the genome sequences of Mycobacterium tuberculosis, M. bovis and BCG Pasteur. In this study, we describe how we applied this knowledge, through comparative genome and transcriptome analysis, to define DIVA antigens that complemented the prototype DIVA antigens ESAT-6 and CFP-10 by increasing their test sensitivity. In addition, we draw general conclusions from our experience, and discuss potential future approaches in this area.
Collapse
Affiliation(s)
- M Vordermeier
- Veterinary Laboratories Agency - Weybridge, TB Research Group, New Haw, Surrey, UK.
| | | | | |
Collapse
|
16
|
Endsley JJ, Waters WR, Palmer MV, Nonnecke BJ, Thacker TC, Jacobs WR, Larsen MH, Hogg A, Shell E, McAlauy M, Scherer CFC, Coffey T, Howard CJ, Villareal-Ramos B, Estes DM. The calf model of immunity for development of a vaccine against tuberculosis. Vet Immunol Immunopathol 2009; 128:199-204. [DOI: 10.1016/j.vetimm.2008.10.312] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
17
|
Logan KE, Gavier-Widen D, Hewinson RG, Hogarth PJ. Development of a Mycobacterium bovis intranasal challenge model in mice. Tuberculosis (Edinb) 2008; 88:437-43. [DOI: 10.1016/j.tube.2008.05.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2008] [Revised: 04/03/2008] [Accepted: 05/04/2008] [Indexed: 11/28/2022]
|