Cell-Mediated Immunological Biomarkers and Their Diagnostic Application in Livestock and Wildlife Infected With Mycobacterium bovis

Mycobacterium bovis has the largest host range of the Mycobacterium tuberculosis complex and infects domestic animal species, wildlife, and humans. The presence of global wildlife maintenance hosts complicates bovine tuberculosis (bTB) control efforts and further threatens livestock and wildlife-related industries. Thus, it is imperative that early and accurate detection of M. bovis in all affected animal species is achieved. Further, an improved understanding of the complex species-specific host immune responses to M. bovis could enable the development of diagnostic tests that not only identify infected animals but distinguish between infection and active disease. The primary bTB screening standard worldwide remains the tuberculin skin test (TST) that presents several test performance and logistical limitations. Hence additional tests are used, most commonly an interferon-gamma (IFN-γ) release assay (IGRA) that, similar to the TST, measures a cell-mediated immune (CMI) response to M. bovis. There are various cytokines and chemokines, in addition to IFN-γ, involved in the CMI component of host adaptive immunity. Due to the dominance of CMI-based responses to mycobacterial infection, cytokine and chemokine biomarkers have become a focus for diagnostic tests in livestock and wildlife. Therefore, this review describes the current understanding of host immune responses to M. bovis as it pertains to the development of diagnostic tools using CMI-based biomarkers in both gene expression and protein release assays, and their limitations. Although the study of CMI biomarkers has advanced fundamental understanding of the complex host-M. bovis interplay and bTB progression, resulting in development of several promising diagnostic assays, most of this research remains limited to cattle. Considering differences in host susceptibility, transmission and immune responses, and the wide variety of M. bovis-affected animal species, knowledge gaps continue to pose some of the biggest challenges to the improvement of M. bovis and bTB diagnosis.

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Using Data from Macaques To Predict Gamma Interferon Responses after Mycobacterium bovis BCG Vaccination in Humans: a Proof-of-Concept Study of Immunostimulation/Immunodynamic Modeling Methods

Clinical and Vaccine Immunology ◽

10.1128/cvi.00525-16 ◽

2017 ◽

Vol 24 (3) ◽

Cited By ~ 5

Author(s):

Sophie J. Rhodes ◽

Charlotte Sarfas ◽

Gwenan M. Knight ◽

Andrew White ◽

Ansar A. Pathan ◽

...

Keyword(s):

Immune Response ◽

Immune Responses ◽

Mycobacterium Bovis ◽

Gamma Interferon ◽

Proof Of Concept ◽

Concept Study ◽

Bcg Vaccination ◽

Modeling Methods ◽

Cynomolgus Macaques ◽

Ifn Γ

ABSTRACT Macaques play a central role in the development of human tuberculosis (TB) vaccines. Immune and challenge responses differ across macaque and human subpopulations. We used novel immunostimulation/immunodynamic modeling methods in a proof-of-concept study to determine which macaque subpopulations best predicted immune responses in different human subpopulations. Data on gamma interferon (IFN-γ)-secreting CD4+ T cells over time after recent Mycobacterium bovis BCG vaccination were available for 55 humans and 81 macaques. Human population covariates were baseline BCG vaccination status, time since BCG vaccination, gender, and the monocyte/lymphocyte cell count ratio. The macaque population covariate was the colony of origin. A two-compartment mathematical model describing the dynamics of the IFN-γ T cell response after BCG vaccination was calibrated to these data using nonlinear mixed-effects methods. The model was calibrated to macaque and human data separately. The association between subpopulations and the BCG immune response in each species was assessed. The macaque subpopulations that best predicted immune responses in different human subpopulations were identified using Bayesian information criteria. We found that the macaque colony and the human baseline BCG status were significantly (P < 0.05) associated with the BCG-induced immune response. For humans who were BCG naïve at baseline, Indonesian cynomolgus macaques and Indian rhesus macaques best predicted the immune response. For humans who had already been BCG vaccinated at baseline, Mauritian cynomolgus macaques best predicted the immune response. This work suggests that the immune responses of different human populations may be best modeled by different macaque colonies, and it demonstrates the potential utility of immunostimulation/immunodynamic modeling to accelerate TB vaccine development.

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Host Susceptibility toBrucella abortusInfection Is More Pronounced in IFN-γknockout than IL-12/β2-Microglobulin Double-Deficient Mice

Clinical and Developmental Immunology ◽

10.1155/2012/589494 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 32

Author(s):

Ana Paula M. S. Brandão ◽

Fernanda S. Oliveira ◽

Natalia B. Carvalho ◽

Leda Q. Vieira ◽

Vasco Azevedo ◽

...

Keyword(s):

T Cells ◽

Immune Responses ◽

Cd8 T Cells ◽

Bacterial Load ◽

Bacterial Pathogen ◽

Domestic Animals ◽

Host Susceptibility ◽

Mouse Splenocytes ◽

Host Immune Responses ◽

Deficient Mice

Brucella abortusis a facultative intracellular bacterial pathogen that causes abortion in domestic animals and undulant fever in humans. IFN-γ, IL-12, and CD8+ T lymphocytes are important components of host immune responses againstB. abortus. Herein, IFN-γand IL-12/β2-microglobulin (β2-m) knockout mice were used to determine whether CD8+ T cells and IL-12-dependent IFN-γdeficiency would be more critical to controlB. abortusinfection compared to the lack of endogenous IFN-γ. At 1 week after infection, IFN-γKO and IL-12/β2-m KO mice showed increased numbers of bacterial load in spleens; however, at 3 weeks postinfection (p.i.), only IFN-γKO succumbed toBrucella. All IFN-γKO had died at 16 days p.i. whereas death within the IL-12/β2-m KO group was delayed and occurred at 32 days until 47 days postinfection. Susceptibility of IL-12/β2-m KO animals toBrucellawas associated to undetectable levels of IFN-γin mouse splenocytes and inability of these cells to lyseBrucella-infected macrophages. However, the lack of endogenous IFN-γwas found to be more important to control brucellosis than CD8+ T cells and IL-12-dependent IFN-γdeficiencies.

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ERAP1 and PDE8A Are Downregulated in Cattle Protected against Bovine Tuberculosis

Journal of Molecular Microbiology and Biotechnology ◽

10.1159/000479183 ◽

2017 ◽

Vol 27 (4) ◽

pp. 237-245 ◽

Cited By ~ 2

Author(s):

Federico Carlos Blanco ◽

Marcelo Abel Soria ◽

Laura Inés Klepp ◽

Fabiana Bigi

Keyword(s):

Immune Responses ◽

Mycobacterium Bovis ◽

Bovine Tuberculosis ◽

Economic Losses ◽

Effective Vaccine ◽

Immune Protection ◽

Host Proteins ◽

Defence Mechanisms ◽

Effective Protection ◽

Host Immune Responses

Bovine tuberculosis (bTB) is a zoonotic disease caused by Mycobacterium bovis that is responsible for significant economic losses worldwide. In spite of its relevance, the limited knowledge about the host immune responses that provide effective protection against the disease has long hampered the development of an effective vaccine. The identification of host proteins with an expression that correlates with protection against bTB would contribute to the understanding of the cattle defence mechanisms against M. bovis infection. In this study, we found that ERAP1 and PDE8A were downregulated in vaccinated cattle that were protected from experimental M. bovis challenge. Remarkably, both genes encode proteins that have been negatively associated with immune protection against bTB.

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Cellular Immune Responses to Recombinant Mycobacterium bovis BCG Constructs Expressing Major Antigens of Region of Difference 1 of Mycobacterium tuberculosis

Clinical and Vaccine Immunology ◽

10.1128/cvi.00090-12 ◽

2013 ◽

Vol 20 (8) ◽

pp. 1230-1237 ◽

Cited By ~ 7

Author(s):

Kholoud Shaban ◽

Hanady A. Amoudy ◽

Abu S. Mustafa

Keyword(s):

Immune Responses ◽

Mycobacterium Bovis ◽

Protective Efficacy ◽

Spleen Cells ◽

T Helper 1 ◽

Th1 Cell ◽

Content Type ◽

Cellular Immune Responses ◽

Ifn Γ ◽

Cellular Immune

ABSTRACTBesides being the most widely used vaccine directed against tuberculosis (TB) worldwide,Mycobacterium bovisBCG is also the most controversial vaccine in current use. Its protective efficacy varies widely in different parts of the world. One approach to improving the current BCG vaccine might be to produce recombinant BCG strains that express major antigens encoded by genes that are present in theM. tuberculosis-specific region of difference 1 (RD1), such aspe35,cfp10, andesat6. In this study,pe35,cfp10, andesat6genes were cloned into shuttle plasmid pDE22 to generate the recombinant plasmids PDE22-PE35, PDE22-CFP10, and PDE22-ESAT6, which were electroporated into BCG to generate recombinant BCGs (rBCGs). The cellular immune responses (antigen-induced proliferation and secretion of selected T helper 1 [Th1], Th2, and anti-inflammatory cytokines, i.e., gamma interferon [IFN-γ], interleukin 5 [IL-5], and IL-10, respectively) that are specific to the proteins of cloned genes were studied by using spleen cells from mice immunized with native BCGs and rBCGs and synthetic peptides covering the protein sequence of the cloned genes. The results showed that the spleen cells did not secrete IL-5, whereas IL-10 was secreted in response to peptides of all three proteins from mice immunized with rBCGs only, suggesting expression of the cloned genes andin vivopriming of spleen cells to the expressed proteins. However, in Th1 cell assays that correlate with protective cellular immune responses, i.e., antigen-induced proliferation and IFN-γ secretion, only mice immunized with rBCG-pDE22-PE35 yielded positive responses to the peptides of PE35. These results suggest that rBCG-PDE22-PE35 is the only one of the three vaccines used in this work that is worthy of consideration as a new vaccine candidate against TB.

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Pathways for Potentiation of Immunogenicity during Adjuvant-Assisted Immunizations with Plasmodium falciparumMajor Merozoite Surface Protein 1

Infection and Immunity ◽

10.1128/iai.66.11.5329-5336.1998 ◽

1998 ◽

Vol 66 (11) ◽

pp. 5329-5336 ◽

Cited By ~ 12

Author(s):

George S. N. Hui ◽

Caryn N. Hashimoto

Keyword(s):

Immune Responses ◽

Animal Species ◽

Surface Protein ◽

Merozoite Surface Protein ◽

Mouse Strains ◽

Vaccine Adjuvants ◽

Merozoite Surface Protein 1 ◽

Ifn Γ ◽

Animal Hosts

Vaccine adjuvants exert critical and unique influences on the quality of immune responses induced during active immunizations. We investigated the mechanisms of action of immunological adjuvants in terms of their requirements for cytokine-mediated pathways for adjuvanticity. Antibody responses potentiated by several adjuvants to a Plasmodium falciparum MSP1-19 (C-terminal 19-kDa processing fragment of MSP1) vaccine were studied in gamma interferon (IFN-γ) or interleukin (IL-4) knockout mice. The levels of anti-MSP1-19 antibodies and the induction of Th1- and Th2-type antibodies were analyzed. Results revealed a spectrum of requirements for cytokine-mediated pathways in the potentiation of immunogenicity, and such requirements were influenced by interactions among individual components of the adjuvant formulations. One adjuvant strictly depended on IFN-γ to induce appreciable levels of anti-MSP1-19 antibodies, while some formulations required IFN-γ only for the induction of Th1-type antibodies. Other formulations induced exclusively Th2-type antibodies and were not affected by IFN-γ knockout. There were three patterns of requirements for IL-4 by various adjuvants in the induction of Th2-type anti-MSP1-19 antibodies. Moreover, the induction of Th1-type anti-MSP1-19 antibodies by adjuvants showed two distinct patterns of regulation by IL-4. The utilization of an IL-4 regulated pathway(s) for the induction of Th2-type antibodies by the same adjuvant differed between mouse strains, suggesting that animal species variability in responses to vaccine adjuvants may be due, at least in part, to differences in the utilization of immune system pathways by an adjuvant among animal hosts.

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Nonencapsulated Trichinella pseudospiralis Infection Impairs Follicular Helper T Cell Differentiation with Subclass-Selective Decreases in Antibody Responses

Infection and Immunity ◽

10.1128/iai.00597-16 ◽

2016 ◽

Vol 84 (12) ◽

pp. 3550-3556 ◽

Cited By ~ 2

Author(s):

Kazunobu Asano ◽

Zhiliang Wu ◽

Piyarat Srinontong ◽

Takahide Ikeda ◽

Isao Nagano ◽

...

Keyword(s):

Cell Differentiation ◽

Immune Responses ◽

Humoral Immunity ◽

Trichinella Spiralis ◽

Muscle Cells ◽

Affinity Maturation ◽

Content Type ◽

Host Immune Responses ◽

Follicular Helper ◽

Ifn Γ

Infectious microorganisms often modify host immunity to escape from immune elimination. Trichinella is a unique nematode of the helminth family, whose members parasitize the muscle cells inside the host without robust eliminative reactions. There are several species of Trichinella ; some develop in muscle cells that become encapsulated (e.g., Trichinella spiralis ) and others in cells that do not encapsulate (e.g., Trichinella pseudospiralis ). It has already been established that Trichinella infection affects host immune responses in several experimental immune diseases in animal models; however, most of those studies were done using T. spiralis infection. As host immune responses to T. spiralis and T. pseudospiralis infections have been reported to be different, it is necessary to clarify how T. pseudospiralis infection influences the host immune responses. In this study, we investigated the influence on host humoral immunity in T. pseudospiralis -infected mice. We demonstrated that T. pseudospiralis infection decreased antigen-specific IgG2a and IgG2b antibody (Ab) production in mice immunized with a model antigen. This selective decrease in gamma interferon (IFN-γ)-dependent Ab production was not due to a decrease in IFN-γ production, and we instead found impaired follicular helper T (Tfh) cell differentiation. The affinity maturation of antigen-specific Ab tended to be delayed but was not significant in T. pseudospiralis -infected mice. We also observed that CD11b + spleen cells in T. pseudospiralis -infected mice expressed CD206 and PD-L2, the phenotype of which was M2 macrophages with weak production of interleukin-6 (IL-6), possibly resulting in impaired Tfh differentiation. Taken together, our results indicate that nonencapsulated Trichinella infection induces selective dampening in humoral immunity with the suppression of Tfh differentiation.

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Modulation of Immune Responses to Mycobacterium bovis in Cattle Depleted of WC1+ γδ T Cells

Infection and Immunity ◽

10.1128/iai.70.3.1488-1500.2002 ◽

2002 ◽

Vol 70 (3) ◽

pp. 1488-1500 ◽

Cited By ~ 65

Author(s):

Hilary E. Kennedy ◽

Michael D. Welsh ◽

David G. Bryson ◽

Joseph P. Cassidy ◽

Fiona I. Forster ◽

...

Keyword(s):

Immune Response ◽

T Cells ◽

Immune Responses ◽

Mycobacterium Bovis ◽

Bovine Tuberculosis ◽

Γδ T Cells ◽

Interleukin 4 ◽

In Vivo Model ◽

Peripheral Blood Mononuclear ◽

Ifn Γ

ABSTRACT It is accepted that cell-mediated immune responses predominate in mycobacterial infections. Many studies have shown that CD4+ T cells produce Th1 cytokines, such as gamma interferon (IFN-γ), in response to mycobacterial antigens and that the cytolytic activity of CD8+ cells toward infected macrophages is important. However, the extent and manner in which γδ T cells participate in this response remain unclear. In ruminants, γδ T cells comprise a major proportion of the peripheral blood mononuclear cell population. We have previously shown that WC1+ γδ T cells are involved early in Mycobacterium bovis infection of cattle, but their specific functions are not well understood. Here we describe an in vivo model of bovine tuberculosis in which the WC1+ γδ T cells were depleted from the peripheral circulation and respiratory tract, by infusion of WC1+-specific monoclonal antibody, prior to infection. While no effects on disease pathology were observed in this experiment, results indicate that WC1+ γδ T cells, which become significantly activated (CD25+) in the circulation of control calves from 21 days postinfection, may play a role in modulating the developing immune response to M. bovis. WC1+-depleted animals exhibited decreased antigen-specific lymphocyte proliferative response, an increased antigen-specific production of interleukin-4, and a lack of specific immunoglobulin G2 antibody. This suggests that WC1+ γδ TCR+ cells contribute, either directly or indirectly, toward the Th1 bias of the immune response in bovine tuberculosis—a hypothesis supported by the decreased innate production of IFN-γ, which was observed in WC1+-depleted calves.

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Genetic Screen inChlamydia muridarumReveals Role for an Interferon-Induced Host Cell Death Program in Antimicrobial Inclusion Rupture

mBio ◽

10.1128/mbio.00385-19 ◽

2019 ◽

Vol 10 (2) ◽

Cited By ~ 4

Author(s):

Amanda M. Giebel ◽

Shuai Hu ◽

Krithika Rajaram ◽

Ryan Finethy ◽

Evelyn Toh ◽

...

Keyword(s):

Cell Death ◽

Immune Responses ◽

Host Cell ◽

Host Defense ◽

Genetic Screen ◽

Content Type ◽

Host Immune Responses ◽

Interferon Stimulated Genes ◽

Host Cell Death ◽

Ifn Γ

ABSTRACTInterferon-regulated immune defenses protect mammals from pathogenically diverse obligate intracellular bacterial pathogens of the genusChlamydia. Interferon gamma (IFN-γ) is especially important in controlling the virulence ofChlamydiaspecies and thus impacts the modeling of human chlamydial infection and disease in mice. How IFN-γ contributes to cell-autonomous defenses againstChlamydiaspecies and how these pathogens evade IFN-γ-mediated immunity in their natural hosts are not well understood. We conducted a genetic screen which identified 31IFN-γ-sensitive (Igs) mutants of the mouse model pathogenChlamydia muridarum. Genetic suppressor analysis and lateral gene transfer were used to map the phenotype of one of these mutants, Igs4, to a missense mutation in a putative chlamydial inclusion membrane protein, TC0574. We observed the lytic destruction of Igs4-occupied inclusions and accompanying host cell death in response to IFN-γ priming or various proapoptotic stimuli. However, Igs4 was insensitive to IFN-γ-regulated cell-autonomous defenses previously implicated in anti-Chlamydia trachomatishost defense in mice. Igs4 inclusion integrity was restored by caspase inhibitors, indicating that the IFN-γ-mediated destruction of Igs4 inclusions is dependent upon the function of caspases or related prodeath cysteine proteases. We further demonstrated that the Igs4 mutant is immune restricted in an IFN-γ-dependent manner in a mouse infection model, thereby implicating IFN-γ-mediated inclusion destruction and host cell death as potentin vivohost defense mechanisms to which wild-typeC. muridarumis resistant. Overall, our results suggest thatC. muridarumevolved resistance mechanisms to counter IFN-γ-elicited programmed cell death and the associated destruction of intravacuolar pathogens.IMPORTANCEMultiple obligatory intracellular bacteria in the genusChlamydiaare important pathogens. In humans, strains ofC. trachomatiscause trachoma, chlamydia, and lymphogranuloma venereum. These diseases are all associated with extended courses of infection and reinfection that likely reflect the ability of chlamydiae to evade various aspects of host immune responses. Interferon-stimulated genes, driven in part by the cytokine interferon gamma, restrict the host range of variousChlamydiaspecies, but how these pathogens evade interferon-stimulated genes in their definitive host is poorly understood. VariousChlamydiaspecies can inhibit death of their host cells and may have evolved this strategy to evade prodeath signals elicited by host immune responses. We present evidence that chlamydia-induced programmed cell death resistance evolved to counter interferon- and immune-mediated killing ofChlamydia-infected cells.

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Genetically Determined Disparate Innate and Adaptive Cell-Mediated Immune Responses to Pulmonary Mycobacterium bovis BCG Infection in C57BL/6 and BALB/c Mice

Infection and Immunity ◽

10.1128/iai.68.12.6946-6953.2000 ◽

2000 ◽

Vol 68 (12) ◽

pp. 6946-6953 ◽

Cited By ~ 61

Author(s):

Julia Wakeham ◽

Jun Wang ◽

Zhou Xing

Keyword(s):

Immune Response ◽

Immune Responses ◽

Mycobacterium Bovis ◽

Genetic Heterogeneity ◽

Mycobacterial Infection ◽

Interleukin 12 ◽

Lymphoid Tissues ◽

Ifn Γ ◽

The Impact

ABSTRACT The current study was designed to investigate the impact of genetic heterogeneity on host immune responses to pulmonary intracellular infection by using two mouse strains of distinct genetic background, C57BL/6 and BALB/c mice, and a model intracellular pathogen,Mycobacterium bovis BCG. Upon infection, compared to C57BL/6 mice, BALB/c mice developed an earlier response of interleukin 12 (IL-12), gamma interferon (IFN-γ), tumor necrosis factor alpha, and macrophage chemoattractive protein 1, and greater neutrophilic influx to the lung by days 7 and 14. However, the level of these cytokines at days 27, 43, and 71 was much lower in BALB/c mice than in C57BL/6 mice. The magnitude of cellular responses was also much lower in the lung of BALB/c mice around day 27. Histologically, while C57BL/6 mice developed lymphocytic granulomas, BALB/c mice displayed atypical granulomas in the lung. Of importance, the level of type 2 cytokines IL-4 and IL-10 remained low and similar in the lung of both C57BL/6 and BALB/c mice throughout. Furthermore, lymphocytes isolated from systemic and local lymphoid tissues of infected BALB/c mice demonstrated a markedly lower antigen-specific IFN-γ recall response. While the number of mycobacterial bacilli recovered from both the lung and spleen of BALB/c mice was similar to that in C57BL/6 mice at day 14, it was higher than that in C57BL/6 mice at day 43. However, it was eventually leveled off to that in C57BL/6 counterparts later. These results suggest the following: (i) genetic heterogeneity can lead to differential innate and adaptive cell-mediated immune responses to primary pulmonary mycobacterial infection; (ii) it is the level of adaptive, but not innate, immune response that is critical to host resistance; and (iii) a lower type 1 immune response in BALB/c mice is not accompanied by a heightened type 2 response during pulmonary mycobacterial infection.

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