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1.
Cell ; 167(2): 433-443.e14, 2016 Oct 06.
Article in English | MEDLINE | ID: mdl-27667685

ABSTRACT

While a third of the world carries the burden of tuberculosis, disease control has been hindered by a lack of tools, including a rapid, point-of-care diagnostic and a protective vaccine. In many infectious diseases, antibodies (Abs) are powerful biomarkers and important immune mediators. However, in Mycobacterium tuberculosis (Mtb) infection, a discriminatory or protective role for humoral immunity remains unclear. Using an unbiased antibody profiling approach, we show that individuals with latent tuberculosis infection (Ltb) and active tuberculosis disease (Atb) have distinct Mtb-specific humoral responses, such that Ltb infection is associated with unique Ab Fc functional profiles, selective binding to FcγRIII, and distinct Ab glycosylation patterns. Moreover, compared to Abs from Atb, Abs from Ltb drove enhanced phagolysosomal maturation, inflammasome activation, and, most importantly, macrophage killing of intracellular Mtb. Combined, these data point to a potential role for Fc-mediated Ab effector functions, tuned via differential glycosylation, in Mtb control.


Subject(s)
Antibodies, Bacterial/immunology , Host-Pathogen Interactions/immunology , Immunity, Humoral , Latent Tuberculosis/immunology , Mycobacterium tuberculosis/immunology , Adult , Female , Glycosylation , Humans , Immunoglobulin Fc Fragments/immunology , Macrophage Activation , Male , Middle Aged , Polysaccharides/immunology , Protein Array Analysis , Receptors, IgG/immunology , Young Adult
2.
Am J Respir Crit Care Med ; 201(4): 469-477, 2020 02 15.
Article in English | MEDLINE | ID: mdl-31647877

ABSTRACT

Rationale: Direct evidence for persistence of Mycobacterium tuberculosis (Mtb) during asymptomatic latent tuberculosis infection (LTBI) in humans is currently lacking. Moreover, although a 12-week regimen of once-weekly isoniazid and rifapentine (3HP) is currently recommended by the CDC as treatment for LTBI, experimental evidence for 3HP-mediated clearance of persistent Mtb infection in human lungs has not been established.Objectives: Using a nonhuman primate (NHP) model of TB, we sought to assess 3HP treatment-mediated clearance of Mtb infection in latently infected macaques.Methods: Sixteen NHPs were infected via inhalation with ∼10 cfu of Mtb CDC1551, after which asymptomatic animals were either treated with 3HP or left untreated. Pharmacokinetics of the 3HP regimen were measured. Following treatment, animals were coinfected with simian immunodeficiency virus to assess reactivation of LTBI and development of active TB disease.Measurements and Main Results: Fourteen NHPs remained free of clinical signs or microbiological evidence of active TB following infection with Mtb and were subsequently either treated with 3HP (n = 7) or left untreated (n = 7). Untreated NHPs were asymptomatic for 7 months but harbored persistent Mtb infection, as shown by reactivation of latent infection following simian immunodeficiency virus coinfection. However, none of the treated animals developed TB reactivation disease, and they remained without clinical or microbiological evidence of persistent bacilli, suggesting treatment-mediated clearance of bacteria.Conclusions:Mtb can persist in asymptomatic macaques for at least 7 months. Furthermore, 3HP treatment effectively cleared bacteria and prevented reactivation of TB in latently infected macaques.


Subject(s)
Antibiotics, Antitubercular/therapeutic use , Antitubercular Agents/therapeutic use , Isoniazid/therapeutic use , Latent Tuberculosis/drug therapy , Mycobacterium tuberculosis/drug effects , Rifampin/analogs & derivatives , Tuberculosis/drug therapy , Animals , Drug Therapy, Combination , Macaca , Models, Animal , Rifampin/therapeutic use , Treatment Outcome
3.
J Immunol ; 201(3): 888-896, 2018 08 01.
Article in English | MEDLINE | ID: mdl-29914888

ABSTRACT

Human T cells that recognize lipid Ags presented by highly conserved CD1 proteins often express semi-invariant TCRs, but the true diversity of lipid Ag-specific TCRs remains unknown. We use CD1b tetramers and high-throughput immunosequencing to analyze thousands of TCRs from ex vivo-sorted or in vitro-expanded T cells specific for the mycobacterial lipid Ag, glucose monomycolate. Our results reveal a surprisingly diverse repertoire resulting from editing of germline-encoded gene rearrangements analogous to MHC-restricted TCRs. We used a distance-based metric (TCRDist) to show how this diverse TCR repertoire builds upon previously reported conserved motifs by including subject-specific TCRs. In a South African cohort, we show that TCRDist can identify clonal expansion of diverse glucose monomycolate-specific TCRs and accurately distinguish patients with active tuberculosis from control subjects. These data suggest that similar mechanisms govern the selection and expansion of peptide and lipid Ag-specific T cells despite the nonpolymorphic nature of CD1.


Subject(s)
Antigens, CD1/immunology , Lipids/immunology , Receptors, Antigen, T-Cell/immunology , Tuberculosis/immunology , Adolescent , Cell Line, Tumor , Cells, Cultured , Child , Female , Humans , K562 Cells , Male , Mycobacterium/immunology , T-Lymphocytes
4.
J Immunol ; 200(8): 3008-3019, 2018 04 15.
Article in English | MEDLINE | ID: mdl-29540577

ABSTRACT

Antigen-specific CD4 and CD8 T cells are important components of the immune response to Mycobacterium tuberculosis, yet little information is currently known regarding how the breadth, specificity, phenotype, and function of M. tuberculosis-specific T cells correlate with M. tuberculosis infection outcome in humans. To facilitate evaluation of human M. tuberculosis-specific T cell responses targeting multiple different Ags, we sought to develop a high throughput and reproducible T cell response spectrum assay requiring low blood sample volumes. We describe here the optimization and standardization of a microtiter plate-based, diluted whole blood stimulation assay utilizing overlapping peptide pools corresponding to a functionally diverse panel of 60 M. tuberculosis Ags. Using IFN-γ production as a readout of Ag specificity, the assay can be conducted using 50 µl of blood per test condition and can be expanded to accommodate additional Ags. We evaluated the intra- and interassay variability, and implemented testing of the assay in diverse cohorts of M. tuberculosis-unexposed healthy adults, foreign-born adults with latent M. tuberculosis infection residing in the United States, and tuberculosis household contacts with latent M. tuberculosis infection in a tuberculosis-endemic setting in Kenya. The M. tuberculosis-specific T cell response spectrum assay further enhances the immunological toolkit available for evaluating M. tuberculosis-specific T cell responses across different states of M. tuberculosis infection, and can be readily implemented in resource-limited settings. Moreover, application of the assay to longitudinal cohorts will facilitate evaluation of treatment- or vaccine-induced changes in the breadth and specificity of Ag-specific T cell responses, as well as identification of M. tuberculosis-specific T cell responses associated with M. tuberculosis infection outcomes.


Subject(s)
Hematologic Tests/methods , High-Throughput Screening Assays/methods , T-Lymphocytes/immunology , Tuberculosis/blood , Tuberculosis/immunology , Cross-Sectional Studies , Humans , Immunologic Techniques/methods , Longitudinal Studies , Reproducibility of Results
5.
J Immunol ; 199(6): 2069-2080, 2017 09 15.
Article in English | MEDLINE | ID: mdl-28760884

ABSTRACT

Coinfection with HIV is the single greatest risk factor for reactivation of latent Mycobacterium tuberculosis infection (LTBI) and progression to active tuberculosis disease. HIV-associated dysregulation of adaptive immunity by depletion of CD4 Th cells most likely contributes to loss of immune control of LTBI in HIV-infected individuals, although the precise mechanisms whereby HIV infection impedes successful T cell-mediated control of M. tuberculosis have not been well defined. To further delineate mechanisms whereby HIV impairs protective immunity to M. tuberculosis, we evaluated the frequency, phenotype, and functional capacity of M. tuberculosis-specific CD4 T cells in HIV-infected and HIV-uninfected adults with LTBI. HIV infection was associated with a lower total frequency of cytokine-producing M. tuberculosis-specific CD4 T cells, and preferential depletion of a discrete subset of M. tuberculosis-specific IFN-γ+IL-2-TNF-α+ CD4 T cells. M. tuberculosis-specific CD4 T cells in HIV-infected individuals expressed significantly higher levels of Ki67, compared with HIV-uninfected individuals, thus indicating recent activation and turnover of these cells in vivo. The ex vivo proliferative capacity of M. tuberculosis-specific CD4 T cells was markedly impaired in HIV-infected individuals, compared with HIV-uninfected individuals. Moreover, HIV infection was associated with increased M. tuberculosis Ag-induced CD4 T cell death ex vivo, indicating a possible mechanism contributing to impaired proliferative capacity of M. tuberculosis-specific CD4 T cells in HIV-infected individuals. These data provide new insights into the parameters of M. tuberculosis-specific CD4 T cell immunity that are impaired in HIV-infected individuals with LTBI, which may contribute to their increased risk of developing active tuberculosis disease.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , HIV Infections/immunology , HIV-1/immunology , Mycobacterium tuberculosis/immunology , T-Lymphocyte Subsets/immunology , Tuberculosis/immunology , Virus Latency , Adolescent , Adult , Antigens, Bacterial/immunology , Apoptosis , CD4-Positive T-Lymphocytes/microbiology , CD4-Positive T-Lymphocytes/virology , Cell Proliferation , Cells, Cultured , Coinfection , Female , Humans , Immunophenotyping , Interferon-gamma/metabolism , Interleukin-2/metabolism , Lymphocyte Activation , Male , Middle Aged , T-Lymphocyte Subsets/microbiology , T-Lymphocyte Subsets/virology , Virus Latency/immunology , Young Adult
6.
J Infect Dis ; 211(4): 635-40, 2015 Feb 15.
Article in English | MEDLINE | ID: mdl-25205634

ABSTRACT

Human immunodeficiency virus (HIV)-infected individuals with latent Mycobacterium tuberculosis infection have substantially higher rates of progression to active tuberculosis than HIV-uninfected individuals with latent tuberculosis. To explore HIV-induced deficits in M. tuberculosis-specific CD8+ T-cell functions, we compared interferon γ production, degranulation, and proliferation of CD8+ T cells in response to M. tuberculosis peptides (ESAT-6/CFP-10) between HIV-infected (median CD4+ T-cell count, 522 cells/µL; interquartile range, 318-585 cells/µL) and HIV-uninfected individuals with latent tuberculosis from South Africa. We found that M. tuberculosis-specific degranulation and proliferative capacities were impaired in the HIV-infected group. Thus, our results suggest that HIV coinfection compromises CD8+ T-cell functions in latent tuberculosis.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , HIV Infections/complications , HIV Infections/physiopathology , Latent Tuberculosis/complications , Latent Tuberculosis/physiopathology , Adult , CD8-Positive T-Lymphocytes/physiology , Cell Degranulation , Cell Proliferation , Cells, Cultured , Coinfection/epidemiology , Coinfection/immunology , Coinfection/physiopathology , Female , HIV Infections/epidemiology , Humans , Latent Tuberculosis/epidemiology , Latent Tuberculosis/immunology , Leukocytes, Mononuclear , Male , Middle Aged , Mycobacterium tuberculosis/immunology , Young Adult
7.
Clin Infect Dis ; 60(3): 432-7, 2015 Feb 01.
Article in English | MEDLINE | ID: mdl-25362202

ABSTRACT

Immune-based assays are promising tools to help to formulate diagnosis of active tuberculosis. A multiparameter flow cytometry assay assessing T-cell responses specific to Mycobacterium tuberculosis and the combination of both CD4 and CD8 T-cell responses accurately discriminated between active tuberculosis and latent infection.


Subject(s)
Antigens, Bacterial/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Mycobacterium tuberculosis/immunology , Tuberculosis/diagnosis , Adolescent , Adult , Aged , Child , Female , Flow Cytometry , Humans , Male , Middle Aged , Tuberculosis/immunology , Young Adult
8.
Eur J Immunol ; 43(9): 2409-20, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23737382

ABSTRACT

Heterologous prime-boost strategies hold promise for vaccination against tuberculosis. However, the T-cell characteristics required for protection are not known. We proposed that boost vaccines should induce long-lived functional and phenotypic changes to T cells primed by Bacille Calmette Guerin (BCG) and/or natural exposure to mycobacteria. We characterized changes among specific CD4(+) T cells after vaccination with the MVA85A vaccine in adults, adolescents, and children. CD4(+) T cells identified with Ag85A peptide-bearing HLA class II tetramers were characterized by flow cytometry. We also measured proliferative potential and cytokine expression of Ag85A-specific CD4(+) T cells. During the effector phase, MVA85A-induced specific CD4(+) T cells coexpressed IFN-γ and IL-2, skin homing integrins, and the activation marker CD38. This was followed by contraction and a transition to predominantly IL-2-expressing, CD45RA(-) CCR7(+) CD27(+) or CD45RA(+) CCR7(+) CD27(+) specific CD4(+) T cells. These surface phenotypes were similar to Ag85A-specific T cells prior to MVA85A. However, functional differences were observed postvaccination: specific proliferative capacity was markedly higher after 6-12 months than before vaccination. Our data suggest that MVA85A vaccination may modulate Ag85A-specific CD4(+) T-cell function, resulting in greater recall potential. Importantly, surface phenotypes commonly used as proxies for memory T-cell function did not associate with functional effects of vaccination.


Subject(s)
Acyltransferases/immunology , Antigens, Bacterial/immunology , CD4-Positive T-Lymphocytes/immunology , Immunologic Memory , Tuberculosis Vaccines/immunology , Tuberculosis/prevention & control , Viral Vaccines/immunology , ADP-ribosyl Cyclase 1/biosynthesis , Adolescent , Adult , Cell Proliferation , Child , Child, Preschool , Female , Humans , Interferon-gamma/biosynthesis , Interleukin-2/biosynthesis , Leukocyte Common Antigens/metabolism , Lymphocyte Activation , Male , Middle Aged , Mycobacterium tuberculosis/immunology , Receptors, CCR7/metabolism , Tuberculosis/immunology , Tumor Necrosis Factor Receptor Superfamily, Member 7/metabolism , Vaccines, DNA , Young Adult
9.
Eur J Immunol ; 43(6): 1568-77, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23456989

ABSTRACT

Protective immunity to Mycobacterium tuberculosis (Mtb) remains poorly understood and the role of Mtb-specific CD8(+) T cells is controversial. Here we performed a broad phenotypic and functional characterization of Mtb-specific CD8(+) T cells in 326 subjects with latent Mtb infection (LTBI) or active TB disease (TB). Mtb-specific CD8(+) T cells were detected in most (60%) TB patients and few (15%) LTBI subjects but were of similar magnitude. Mtb-specific CD8(+) T cells in LTBI subjects were mostly T EMRA cells (CD45RA(+) CCR7(-)), coexpressing 2B4 and CD160, and in TB patients were mostly TEM cells (CD45RA(-) CCR7(-)), expressing 2B4 but lacking PD-1 and CD160. The cytokine profile was not significantly different in both groups. Furthermore, Mtb-specific CD8(+) T cells expressed low levels of perforin and granulysin but contained granzymes A and B. However, in vitro-expanded Mtb-specific CD8(+) T cells expressed perforin and granulysin. Finally, Mtb-specific CD8(+) T-cell responses were less frequently detected in extrapulmonary TB compared with pulmonary TB patients. Mtb-specific CD8(+) T-cell proliferation was also greater in patients with extrapulmonary compared with pulmonary TB. Thus, the activity of Mtb infection and clinical presentation are associated with distinct profiles of Mtb-specific CD8(+) T-cell responses. These results provide new insights in the interaction between Mtb and the host immune response.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Latent Tuberculosis/immunology , Mycobacterium tuberculosis/immunology , T-Lymphocyte Subsets/immunology , Tuberculosis, Pulmonary/immunology , Acute Disease , Antigens, CD/metabolism , Cell Proliferation , Cells, Cultured , Cytokines/metabolism , GPI-Linked Proteins/metabolism , Humans , Immunophenotyping , Programmed Cell Death 1 Receptor/metabolism , Receptors, Immunologic/metabolism , Signaling Lymphocytic Activation Molecule Family
10.
Am J Respir Crit Care Med ; 188(4): 492-502, 2013 08 15.
Article in English | MEDLINE | ID: mdl-23306546

ABSTRACT

RATIONALE: Tuberculosis (TB) is a major cause of morbidity and mortality worldwide, thus there is an urgent need for novel TB vaccines. OBJECTIVES: We investigated a novel TB vaccine candidate, M72/AS01, in a phase IIa trial of bacille Calmette-Guérin-vaccinated, HIV-uninfected, and Mycobacterium tuberculosis (Mtb)-infected and -uninfected adults in South Africa. METHODS: Two doses of M72/AS01 were administered to healthy adults, with and without latent Mtb infection. Participants were monitored for 7 months after the first dose; cytokine production profiles, cell cycling, and regulatory phenotypes of vaccine-induced T cells were measured by flow cytometry. MEASUREMENTS AND MAIN RESULTS: The vaccine had a clinically acceptable safety profile, and induced robust, long-lived M72-specific T-cell and antibody responses. M72-specific CD4 T cells produced multiple combinations of Th1 cytokines. Analysis of T-cell Ki67 expression showed that most vaccination-induced T cells did not express Th1 cytokines or IL-17; these cytokine-negative Ki67(+) T cells included subsets of CD4 T cells with regulatory phenotypes. PD-1, a negative regulator of activated T cells, was transiently expressed on M72-specific CD4 T cells after vaccination. Specific T-cell subsets were present at significantly higher frequencies after vaccination of Mtb-infected versus -uninfected participants. CONCLUSIONS: M72/AS01 is clinically well tolerated in Mtb-infected and -uninfected adults, induces high frequencies of multifunctional T cells, and boosts distinct T-cell responses primed by natural Mtb infection. Moreover, these results provide important novel insights into how this immunity may be appropriately regulated after novel TB vaccination of Mtb-infected and -uninfected individuals.Clinical trial registered with www.clinicaltrials.gov (NCT 00600782).


Subject(s)
T-Lymphocytes/immunology , Tuberculosis Vaccines/immunology , Adult , CD4 Antigens/metabolism , CD8 Antigens/metabolism , Female , Flow Cytometry , Humans , Immunity, Cellular/immunology , Immunity, Humoral/immunology , Interleukin-17/metabolism , Male , South Africa , Tuberculosis Vaccines/administration & dosage , Young Adult
11.
J Am Vet Med Assoc ; 262(1): 109-116, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38103389

ABSTRACT

Foreign animal disease (FAD) preparedness is a high priority for state and federal governments to ensure the protection of the nation's livestock industry. Highly contagious diseases such as African swine fever (ASF) have been the focus of recent advancements in FAD preparedness, including the development of disease-specific response plans. At the state level, FAD response plans provide a framework to help ensure a rapid and coordinated response that considers the resources and realities of that state; however, preparing a comprehensive plan requires collaboration across multiple agencies and sectors that can be difficult to operationalize. To initiate systematic state-level ASF response plan writing and identify gaps in preparedness, university and industry stakeholders partnered with the Ohio Department of Agriculture and USDA to develop the Ohio African Swine Fever Response Plan Workshop. A linear planning model was used to implement the workshop in May 2021. All planning and workshop activities were conducted fully virtually, prompted by public health restrictions in response to COVID-19. Sixty-four participants, representing multiple sectors and stakeholder groups including state/federal/industry animal health officials, emergency management, environmental protection, and academia, contributed to the workshop. Spanning 3 days, participants identified current response capabilities and areas requiring additional planning for an effective state-level response. The workshop generated recommendations from a multisectoral perspective for subcommittees tasked with developing standard operating procedures for the Ohio ASF Response Plan. The methodology and resources used to plan, implement, and evaluate the workshop are described to provide a model for state-level response planning.


Subject(s)
African Swine Fever , Swine Diseases , Animals , Swine , African Swine Fever/epidemiology , African Swine Fever/prevention & control , Ohio/epidemiology , Public Health , Livestock
12.
Article in English | MEDLINE | ID: mdl-38366732

ABSTRACT

Infection with Mycobacterium tuberculosis (Mtb) in people with HIV (PWH) is associated with depletion of Mtb-specific CD4 T cell responses, increased risk of progression to active tuberculosis (TB) disease, and increased immune activation. Although higher HIV viral loads have been reported in Mtb/HIV co-infection, the extent to which Mtb infection and TB disease impact the frequency and phenotype of HIV-specific T cell responses has not been well described. We enrolled a cohort of PWH in Kenya across a spectrum of Mtb infection states, including those with no evidence of Mtb infection, latent Mtb infection (LTBI), and active pulmonary TB disease, and evaluated the frequency, immune activation, and cytotoxicity phenotype of HIV-specific CD4 and CD8 T cell responses in peripheral blood by flow cytometry. We found evidence of depletion of HIV-specific CD4 and CD8 T cells in people with TB, but not with LTBI. Expression of the immune activation markers human leukocyte antigen-DR isotype (HLA-DR) and Ki67 and of the cytotoxic molecules granzyme B and perforin were increased in total CD4 and CD8 T cell populations in individuals with TB, although expression of these markers by HIV-specific CD4 and CD8 T cells did not differ by Mtb infection status. These data suggest that TB is associated with overall increased T cell activation and cytotoxicity and with depletion of HIV-specific CD4 and CD8 T cells, which may contribute to further impairment of T cell-mediated immune control of HIV replication in the setting of TB.

13.
bioRxiv ; 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38496518

ABSTRACT

CD4 T cells are essential for immunity to M. tuberculosis (Mtb), and emerging evidence indicates that IL-17-producing Th17 cells contribute to immunity to Mtb. While identifying protective T cell effector functions is important for TB vaccine design, T cell antigen specificity is also likely to be important. To identify antigens that induce protective immunity, we reasoned that as in other pathogens, effective immune recognition drives sequence diversity in individual Mtb antigens. We previously identified Mtb genes under evolutionary diversifying selection pressure whose products we term Rare Variable Mtb Antigens (RVMA). Here, in two distinct human cohorts with recent exposure to TB, we found that RVMA preferentially induce CD4 T cells that express RoRγt and produce IL-17, in contrast to 'classical' Mtb antigens that induce T cells that produce IFNγ. Our results suggest that RVMA can be valuable antigens in vaccines for those already infected with Mtb to amplify existing antigen-specific Th17 responses to prevent TB disease.

14.
J Immunol ; 187(5): 2222-32, 2011 Sep 01.
Article in English | MEDLINE | ID: mdl-21775682

ABSTRACT

High Ag load in chronic viral infections has been associated with impairment of Ag-specific T cell responses; however, the relationship between Ag load in chronic Mycobacterium tuberculosis infection and functional capacity of M. tuberculosis-specific T cells in humans is not clear. We compared M. tuberculosis-specific T cell-associated cytokine production and proliferative capacity in peripheral blood from adults with progressively higher mycobacterial loads-that is, persons with latent M. tuberculosis infection (LTBI), with smear-negative pulmonary tuberculosis (TB), and smear-positive TB. Patients with smear-positive TB had decreased polyfunctional IFN-γ(+)IL-2(+)TNF-α(+) and IL-2-producing specific CD4 T cells and increased TNF-α single-positive cells, when compared with smear-negative TB and LTBI. TB patients also had increased frequencies of M. tuberculosis-specific CD8 T cells, compared with LTBI. M. tuberculosis-specific CD4 and CD8 T cell proliferative capacity was profoundly impaired in individuals with smear-positive TB, and correlated positively with ex vivo IFN-γ(+)IL-2(+)TNF-α(+) CD4 T cells, and inversely with TNF-α single-positive CD4 T cells. During 6 mo of anti-TB treatment, specific IFN-γ(+)IL-2(+)TNF-α(+) CD4 and CD8 T cells increased, whereas TNF-α and IFN-γ single-positive T cells decreased. These results suggest progressive impairment of M. tuberculosis-specific T cell responses with increasing mycobacterial load and recovery of responses during therapy. Furthermore, these data provide a link between specific cytokine-producing subsets and functional capacity of M. tuberculosis-specific T cells, and between the presence of specific CD8 T cells ex vivo and active TB disease. These data have potentially significant applications for the diagnosis of TB and for the identification of T cell correlates of TB disease progression.


Subject(s)
Bacterial Load , T-Lymphocyte Subsets/immunology , T-Lymphocytes/immunology , Tuberculosis/immunology , Tuberculosis/microbiology , Adolescent , Adult , Cell Proliferation , Cell Separation , Cytokines/biosynthesis , Disease Progression , Female , Flow Cytometry , Humans , Male , Middle Aged , Mycobacterium tuberculosis/immunology , Young Adult
15.
Tuberculosis (Edinb) ; 139: 102328, 2023 03.
Article in English | MEDLINE | ID: mdl-36871409

ABSTRACT

Following exposure to Mycobacterium tuberculosis (Mtb), a coordinated host response comprising both pro- and anti-inflammatory cytokines is critical for pathogen control. Although tuberculosis (TB) remains the leading cause of death among people with human immunodeficiency virus (HIV), the impact of HIV infection on Mtb-specific immune responses remains unclear. In this cross-sectional study of TB-exposed household contacts with and without HIV, we collected remaining supernatant from interferon-gamma release assay (IGRA) testing (QuantiFERON-TB Gold Plus [QFT-Plus]) and measured Mtb-specific pro-inflammatory, anti-inflammatory, and regulatory cytokine responses with a multiplex assay of 11 analytes. While people with HIV had lower responses to mitogen stimulation for some cytokines (granulocyte-macrophage colony-stimulating factor [GM-CSF], interleukin [IL]-2, IL-10, IL-17A, IL-22), there was no difference in cytokine levels for people with and without HIV following stimulation with Mtb-specific antigens. Future studies are necessary to explore whether changes in Mtb-specific cytokine responses over time are associated with distinct clinical outcomes following exposure to TB.


Subject(s)
HIV Infections , Latent Tuberculosis , Mycobacterium tuberculosis , Tuberculosis , Humans , Cytokines , Cross-Sectional Studies , Interferon-gamma , Antigens, Bacterial , Tuberculosis/microbiology , Interferon-gamma Release Tests , Latent Tuberculosis/microbiology
17.
Nature ; 443(7109): 350-4, 2006 Sep 21.
Article in English | MEDLINE | ID: mdl-16921384

ABSTRACT

Functional impairment of T cells is characteristic of many chronic mouse and human viral infections. The inhibitory receptor programmed death 1 (PD-1; also known as PDCD1), a negative regulator of activated T cells, is markedly upregulated on the surface of exhausted virus-specific CD8 T cells in mice. Blockade of this pathway using antibodies against the PD ligand 1 (PD-L1, also known as CD274) restores CD8 T-cell function and reduces viral load. To investigate the role of PD-1 in a chronic human viral infection, we examined PD-1 expression on human immunodeficiency virus (HIV)-specific CD8 T cells in 71 clade-C-infected people who were naive to anti-HIV treatments, using ten major histocompatibility complex (MHC) class I tetramers specific for frequently targeted epitopes. Here we report that PD-1 is significantly upregulated on these cells, and expression correlates with impaired HIV-specific CD8 T-cell function as well as predictors of disease progression: positively with plasma viral load and inversely with CD4 T-cell count. PD-1 expression on CD4 T cells likewise showed a positive correlation with viral load and an inverse correlation with CD4 T-cell count, and blockade of the pathway augmented HIV-specific CD4 and CD8 T-cell function. These data indicate that the immunoregulatory PD-1/PD-L1 pathway is operative during a persistent viral infection in humans, and define a reversible defect in HIV-specific T-cell function. Moreover, this pathway of reversible T-cell impairment provides a potential target for enhancing the function of exhausted T cells in chronic HIV infection.


Subject(s)
Antigens, CD/metabolism , Apoptosis Regulatory Proteins/metabolism , CD8-Positive T-Lymphocytes/pathology , CD8-Positive T-Lymphocytes/virology , HIV Infections/metabolism , HIV Infections/pathology , HIV/physiology , Apoptosis Regulatory Proteins/antagonists & inhibitors , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Disease Progression , Gene Expression , HIV Infections/immunology , HIV Infections/virology , Histocompatibility Antigens Class I/immunology , Histocompatibility Antigens Class I/metabolism , Humans , Interferon-gamma/immunology , Interferon-gamma/metabolism , Programmed Cell Death 1 Receptor , Up-Regulation
18.
Data Brief ; 45: 108639, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36425993

ABSTRACT

The summary data presented in this paper describes beekeeping practices, use of natural resources and economic attributes associated with honey bee products, native flora and environmental challenges relating to apiary sites. Despite being a well-established industry, information and data about productivity and the behavior of beekeepers, particularly those who migrate across the state of Western Australia, is lacking. We developed an online quantitative survey, the Natural Resources for Beekeepers Questionnaire (Western Australia) 2020-21, the first comprehensive, spatially referenced survey of beekeepers in Western Australia since 1990. It is also the first survey of small-scale amateur beekeepers that estimates their supply to the local honey market. For commercial beekeepers, a focus of the survey was to estimate the value of apiary sites and the productivity of migratory beekeepers. The data gives measures related to the production system and profitability of the Western Australian beekeeping industry, focusing on the 2019-2020 season and historical production. It includes tables describing memberships and certification; years beekeeping; hive types; apiary site availability, productivity, use, exchange and value; logistics; pollination services; honey bee products, sales and distribution; yields by season and site; targeted flora and commercial significance; recovery after bush fire and logging; labour details; operating costs; and asset values. The dataset in this paper is a subset of the survey results as aggregated summary statistics, categorized by type of beekeeper (Backyard, Hobbyist-Amateur and Commercial) and across eight regions (IBRA7 - Interim Biogeographic Regionalization for Australia). The online survey questionnaire is provided with this paper. Access to the survey offers the opportunity for reproducibility of a complex online questionnaire in the future and/or for other regions. This dataset will allow a more comprehensive assessment of the implications of natural resource management decisions in the future and the potential for strategic development of the beekeeping industry.

19.
J Pediatric Infect Dis Soc ; 11(Supplement_3): S110-S116, 2022 Oct 31.
Article in English | MEDLINE | ID: mdl-36314550

ABSTRACT

Tuberculosis (TB) is a leading cause of global child mortality. Until the turn of the 21st century, Mycobacterium bovis bacille Calmette-Guerin (BCG) was the only vaccine to prevent TB. The pediatric TB vaccine pipeline has advanced in the past decade to include the evaluation of novel whole cell vaccines to replace infant BCG and investigation of subunit and whole cell vaccines to boost TB immunity during adolescence. We describe the history of BCG, current TB vaccine candidates in clinical trials, and the challenges and opportunities for future TB vaccine research in children. Children are a critical target population for TB vaccines, and expansion of the pediatric TB vaccine pipeline is urgently needed to end the TB pandemic.


Subject(s)
Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculosis Vaccines , Tuberculosis , Humans , Child , Tuberculosis Vaccines/therapeutic use , BCG Vaccine , Tuberculosis/prevention & control , Tuberculosis/epidemiology
20.
Diabetes Care ; 45(4): 880-887, 2022 04 01.
Article in English | MEDLINE | ID: mdl-35168250

ABSTRACT

OBJECTIVE: In cross-sectional U.S. studies, patients with diabetes had twice the prevalence of latent tuberculosis infection (LTBI) compared with those without diabetes. However, whether LTBI contributes to diabetes risk is unknown. We used longitudinal data to determine if LTBI is associated with increased diabetes incidence. RESEARCH DESIGN AND METHODS: We conducted a retrospective cohort study among U.S. Veterans receiving care in the Veterans Health Administration from 2000 to 2015. Eligibility included all patients without preexisting diabetes who received a tuberculin skin test (TST) or interferon-γ release assay (IGRA). We excluded patients with a history of active TB and those diagnosed with diabetes before or within 2 years after LTBI testing. Patients were followed until diabetes diagnosis, death, or 2015. LTBI was defined as TST or IGRA positive. Incident diabetes was defined by use of ICD-9 codes in combination with a diabetes drug prescription. RESULTS: Among 574,113 eligible patients, 5.3% received both TST/IGRA, 79.1% received TST only, and 15.6% received IGRA only. Overall, 6.6% had LTBI, and there were 2,535,149 person-years (PY) of follow-up after LTBI testing (median 3.2 years). The diabetes incidence rate (per 100,000 PY) was greater in patients with LTBI compared with those without (1,012 vs. 744; hazard ratio [HR] 1.4 [95% CI 1.3-1.4]). Increased diabetes incidence persisted after adjustment for covariates (adjusted HR [aHR] 1.2 [95% CI 1.2-1.3]) compared with those without LTBI. Among patients with LTBI, diabetes incidence was similar in those treated for LTBI compared with those who were not treated (aHR 1.0 [95% CI 0.9-1.1]). CONCLUSIONS: Comprehensive longitudinal data indicate that LTBI is associated with increased diabetes incidence. These results have implications for people with LTBI, ∼25% of the global population.


Subject(s)
Diabetes Mellitus , Latent Tuberculosis , Cross-Sectional Studies , Diabetes Mellitus/epidemiology , Humans , Interferon-gamma Release Tests/methods , Latent Tuberculosis/diagnosis , Latent Tuberculosis/drug therapy , Latent Tuberculosis/epidemiology , Retrospective Studies
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