RESUMO
The study revealed no effects of pregnancy and childbirth on the course of tuberculosis in female BALB/c mice after aerosol infection with Mycobacterium tuberculosis. However, we demonstrated a negative effect of tuberculosis infection on the fertility of infected females, which manifested in a longer period from mating to pregnancy and in a smaller litter size. Impaired reproductive function in response to the effect of the systemic infectious process was accompanied by the development of immunosuppression confirmed by an immunological test (delayed-type hypersensitivity to tuberculin) and the formation of genital tract dysbiosis during pregnancy and postpartum period.
Assuntos
Fertilidade , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis , Tuberculose , Animais , Feminino , Camundongos , Fertilidade/fisiologia , Gravidez , Mycobacterium tuberculosis/patogenicidade , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Tuberculose/microbiologia , Disbiose/microbiologia , Disbiose/imunologia , Hipersensibilidade Tardia/imunologia , Tamanho da Ninhada de VivíparosRESUMO
INTRODUCTION: The large reservoir of tuberculosis (TB) infections is one of the main reasons for the persistent incidence of TB. Accurate diagnostic tests are crucial to correctly identify and treat people with TB infection, which is vital to eliminate TB globally. The rdESAT-6 and rCFP-10 (Cy-Tb) injection ('Cy-Tb'), a TB-specific antigen skin test and STANDARD F TB-Feron FIA ('Standard F TB') measuring interferon-gamma by fluorescence immunoassay assay are two novel tools for the diagnosis of TB infection which offer advantages compared with current tests in low-resource settings and reduced costs to both health systems and TB-affected people. The proposed study aims to evaluate the diagnostic accuracy of these two new tests for TB infection diagnosis. METHODS AND ANALYSIS: This cross-sectional study aims to assess the diagnostic accuracy for TB infection of the Cy-Tb skin test and Standard F TB assay (investigational tests) compared with the QuantiFERON-TB Gold Plus (QFT-Plus) assay as the immunological reference standard. Three different cohorts of study participants will be recruited at the Vietnam National Lung Hospital: adults with bacteriologically confirmed pulmonary TB (n=100), household contacts of people with TB (n=200) and people without TB infection (n=50). All consenting participants will undergo simultaneous testing with Cy-Tb, Standard F TB and QFT-Plus. The primary endpoint is the diagnostic accuracy of the Cy-Tb skin test and Standard F TB assay, expressed as sensitivity and specificity against the reference standard. ETHICS AND DISSEMINATION: Ethical approval was granted by the Vietnam National Lung Hospital Institutional Review Board (65/23/CN-HDDD-BVPTU) and the Swedish Ethical Review Authority (Dnr 2023-04271-01). Study results will be disseminated to the scientific community and policymakers through scientific publications. TRIAL REGISTRATION NUMBER: NCT06221735.
Assuntos
Testes de Liberação de Interferon-gama , Teste Tuberculínico , Tuberculose , Adulto , Humanos , Antígenos de Bactérias/análise , Estudos Transversais , Testes de Liberação de Interferon-gama/métodos , Mycobacterium tuberculosis/isolamento & purificação , Mycobacterium tuberculosis/imunologia , Sensibilidade e Especificidade , Teste Tuberculínico/métodos , Tuberculose/diagnóstico , Tuberculose Pulmonar/diagnóstico , Vietnã , Projetos de PesquisaRESUMO
Tuberculosis (TB), caused by Mycobacterium tuberculosis (M. tb), is a major global health issue, with around 10 million new cases annually. Advances in TB immunology have improved our understanding of host signaling pathways, leading to innovative therapeutic strategies. Inflammasomes, protein complexes organized by cytosolic pattern recognition receptors (PRRs), play a crucial role in the immune response to M. tb by activating caspase 1, which matures proinflammatory cytokines IL1ß and IL18. While inflammation is necessary to fight infection, excessive or dysregulated inflammation can cause tissue damage, highlighting the need for precise inflammasome regulation. Drug-resistant TB strains have spurred research into adjunctive host-directed therapies (HDTs) that target inflammasome pathways to control inflammation. Canonical and non-canonical inflammasome pathways can trigger excessive inflammation, leading to immune system exhaustion and M. tb spread. Novel HDT interventions can leverage precision medicine by tailoring treatments to individual inflammasome responses. Studies show that medicinal plant derivatives like silybin, andrographolide, and micheliolide and small molecules such as OLT1177, INF39, CY-09, JJ002, Ac-YVAD-cmk, TAK-242, and MCC950 can modulate inflammasome activation. Molecular tools like gene silencing and knockouts may also be used for severe TB cases. This review explores these strategies as potential adjunctive HDTs in fighting TB.
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Inflamassomos , Mycobacterium tuberculosis , Tuberculose , Humanos , Inflamassomos/metabolismo , Inflamassomos/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Animais , Antituberculosos/uso terapêutico , Antituberculosos/farmacologia , Transdução de Sinais , Interações Hospedeiro-Patógeno/imunologiaRESUMO
Introduction. Tuberculosis (TB), an infectious disease caused by Mycobacterium tuberculosis (M. tb), remains a significant global public health concern. It is crucial to develop more effective vaccines for TB in order to achieve global control of the disease. Extracellular vesicles (EVs) are spherical membrane-bound structures released by pathogens and host cells. During the course of an infection, both pathogen- and host-derived EVs are produced and play important roles in determining the course of the infection. EVs offer intriguing tools as potential vaccines due to their ability to deliver multiple pathogen or host antigens.Hypothesis /Gap Statement. We hypothesized that EVs derived from M. tb and EVs from M. tb-infected macrophages may serve as potential vaccine candidates against M. tb infection.Aim. This study aims to compare the immunogenicity and immune protection between M. tb EVs and M. tb-infected macrophage-derived EVs.Methodology. In this study, EVs were extracted from culture supernatants of M. tb and M. tb-infected macrophages, respectively. Mass spectrometry was employed to explore the antigen composition of H37Rv-Mφ-EVs and H37Rv-EVs. Cytokine profiling and antibody response assays were used to analyse the immunogenicity offered by EVs. Additionally, we used histological examination to evaluate and protective efficacy of the EVs.Results. Our results demonstrated that mice immunized by EVs released from M. tb-infected macrophages induced stronger inflammatory cytokine response than M. tb. Moreover, EVs from M. tb-infected macrophages reinforced T-cell activation and antibody response compared to M. tb EVs. Proteomic analysis revealed that EVs from M. tb-infected macrophages containing immunodominant cargos have stronger binding ability with major histocompatibility complex molecules, which may contribute to the protection from M. tb infection. Indeed, immunization of EVs released from M. tb-infected macrophages significantly reduced the bacterial load and better protection against M. tb infection than EVs from M. tb. Importantly, the selected antigens (Ag85B, ESAT-6 and the Rv0580c) from EVs of M. tb-infected macrophages exhibited effective immunogenicity.Conclusion. Our results suggested that EVs derived from M. tb-infected macrophages might serve as a proper antigenic library for vaccine candidates against M. tb challenge.
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Antígenos de Bactérias , Vesículas Extracelulares , Macrófagos , Mycobacterium tuberculosis , Vacinas contra a Tuberculose , Tuberculose , Vesículas Extracelulares/imunologia , Mycobacterium tuberculosis/imunologia , Animais , Antígenos de Bactérias/imunologia , Vacinas contra a Tuberculose/imunologia , Vacinas contra a Tuberculose/administração & dosagem , Camundongos , Macrófagos/imunologia , Macrófagos/microbiologia , Tuberculose/prevenção & controle , Tuberculose/imunologia , Tuberculose/microbiologia , Citocinas/metabolismo , FemininoRESUMO
Tuberculosis (TB) remains one of the gravest global health challenges. Mycobacterium tuberculosis (M. tuberculosis), the causative agent, employs sophisticated immune evasion and pathogenesis strategies. Its capability to thrive within immune cells and incite robust inflammatory responses prolongs infection and dissemination. Mycobacterial advanced adaptations facilitate navigation through the human immune system and present a variable antigenic profile throughout different infection stages. Investigating these strategies unfolds targeted approaches to effective vaccine development against TB. This review delves into the most advanced and exhaustive insights into the immune evasion tactics and pathogenic processes of M. tuberculosis across various infection stages. The knowledge distilled from this analysis holds the promise of guiding the creation of innovative TB vaccines and translating theoretical groundwork into practical immunological defenses.
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Antígenos de Bactérias , Mycobacterium tuberculosis , Vacinas contra a Tuberculose , Tuberculose , Humanos , Vacinas contra a Tuberculose/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Tuberculose/prevenção & controle , Antígenos de Bactérias/imunologia , Animais , Desenvolvimento de Vacinas , Evasão da Resposta Imune , Interações Hospedeiro-Patógeno/imunologiaRESUMO
The limitations of TB treatment are the long duration and immune-dampening effects of anti-tuberculosis therapy. The Cell wall plays a crucial role in survival and virulence; hence, enzymes involved in its biosynthesis are good therapeutic targets. Here, we identify Mycobacterium tuberculosis (Mtb) GlmM, (GlmMMtb) engaged in the UDP-GlcNAc synthesis pathway as an essential enzyme. We generated a conditional knockdown strain, Rv-glmMkD using the CRISPR interference-mediated gene silencing approach. Depletion of GlmMMtb affects the morphology and thickness of the cell wall. The Rv-glmMkD strain attenuated Mtb survival in vitro, in the host macrophages (ex vivo), and in a murine mice infection model (in vivo). Results suggest that the depletion of GlmMMtb induces M1 macrophage polarization, prompting a pro-inflammatory cytokine response, apparent from the upregulation of activation markers, including IFNÉ£ and IL-17 that resists the growth of Mtb. These observations provide a rationale for exploring GlmMMtb as a potential therapeutic target.
Assuntos
Proteínas de Bactérias , Macrófagos , Mycobacterium tuberculosis , Tuberculose , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/patogenicidade , Animais , Camundongos , Tuberculose/imunologia , Tuberculose/microbiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Macrófagos/imunologia , Macrófagos/microbiologia , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Feminino , Interações Hospedeiro-Patógeno/imunologia , Modelos Animais de Doenças , HumanosRESUMO
Tuberculous meningitis, a severe form of tuberculosis caused by Mycobacterium tuberculosis (BK), remains a major public health challenge worldwide. In addition to the complex mechanisms of the innate and adaptive immune response against Mycobacterium tuberculosis, there is a crucial genetic dimension to consider. Individuals with specific genetic variations may have altered immune responses that make them more susceptible to this form of tuberculosis. Genetic mutations in genes encoding surface receptors, adaptor proteins, kinases, transcription factors, nucleic receptors and other molecules involved in cellular interactions and molecular mechanisms have been associated with susceptibility to TB. Understanding the molecular mechanisms of immune interactions in host response to Mycobacterium tuberculosis is crucial to understanding the genetic dimension in susceptibility to tuberculosis, particularly its dreaded form of tuberculous meningitis. The aim of this update is to explore in details the key interactions between the main players in innate and adaptive immunity during infection with Mycobacterium tuberculosis, with particular emphasis on the genetic factors associated with susceptibility to tuberculosis, especially its dreaded form of tuberculous meningitis.
Assuntos
Predisposição Genética para Doença , Mycobacterium tuberculosis , Tuberculose Meníngea , Humanos , Tuberculose Meníngea/genética , Tuberculose Meníngea/imunologia , Mycobacterium tuberculosis/imunologia , Imunidade Inata/genética , Imunidade Adaptativa/genéticaRESUMO
Introduction: Neutrophils play a complex and important role in the immunopathology of TB. Data suggest they are protective during early infection but become a main driver of immunopathology if infection progresses to active disease. Neutrophils are now recognized to exist in functionally diverse states, but little work has been done on how neutrophil states or subsets are skewed in TB disease. Methods: To address this, we carried out comprehensive phenotyping by flow cytometry of neutrophils in the blood and airways of individuals with active pulmonary TB with and without HIV co-infection recruited in Durban, South Africa. Results: Active TB was associated with a profound skewing of neutrophils in the blood toward phenotypes associated with activation and apoptosis, reduced phagocytosis, reverse transmigration, and immune regulation. This skewing was also apparently in airway neutrophils, particularly the regulatory subsets expressing PDL-1 and LOX-1. HIV co-infection did not impact neutrophil subsets in the blood but was associated with a phenotypic change in the airways and a reduction in key neutrophil functional proteins cathelicidin and arginase 1. Discussion: Active TB is associated with profound skewing of blood and airway neutrophils and suggests multiple mechanisms by which neutrophils may exacerbate the immunopathology of TB. These data indicate potential avenues for reducing neutrophil-mediated lung pathology at the point of diagnosis.
Assuntos
Infecções por HIV , Imunofenotipagem , Neutrófilos , Tuberculose Pulmonar , Humanos , Neutrófilos/imunologia , Masculino , Adulto , Feminino , Infecções por HIV/imunologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/patologia , África do Sul , Coinfecção/imunologia , Pessoa de Meia-Idade , Fenótipo , Citometria de Fluxo , Adulto Jovem , Mycobacterium tuberculosis/imunologiaRESUMO
OBJECTIVE: To evaluate the auxiliary diagnostic value of T cells spot test of Mycobacterium tuberculosis infection (T-SPOT.TB) for pulmonary and extra-pulmonary tuberculosis among the elderly. METHODS: A total of 173 elderly patients at ages of 60 years and older and with suspected tuberculosis that were admitted to People's Hospital of Xinjiang Uygur Autonomous Region during the period from October 2022 through February 2024 were enrolled, and all patients underwent T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests. The etiological tests of MTB served as a gold standard, and the diagnostic values of T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests for pulmonary and extra-pulmonary tuberculosis were compared among the elderly patients. RESULTS: Of the 173 elderly patients suspected of tuberculosis, there were 44 patients definitely diagnosed with pulmonary tuberculosis, 30 cases with extra-pulmonary tuberculosis, and 99 cases without tuberculosis. The sensitivities of T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests were 86.5%, 27.0% and 54.1% for diagnosis of tuberculosis. The sensitivities of T-SPOT.TB were 86.4% and 86.7% for diagnosis of pulmonary tuberculosis and extra-pulmonary tuberculosis, with an 80.8% specificity for diagnosis of tuberculosis. The sensitivities of GeneXpert MTB/RIF were 56.8% and 50.0% for diagnosis of pulmonary tuberculosis and extra-pulmonary tuberculosis, with a 100.0% specificity each, and the sensitivities of acid fast staining were 31.8% and 20.0% for diagnosis of pulmonary tuberculosis and extra-pulmonary tuberculosis, with a 100.0% specificity each. In addition, the areas under the receiver operating characteristic curve were 0.836, 0.635 and 0.770 for diagnosis of tuberculosis with T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests among the elderly patients, respectively. CONCLUSIONS: T-SPOT.TB has a high auxiliary diagnostic value for both pulmonary and extra-pulmonary tuberculosis among elderly patients.
Assuntos
Mycobacterium tuberculosis , Tuberculose Pulmonar , Humanos , Idoso , Mycobacterium tuberculosis/isolamento & purificação , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/fisiologia , Masculino , Feminino , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/microbiologia , Tuberculose Pulmonar/imunologia , Pessoa de Meia-Idade , Tuberculose/diagnóstico , Tuberculose/microbiologia , Tuberculose/imunologia , Idoso de 80 Anos ou mais , Linfócitos T/imunologia , Sensibilidade e Especificidade , Tuberculose ExtrapulmonarRESUMO
Background: Tuberculosis (TB) persists as a global health challenge, with its treatment hampered by the side effects of long-term combination drug therapies and the growing issue of drug resistance. Therefore, the development of novel therapeutic strategies is critical. This study focuses on the role of immune checkpoint molecules (ICs) and functions of CD8+ T cells in the search for new potential targets against TB. Methods: We conducted differential expression genes analysis and CD8+ T cell functional gene analysis on 92 TB samples and 61 healthy individual (HI) samples from TB database GSE83456, which contains data on 34,603 genes. The GSE54992 dataset was used to validated the findings. Additionally, a cluster analysis on single-cell data from primates infected with mycobacterium tuberculosis and those vaccinated with BCG was performed. Results: The overexpression of LAG-3 gene was found as a potentially important characteristic of both pulmonary TB (PTB) and extrapulmonary TB (EPTB). Further correlation analysis showed that LAG-3 gene was correlated with GZMB, perforin, IL-2 and IL-12. A significant temporal and spatial variation in LAG-3 expression was observed in T cells and macrophages during TB infection and after BCG vaccination. Conclusion: LAG-3 was overexpressed in TB samples. Targeting LAG-3 may represent a potential therapeutic target for tuberculosis.
Assuntos
Antígenos CD , Linfócitos T CD8-Positivos , Proteína do Gene 3 de Ativação de Linfócitos , Mycobacterium tuberculosis , Tuberculose , Humanos , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/genética , Linfócitos T CD8-Positivos/imunologia , Tuberculose/imunologia , Tuberculose/microbiologia , Animais , Antígenos CD/genética , Vacina BCG/imunologia , Macrófagos/imunologia , Macrófagos/microbiologia , Interleucina-2/metabolismo , Interleucina-2/genética , Perfilação da Expressão Gênica , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia , Interleucina-12/genética , Interleucina-12/metabolismo , Perforina/genética , Perforina/metabolismo , MasculinoRESUMO
Tuberculosis (TB) remains a significant global health challenge, with approximately 1.5 million deaths per year. The Bacillus Calmette-Guérin (BCG) vaccine against TB is used in infants but shows variable protection. Here, we introduce a novel approach using a double gene knockout mutant (DKO) from wild-type Mycobacterium tuberculosis (Mtb) targeting fbpA and sapM genes. DKO exhibited enhanced anti-TB gene expression in mouse antigen-presenting cells, activating autophagy and inflammasomes. This heightened immune response improved ex vivo antigen presentation to T cells. Subcutaneous vaccination with DKO led to increased protection against TB in wild-type C57Bl/6 mice, surpassing the protection observed in caspase 1/11-deficient C57Bl/6 mice and highlighting the critical role of inflammasomes in TB protection. The DKO vaccine also generated stronger and longer-lasting protection than the BCG vaccine in C57Bl/6 mice, expanding both CD62L-CCR7-CD44+/-CD127+ effector T cells and CD62L+CCR7+/-CD44+CD127+ central memory T cells. These immune responses correlated with a substantial ≥ 1.7-log10 reduction in Mtb lung burden. The DKO vaccine represents a promising new approach for TB immunization that mediates protection through autophagy and inflammasome pathways.
Assuntos
Macrófagos , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis , Vacinas contra a Tuberculose , Tuberculose , Animais , Mycobacterium tuberculosis/imunologia , Camundongos , Macrófagos/imunologia , Tuberculose/imunologia , Tuberculose/prevenção & controle , Vacinas contra a Tuberculose/imunologia , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/genética , Inflamassomos/imunologia , Feminino , Vacina BCG/imunologia , Autofagia/imunologia , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/genética , Modelos Animais de DoençasRESUMO
Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) has recently gained prominence for its ability to provide molecular and spatial information in tissue sections. This technology has the potential to uncover novel insights into proteins and other molecules in biological and immunological pathways activated along diseases with a complex host-pathogen interaction, such as animal tuberculosis. Thus, the present study conducted a data analysis of protein signature in granulomas of cattle and pigs naturally infected with the Mycobacterium tuberculosis complex (MTC), identifying biological and immunological signaling pathways activated throughout the disease. Lymph nodes from four pigs and four cattle, positive for the MTC by bacteriological culture and/or real-time PCR, were processed for histopathological examination and MALDI-MSI. Protein identities were assigned using the MaTisse database, and protein-protein interaction networks were visualized using the STRING database. Gene Ontology (GO) analysis was carried out to determine biological and immunological signaling pathways in which these proteins could participate together with Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Distinct proteomic profiles between cattle and pig granulomas were displayed. Noteworthy, the GO analysis revealed also common pathways among both species, such as "Complement activation, alternative pathway" and "Tricarboxylic acid cycle", which highlight pathways that are conserved among different species infected by the MTC. In addition, species-specific terms were identified in the current study, such as "Natural killer cell degranulation" in cattle or those related to platelet and neutrophil recruitment and activation in pigs. Overall, this study provides insights into the immunopathogenesis of tuberculosis in cattle and pigs, opening new areas of research and highlighting the importance, among others, of the complement activation pathway and the regulation of natural killer cell- and neutrophil-mediated immunity in this disease.
Assuntos
Granuloma , Mycobacterium tuberculosis , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tuberculose , Animais , Suínos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária , Bovinos , Proteômica/métodos , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Tuberculose/veterinária , Tuberculose/microbiologia , Tuberculose/metabolismo , Granuloma/imunologia , Granuloma/microbiologia , Granuloma/metabolismo , Granuloma/veterinária , Doenças dos Suínos/imunologia , Doenças dos Suínos/microbiologia , Mapas de Interação de Proteínas , Interações Hospedeiro-Patógeno/imunologia , Proteoma , Transdução de SinaisRESUMO
At the beginning of the COVID-19 pandemic those with underlying chronic lung conditions, including tuberculosis (TB), were hypothesized to be at higher risk of severe COVID-19 disease. However, there is inconclusive clinical and preclinical data to confirm the specific risk SARS-CoV-2 poses for the millions of individuals infected with Mycobacterium tuberculosis (M.tb). We and others have found that compared to singly infected mice, mice co-infected with M.tb and SARS-CoV-2 leads to reduced SARS-CoV-2 severity compared to mice infected with SARS-CoV-2 alone. Consequently, there is a large interest in identifying the molecular mechanisms responsible for the reduced SARS-CoV-2 infection severity observed in M.tb and SARS-CoV-2 co-infection. To address this, we conducted a comprehensive characterization of a co-infection model and performed mechanistic in vitro modeling to dynamically assess how the innate immune response induced by M.tb restricts viral replication. Our study has successfully identified several cytokines that induce the upregulation of anti-viral genes in lung epithelial cells, thereby providing protection prior to challenge with SARS-CoV-2. In conclusion, our study offers a comprehensive understanding of the key pathways induced by an existing bacterial infection that effectively restricts SARS-CoV-2 activity and identifies candidate therapeutic targets for SARS-CoV-2 infection.
Assuntos
COVID-19 , Coinfecção , Imunidade Inata , Mycobacterium tuberculosis , SARS-CoV-2 , COVID-19/imunologia , Animais , Mycobacterium tuberculosis/imunologia , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Camundongos , Coinfecção/imunologia , Humanos , Tuberculose/imunologia , Tuberculose/microbiologia , Citocinas/metabolismo , Citocinas/imunologia , Modelos Animais de Doenças , Índice de Gravidade de Doença , Pulmão/imunologia , Pulmão/virologia , Pulmão/microbiologia , Pulmão/patologia , Replicação Viral , Camundongos Endogâmicos C57BL , FemininoRESUMO
Tuberculosis (TB), caused by Mycobacterium tuberculosis, remains the leading cause of mortality by a single infectious agent in the world. M. tuberculosis infection could also result in clinical chronic infection, known as latent TB infection (LTBI). Compared to the current limited treatment, several subunit vaccines showed immunotherapeutic effects and were included in clinical trials. In this study, a subunit vaccine of Ag85B with a novel mucosal adjuvant c-di-AMP (Ag85B:c-di-AMP) was delivered intranasally to a persistent M. tuberculosis H37Ra infection mouse model, which also presented the asymptomatic characteristics of LTBI. Compared with Ag85B immunization, Ag85B:c-di-AMP vaccination induced stronger humoral immune responses, significantly higher CD4+ T cells recruitment, enhanced Th1/Th2/Th17 profile response in the lung, decreased pathological lesions of the lung, and reduced M. tuberculosis load in mice. Taken together, Ag85B:c-di-AMP mucosal route immunization provided an immunotherapeutic effect on persistent M. tuberculosis H37Ra infection, and c-di-AMP, as a promising potential mucosal adjuvant, could be further used in therapeutic or prophylactic vaccine strategies for persistent M. tuberculosis infection as well as LTBI.
Assuntos
Adjuvantes Imunológicos , Modelos Animais de Doenças , Mycobacterium tuberculosis , Vacinas contra a Tuberculose , Animais , Adjuvantes Imunológicos/administração & dosagem , Vacinas contra a Tuberculose/imunologia , Vacinas contra a Tuberculose/administração & dosagem , Mycobacterium tuberculosis/imunologia , Camundongos , Feminino , Antígenos de Bactérias/imunologia , Aciltransferases/imunologia , Vacinas de Subunidades Antigênicas/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Proteínas de Bactérias/imunologia , Tuberculose/imunologia , Tuberculose/prevenção & controle , Tuberculose Latente/imunologia , Camundongos Endogâmicos BALB C , Administração IntranasalRESUMO
To investigate how host and pathogen diversity govern immunity against Mycobacterium tuberculosis (Mtb), we performed a large-scale screen of vaccine-mediated protection against aerosol Mtb infection using three inbred mouse strains [C57BL/6 (B6), C3HeB/FeJ (C3H), Balb/c x 129/SvJ (C129F1)] and three Mtb strains (H37Rv, CDC1551, SA161) representing two lineages and distinct virulence properties. We compared three protective modalities, all of which involve inoculation with live mycobacteria: Bacillus Calmette-Guérin (BCG), the only approved TB vaccine, delivered either subcutaneously or intravenously, and concomitant Mtb infection (CoMtb), a model of pre-existing immunity in which a low-level Mtb infection is established in the cervical lymph node following intradermal inoculation. We examined lung bacterial burdens at early (Day 28) and late (Day 98) time points after aerosol Mtb challenge and histopathology at Day 98. We observed substantial heterogeneity in the reduction of bacterial load afforded by these modalities at Day 28 across the combinations and noted a strong positive correlation between bacterial burden in unvaccinated mice and the degree of protection afforded by vaccination. Although we observed variation in the degree of reduction in bacterial burdens across the nine mouse/bacterium strain combinations, virtually all protective modalities performed similarly for a given strain-strain combination. We also noted dramatic variation in histopathology changes driven by both host and bacterial genetic backgrounds. Vaccination improved pathology scores for all infections except CDC1551. However, the most dramatic impact of vaccination on lesion development occurred for the C3H-SA161 combination, where vaccination entirely abrogated the development of the large necrotic lesions that arise in unvaccinated mice. In conclusion, we find that substantial TB heterogeneity can be recapitulated by introducing variability in both host and bacterial genetics, resulting in changes in vaccine-mediated protection as measured both by bacterial burden as well as histopathology. These differences can be harnessed in future studies to identify immune correlates of vaccine efficacy.
Assuntos
Mycobacterium tuberculosis , Animais , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/genética , Camundongos , Variação Genética , Feminino , Tuberculose/prevenção & controle , Tuberculose/imunologia , Tuberculose/microbiologia , Vacinas contra a Tuberculose/imunologia , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos BALB C , Interações Hospedeiro-Patógeno/imunologia , Vacina BCG/imunologia , Pulmão/microbiologia , Pulmão/patologia , Pulmão/imunologia , Modelos Animais de Doenças , Carga Bacteriana , VacinaçãoRESUMO
Co-activation signal that induces/sustains pleiotropic effector functions of antigen-specific γδ T cells remains unknown. Here, Mycobacteria tuberculosis (Mtb) tuberculin administration during tuberculosis (TB) skin test resulted in rapid expression of co-activation signal molecules CD137 and CD107a by fast-acting Vγ2Vδ2 T cells in TB-resistant subjects (Resisters), but not patients with active TB. And, anti-CD137 agonistic antibody treatment experiments showed that CD137 signaling enabled Vγ2Vδ2 T cells to produce more effector cytokines and inhibit intracellular Mtb growth in macrophages (Mɸ). Consistently, Mtb antigen (Ag) HMBPP stimulation induced sustainable high-level CD137 expression in fresh and activated Vγ2Vδ2 T cells from uninfected subjects, but not TB patients. CD137+Vγ2Vδ2 T-cell subtype predominantly displayed central memory phenotype and mounted better proliferative responses than CD137-Vγ2Vδ2 T-cells. In response to HMBPP, CD137+Vγ2Vδ2 T-cell subtype rapidly differentiated into greater numbers of pleiotropic effector cells producing anti-Mtb cytokines compared to CD137-Vγ2Vδ2 T subtype, with the non-canonical NF-κB pathway involved. CD137 expression in Vγ2Vδ2 T cells appeared to signal anti-Mtb effector functions leading to intracellular Mtb growth inhibition in Mɸ, and active TB disrupted such CD137-driven anti-Mtb effector functions. CD137+Vγ2Vδ2 T-cells subtype exhibited an epigenetic-driven high-level expression of GM-CSF and de novo production of GM-CSF critical for Vγ2Vδ2 T-cell controlling of Mtb growth in MÏ. Concurrently, exosomes produced by CD137+Vγ2Vδ2 T cells potently inhibited intracellular mycobacterial growth. Furthermore, adoptive transfer of human CD137+Vγ2Vδ2 T cells to Mtb-infected SCID mice conferred protective immunity against Mtb infection. Thus, our data suggest that CD137 expression/signaling drives pleiotropic γδ T-cell effector functions that inhibit intracellular Mtb growth.
Assuntos
Mycobacterium tuberculosis , Transdução de Sinais , Tuberculose , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Humanos , Mycobacterium tuberculosis/imunologia , Transdução de Sinais/imunologia , Tuberculose/imunologia , Tuberculose/microbiologia , Camundongos , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Feminino , Animais , Macrófagos/imunologia , Masculino , Adulto , Antígenos de Bactérias/imunologia , Citocinas/metabolismo , Citocinas/imunologia , Ativação Linfocitária/imunologia , Camundongos SCIDRESUMO
Tuberculosis (TB) is one of the infectious diseases caused by the pathogen Mycobacterium tuberculosis that continuously threatens the global human health. Bacillus Calmette-Guérin (BCG) vaccine is the only vaccine that has been used clinically to prevent tuberculosis in recent centuries, but its limitations in preventing latent infection and reactivation of tuberculosis do not provide full protection. In this study, we selected the membrane-associated antigen Rv1513 of Mycobacterium. In order to achieve stable expression and function of the target gene, the prokaryotic expression recombinant vector pET30b-Rv1513 was constructed and expressed and purified its protein. Detection of IFN- γ levels in the peripheral blood of TB patients stimulated by whole blood interferon release assay (WBIA) and multi-microsphere flow immunofluorescence luminescence (MFCIA) revealed that the induced production of cytokines, such as IFN-γ and IL-6, was significantly higher than that in the healthy group. Rv1513 combined with adjuvant DMT (adjuvant system liposomes containing dimethyldioctadecylammonium bromide (DDA), monophospholipid A (MPL), and trehalose-660-dibenzoic acid (TDB)) was used to detect serum specific antibodies, cytokine secretion from splenic suprasplenic cell supernatants, and multifunctional T-cell levels in splenocytes in immunised mice. The levels of IFN-γ, TNF-α, and IL-2 secreted by mouse splenocytes were found in the Rv1513+DMT group and the BCG+Rv1513+DMT group. The serum levels of IgG and its subclasses and the number of IFN-γ+T cells, TNF-α+T and IFN-γ+TNF-α+T cells in the induced CD4+/CD8+T cells in mice were significantly higher than those in the BCG group, and the highest levels were found in the BCG+Rv1513+DMT group. These findings suggest that Rv1513/DMT may serve as a potential subunit vaccine candidate that may be effective as a booster vaccine after the first BCG vaccination.
Assuntos
Mycobacterium tuberculosis , Células Th1 , Vacinas contra a Tuberculose , Tuberculose , Animais , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/genética , Camundongos , Humanos , Células Th1/imunologia , Vacinas contra a Tuberculose/imunologia , Vacinas contra a Tuberculose/genética , Vacinas contra a Tuberculose/administração & dosagem , Tuberculose/imunologia , Tuberculose/prevenção & controle , Tuberculose/microbiologia , Feminino , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/genética , Citocinas/metabolismo , Citocinas/imunologia , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/genética , Interferon gama/imunologia , Interferon gama/metabolismo , Camundongos Endogâmicos BALB C , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Adjuvantes Imunológicos/administração & dosagem , AdultoRESUMO
Chronic infections, including Mycobacterium tuberculosis (Mtb)-caused tuberculosis (TB), can induce host immune exhaustion. However, the key checkpoint molecules involved in this process and the underlying regulatory mechanisms remain largely undefined, which impede the application of checkpoint-based immunotherapy in infectious diseases. Here, through adopting time-of-flight mass cytometry and transcriptional profiling to systematically analyze natural killer (NK) cell surface receptors, we identify leukocyte immunoglobulin like receptor B1 (LILRB1) as a critical checkpoint receptor that defines a TB-associated cell subset (LILRB1+ NK cells) and drives NK cell exhaustion in TB. Mechanistically, Mtb-infected macrophages display high expression of human leukocyte antigen-G (HLA-G), which upregulates and activates LILRB1 on NK cells to impair their functions by inhibiting mitogen-activated protein kinase (MAPK) signaling via tyrosine phosphatases SHP1/2. Furthermore, LILRB1 blockade restores NK cell-dependent anti-Mtb immunity in immuno-humanized mice. Thus, LILRB1-HLA-G axis constitutes a NK cell immune checkpoint in TB and serves as a promising immunotherapy target.
Assuntos
Antígenos HLA-G , Células Matadoras Naturais , Receptor B1 de Leucócitos Semelhante a Imunoglobulina , Mycobacterium tuberculosis , Tuberculose , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Antígenos HLA-G/metabolismo , Antígenos HLA-G/genética , Antígenos HLA-G/imunologia , Humanos , Animais , Tuberculose/imunologia , Tuberculose/microbiologia , Camundongos , Mycobacterium tuberculosis/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Receptores Imunológicos/metabolismo , Receptores Imunológicos/genética , Antígenos CDRESUMO
Tuberculosis and AIDS remain two of the most relevant human infectious diseases. The pathogens that cause them, Mycobacterium tuberculosis (Mtb) and HIV, individually elicit an immune response that treads the line between beneficial and detrimental to the host. Co-infection further complexifies this response since the different cytokines acting on one infection might facilitate the dissemination of the other. In these responses, the role of type I interferons is often associated with antiviral mechanisms, while for bacteria such as Mtb, their importance and clinical relevance as a suitable target for manipulation are more controversial. In this article, we review the recent knowledge on how these interferons play distinct roles and sometimes have opposite consequences depending on the stage of the pathogenesis. We highlight the dichotomy between the acute and chronic infections displayed by both infections and how type I interferons contribute to an initial control of each infection individually, while their chronic induction, particularly during HIV infection, might facilitate Mtb primo-infection and progression to disease. We expect that further findings and their systematization will allow the definition of windows of opportunity for interferon manipulation according to the stage of infection, contributing to pathogen clearance and control of immunopathology.