101
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Dawa S, Menon D, Arumugam P, Bhaskar AK, Mondal M, Rao V, Gandotra S. Inhibition of Granuloma Triglyceride Synthesis Imparts Control of Mycobacterium tuberculosis Through Curtailed Inflammatory Responses. Front Immunol 2021; 12:722735. [PMID: 34603294 PMCID: PMC8479166 DOI: 10.3389/fimmu.2021.722735] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 08/25/2021] [Indexed: 12/11/2022] Open
Abstract
Lipid metabolism plays a complex and dynamic role in host-pathogen interaction during Mycobacterium tuberculosis infection. While bacterial lipid metabolism is key to the success of the pathogen, the host also offers a lipid rich environment in the form of necrotic caseous granulomas, making this association beneficial for the pathogen. Accumulation of the neutral lipid triglyceride, as lipid droplets within the cellular cuff of necrotic granulomas, is a peculiar feature of pulmonary tuberculosis. The role of triglyceride synthesis in the TB granuloma and its impact on the disease outcome has not been studied in detail. Here, we identified diacylglycerol O-acyltransferase 1 (DGAT1) to be essential for accumulation of triglyceride in necrotic TB granulomas using the C3HeB/FeJ murine model of infection. Treatment of infected mice with a pharmacological inhibitor of DGAT1 (T863) led to reduction in granuloma triglyceride levels and bacterial burden. A decrease in bacterial burden was associated with reduced neutrophil infiltration and degranulation, and a reduction in several pro-inflammatory cytokines including IL1β, TNFα, IL6, and IFNβ. Triglyceride lowering impacted eicosanoid production through both metabolic re-routing and via transcriptional control. Our data suggests that manipulation of lipid droplet homeostasis may offer a means for host directed therapy in Tuberculosis.
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Affiliation(s)
- Stanzin Dawa
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.,Cardiorespiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Dilip Menon
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.,Cardiorespiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Prabhakar Arumugam
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.,Cardiorespiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Akash Kumar Bhaskar
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.,Cardiorespiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Moumita Mondal
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.,Cardiorespiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Vivek Rao
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.,Cardiorespiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Sheetal Gandotra
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.,Cardiorespiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
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102
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Multifaceted roles of a bioengineered nanoreactor in repressing radiation-induced lung injury. Biomaterials 2021; 277:121103. [PMID: 34478930 DOI: 10.1016/j.biomaterials.2021.121103] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 08/03/2021] [Accepted: 08/26/2021] [Indexed: 12/30/2022]
Abstract
Radiation-induced lung injury (RILI) is a potentially fatal and dose-limiting complication of thoracic cancer radiotherapy. However, effective therapeutic agents for this condition are limited. Here, we describe a novel strategy to exert additive effects of a non-erythropoietic EPO derivative (ARA290), along with a free radical scavenger, superoxide dismutase (SOD), using a bioengineered nanoreactor (SOD@ARA290-HBc). ARA290-chimeric nanoreactor makes SOD present in a confined reaction space by encapsulation into its interior to heighten stability against denaturing stimuli. In a RILI mouse model, intratracheal administration of SOD@ARA290-HBc was shown to significantly ameliorate acute radiation pneumonitis and pulmonary fibrosis. Our investigations revealed that SOD@ARA290-HBc performs its radioprotective effects by protecting against radiation induced alveolar epithelial cell apoptosis and ferroptosis, suppressing oxidative stress, inhibiting inflammation and by modulating the infiltrated macrophage phenotype, or through a combination of these mechanisms. In conclusion, SOD@ARA29-HBc is a potential therapeutic agent for RILI, and given its multifaceted roles, it may be further developed as a translational nanomedicine for other related disorders.
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103
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Piergallini TJ, Scordo JM, Pino PA, Schlesinger LS, Torrelles JB, Turner J. Acute Inflammation Confers Enhanced Protection against Mycobacterium tuberculosis Infection in Mice. Microbiol Spectr 2021; 9:e0001621. [PMID: 34232086 PMCID: PMC8552513 DOI: 10.1128/spectrum.00016-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 06/02/2021] [Indexed: 01/02/2023] Open
Abstract
Inflammation plays a crucial role in the control of Mycobacterium tuberculosis infection. In this study, we demonstrate that an inflammatory pulmonary environment at the time of infection mediated by lipopolysaccharide treatment in mice confers enhanced protection against M. tuberculosis for up to 6 months postinfection. This early and transient inflammatory environment was associated with a neutrophil and CD11b+ cell influx and increased inflammatory cytokines. In vitro infection demonstrated that neutrophils from lipopolysaccharide-treated mice exhibited increased association with M. tuberculosis and had a greater innate capacity for killing M. tuberculosis. Finally, partial depletion of neutrophils in lipopolysaccharide-treated mice showed an increase in M. tuberculosis burden, suggesting neutrophils played a part in the protection observed in lipopolysaccharide-treated mice. These results indicate a positive role for an inflammatory environment in the initial stages of M. tuberculosis infection and suggest that acute inflammation at the time of M. tuberculosis infection can positively alter disease outcome. IMPORTANCE Mycobacterium tuberculosis, the causative agent of tuberculosis disease, is estimated to infect one-fourth of the world's population and is one of the leading causes of death due to an infectious disease worldwide. The high-level variability in tuberculosis disease responses in the human populace may be linked to immune processes related to inflammation. In many cases, inflammation appears to exasperate tuberculosis responses; however, some evidence suggests inflammatory processes improve control of M. tuberculosis infection. Here, we show an acute inflammatory stimulus in mice provides protection against M. tuberculosis for up to 6 months, suggesting acute inflammation can positively affect M. tuberculosis infection outcome.
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Affiliation(s)
- Tucker J. Piergallini
- Host-Pathogen Interactions Program, Texas Biomedical Research Institute, San Antonio, Texas, USA
- Biomedical Sciences Graduate Program, The Ohio State University, Columbus, Ohio, USA
| | - Julia M. Scordo
- Host-Pathogen Interactions Program, Texas Biomedical Research Institute, San Antonio, Texas, USA
- The Barshop Institute, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Paula A. Pino
- Population Health Program, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Larry S. Schlesinger
- Host-Pathogen Interactions Program, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Jordi B. Torrelles
- Population Health Program, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Joanne Turner
- Host-Pathogen Interactions Program, Texas Biomedical Research Institute, San Antonio, Texas, USA
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104
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Inherited PD-1 deficiency underlies tuberculosis and autoimmunity in a child. Nat Med 2021; 27:1646-1654. [PMID: 34183838 PMCID: PMC8446316 DOI: 10.1038/s41591-021-01388-5] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 05/06/2021] [Indexed: 02/06/2023]
Abstract
The pathophysiology of adverse events following programmed cell death protein 1 (PD-1) blockade, including tuberculosis (TB) and autoimmunity, remains poorly characterized. We studied a patient with inherited PD-1 deficiency and TB who died of pulmonary autoimmunity. The patient's leukocytes did not express PD-1 or respond to PD-1-mediated suppression. The patient's lymphocytes produced only small amounts of interferon (IFN)-γ upon mycobacterial stimuli, similarly to patients with inborn errors of IFN-γ production who are vulnerable to TB. This phenotype resulted from a combined depletion of Vδ2+ γδ T, mucosal-associated invariant T and CD56bright natural killer lymphocytes and dysfunction of other T lymphocyte subsets. Moreover, the patient displayed hepatosplenomegaly and an expansion of total, activated and RORγT+ CD4-CD8- double-negative αβ T cells, similar to patients with STAT3 gain-of-function mutations who display lymphoproliferative autoimmunity. This phenotype resulted from excessive amounts of STAT3-activating cytokines interleukin (IL)-6 and IL-23 produced by activated T lymphocytes and monocytes, and the STAT3-dependent expression of RORγT by activated T lymphocytes. Our work highlights the indispensable role of human PD-1 in governing both antimycobacterial immunity and self-tolerance, while identifying potentially actionable molecular targets for the diagnostic and therapeutic management of TB and autoimmunity in patients on PD-1 blockade.
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105
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The Immune System Throws Its Traps: Cells and Their Extracellular Traps in Disease and Protection. Cells 2021; 10:cells10081891. [PMID: 34440659 PMCID: PMC8391883 DOI: 10.3390/cells10081891] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 07/12/2021] [Accepted: 07/14/2021] [Indexed: 12/21/2022] Open
Abstract
The first formal description of the microbicidal activity of extracellular traps (ETs) containing DNA occurred in neutrophils in 2004. Since then, ETs have been identified in different populations of cells involved in both innate and adaptive immune responses. Much of the knowledge has been obtained from in vitro or ex vivo studies; however, in vivo evaluations in experimental models and human biological materials have corroborated some of the results obtained. Two types of ETs have been described—suicidal and vital ETs, with or without the death of the producer cell. The studies showed that the same cell type may have more than one ETs formation mechanism and that different cells may have similar ETs formation mechanisms. ETs can act by controlling or promoting the mechanisms involved in the development and evolution of various infectious and non-infectious diseases, such as autoimmune, cardiovascular, thrombotic, and neoplastic diseases, among others. This review discusses the presence of ETs in neutrophils, macrophages, mast cells, eosinophils, basophils, plasmacytoid dendritic cells, and recent evidence of the presence of ETs in B lymphocytes, CD4+ T lymphocytes, and CD8+ T lymphocytes. Moreover, due to recently collected information, the effect of ETs on COVID-19 is also discussed.
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106
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Park HE, Lee W, Shin MK, Shin SJ. Understanding the Reciprocal Interplay Between Antibiotics and Host Immune System: How Can We Improve the Anti-Mycobacterial Activity of Current Drugs to Better Control Tuberculosis? Front Immunol 2021; 12:703060. [PMID: 34262571 PMCID: PMC8273550 DOI: 10.3389/fimmu.2021.703060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/11/2021] [Indexed: 12/23/2022] Open
Abstract
Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb) infection, remains a global health threat despite recent advances and insights into host-pathogen interactions and the identification of diverse pathways that may be novel therapeutic targets for TB treatment. In addition, the emergence and spread of multidrug-resistant Mtb strains led to a low success rate of TB treatments. Thus, novel strategies involving the host immune system that boost the effectiveness of existing antibiotics have been recently suggested to better control TB. However, the lack of comprehensive understanding of the immunomodulatory effects of anti-TB drugs, including first-line drugs and newly introduced antibiotics, on bystander and effector immune cells curtailed the development of effective therapeutic strategies to combat Mtb infection. In this review, we focus on the influence of host immune-mediated stresses, such as lysosomal activation, metabolic changes, oxidative stress, mitochondrial damage, and immune mediators, on the activities of anti-TB drugs. In addition, we discuss how anti-TB drugs facilitate the generation of Mtb populations that are resistant to host immune response or disrupt host immunity. Thus, further understanding the interplay between anti-TB drugs and host immune responses may enhance effective host antimicrobial activities and prevent Mtb tolerance to antibiotic and immune attacks. Finally, this review highlights novel adjunctive therapeutic approaches against Mtb infection for better disease outcomes, shorter treatment duration, and improved treatment efficacy based on reciprocal interactions between current TB antibiotics and host immune cells.
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Affiliation(s)
- Hyun-Eui Park
- Department of Microbiology and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, South Korea
| | - Wonsik Lee
- School of Pharmacy, Sungkyunkwan University, Suwon, South Korea
| | - Min-Kyoung Shin
- Department of Microbiology and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, South Korea
| | - Sung Jae Shin
- Department of Microbiology, Institute for Immunology and Immunological Diseases, Brain Korea 21 Project for Graduate School of Medical Science, Yonsei University College of Medicine, Seoul, South Korea
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107
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Feng J, Bian Q, He X, Zhang H, He J. A LncRNA-miRNA-mRNA ceRNA regulatory network based tuberculosis prediction model. Microb Pathog 2021; 158:105069. [PMID: 34175436 DOI: 10.1016/j.micpath.2021.105069] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/14/2021] [Accepted: 06/21/2021] [Indexed: 12/16/2022]
Abstract
The high incidence of tuberculosis (TB) has brought serious social burdens and it is urgent to explore the mechanism of TB development. This study was conducted to analyze the role of lncRNA-miRNA-mRNA regulatory network and its contained nodes involved in TB to identify crucial biomarkers for early diagnosis of TB. Long-noncoding RNAs (lncRNAs), messenger RNA (mRNAs) and microRNAs (miRNAs) expression profiles of TB patients and healthy individuals were downloaded from the GSE34608 dataset. Weighted gene co-expression network analysis (WGCNA) was performed to identified the key modules related to TB and the highly related mRNA-lncRNA pair in the module. Based on highly related mRNAs and lncRNAs in greenyellow module, lncRNA-miRNA-mRNA competing endogenous RNA (ceRNA) network was constructed. The DE-mRNAs in the network were functionally enriched with Gene ontology (GO) and Gene set enrichment analysis (GSEA). Least absolute shrinkage and selection operator (LASSO) algorithm and receiver operating characteristic curve (ROC) were used to construct and evaluate the prediction model of TB. We identified 3267 DE-mRNAs, 484 DE-lncRNAs and 69 DE-miRNAs between the TB and healthy subjects, from which 8 DE-mRNAs, 14 DE-lncRNAs and 3 DE-miRNAs were used to construct the ceRNA network. The genes contained in the ceRNA network were mainly enriched in neutrophil mediated immune response, including neutrophil activation, degradation and signal transduction. ROC analysis revealed that has-miR-140-5p, has-miR-142-3p and the LASSO cox prediction model based on HMGA1 and CAPN1 have potential value for forecasting TB (AUC > 0.7). Hence, our study provides a new perspective from the lncRNA-miRNA-mRNA ceRNA regulatory network for TB diagnosis and treatment.
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Affiliation(s)
- Jinfang Feng
- Clinical Laboratory Department, Guangyuan Central Hospital, Guangyuan, 628000, China
| | - Qin Bian
- Clinical Laboratory Department, Guangyuan Central Hospital, Guangyuan, 628000, China.
| | - Xianwei He
- Clinical Laboratory Department, Guangyuan Central Hospital, Guangyuan, 628000, China
| | - Han Zhang
- Clinical Laboratory Department, Guangyuan Central Hospital, Guangyuan, 628000, China
| | - Jiujiang He
- Clinical Laboratory Department, Guangyuan Central Hospital, Guangyuan, 628000, China
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108
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Dual mTORC1/mTORC2 Inhibition as a Host-Directed Therapeutic Target in Pathologically Distinct Mouse Models of Tuberculosis. Antimicrob Agents Chemother 2021; 65:e0025321. [PMID: 33903099 PMCID: PMC8373221 DOI: 10.1128/aac.00253-21] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Efforts to develop more effective and shorter-course therapies for tuberculosis have included a focus on host-directed therapy (HDT). The goal of HDT is to modulate the host response to infection, thereby improving immune defenses to reduce the duration of antibacterial therapy and/or the amount of lung damage. As a mediator of innate and adaptive immune responses involved in eliminating intracellular pathogens, autophagy is a potential target for HDT in tuberculosis. Because Mycobacterium tuberculosis modulates mammalian target of rapamycin (mTOR) signaling to impede autophagy, pharmacologic mTOR inhibition could provide effective HDT. mTOR exists within two distinct multiprotein complexes, mTOR complex-1 (mTORC1) and mTOR complex-2 (mTORC2). Rapamycin and its analogs only partially inhibit mTORC1. We hypothesized that novel mTOR kinase inhibitors blocking both complexes would have expanded therapeutic potential. We compared the effects of two mTOR inhibitors, rapamycin and the orally available mTOR kinase domain inhibitor CC214-2, which blocks both mTORC1 and mTORC2, as adjunctive therapies against murine TB when added to the first-line regimen (isoniazid, rifampin, pyrazinamide, and ethambutol [RHZE]) or the novel bedaquiline-pretomanid-linezolid (BPaL) regimen. Neither mTOR inhibitor affected lung CFU counts after 4 to 8 weeks of treatment when combined with BPaL or RHZE. However, addition of CC214-2 to BPaL and RHZE was associated with significantly fewer relapses in C3HeB/FeJ mice compared to addition of rapamycin and, in RHZE-treated mice, resulted in fewer relapses than RHZE alone. Therefore, CC214-2 and related mTOR kinase inhibitors may be more effective candidates for HDT than rapamycin analogs and may have the potential to shorten the duration of TB treatment.
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109
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mSphere of Influence: the Key Role of Neutrophils in Tuberculosis and Type 2 Diabetes Comorbidity. mSphere 2021; 6:e0025121. [PMID: 34047649 PMCID: PMC8265639 DOI: 10.1128/msphere.00251-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Annie Mayer Bridwell works in the field of tuberculosis pathogenesis from the host perspective. She is fascinated by comorbidities, and in this paper, she reflects on three publications that shaped her model of neutrophil-centric pathology in tuberculosis and type 2 diabetes comorbidity. She explains that “Systems immunology of diabetes-tuberculosis comorbidity reveals signatures of disease complications” (C. A. Prada-Medina, K. F. Fukutani, N. Pavan Kumar, L. Gil-Santana, et al., Sci Rep 7:1999, 2017, https://doi.org/10.1038/s41598-017-01767-4) led her to consider neutrophils as a central immunological player in comorbid patients. “Type I IFN exacerbates disease in tuberculosis-susceptible mice by inducing neutrophil-mediated lung inflammation and NETosis” (L. Moreira-Teixeira, P. J. Stimpson, E. Stavropoulos, S. Hadebe, et al., Nat Commun 11:5566, 2020, https://doi.org/10.1038/s41467-020-19412-6) and “Diabetes primes neutrophils to undergo NETosis, which impairs wound healing” (S. L. Wong, M. Demers, K. Martinod, M. Gallant, et al., Nat Med 21:815–819, 2015, https://doi.org/10.1038/nm.3887) then shed light on neutrophil extracellular trap (NET) formation as a common pathological feature of dysregulated neutrophils in tuberculosis and diabetes, respectively. Together, these works laid the foundation for Dr. Mayer Bridwell's interest in metabolic regulation of NETosis during TB infection and diabetes comorbidity.
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110
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Simeone R, Sayes F, Lawarée E, Brosch R. Breaching the phagosome, the case of the tuberculosis agent. Cell Microbiol 2021; 23:e13344. [PMID: 33860624 DOI: 10.1111/cmi.13344] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 03/23/2021] [Accepted: 03/25/2021] [Indexed: 12/14/2022]
Abstract
The interactions between microbes and their hosts are among the most complex biological phenomena known today. The interaction may reach from overall beneficial interaction, as observed for most microbiome/microbiota related interactions to interaction with virulent pathogens, against which host cells have evolved sophisticated defence strategies. Among the latter, the confinement of invading pathogens in a phagosome plays a key role, which often results in the destruction of the invader, whereas some pathogens may counteract phagosomal arrest and survive by gaining access to the cytosol of the host cell. In the current review, we will discuss recent insights into this dynamic process of host-pathogen interaction, using Mycobacterium tuberculosis and related pathogenic mycobacteria as main examples.
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Affiliation(s)
- Roxane Simeone
- Unit for Integrated Mycobacterial Pathogenomics, Institut Pasteur, CNRS UMR 3525, Paris, France
| | - Fadel Sayes
- Unit for Integrated Mycobacterial Pathogenomics, Institut Pasteur, CNRS UMR 3525, Paris, France
| | - Emeline Lawarée
- Unit for Integrated Mycobacterial Pathogenomics, Institut Pasteur, CNRS UMR 3525, Paris, France
| | - Roland Brosch
- Unit for Integrated Mycobacterial Pathogenomics, Institut Pasteur, CNRS UMR 3525, Paris, France
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111
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Neutrophils in Tuberculosis: Cell Biology, Cellular Networking and Multitasking in Host Defense. Int J Mol Sci 2021; 22:ijms22094801. [PMID: 33946542 PMCID: PMC8125784 DOI: 10.3390/ijms22094801] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/28/2021] [Accepted: 04/28/2021] [Indexed: 12/20/2022] Open
Abstract
Neutrophils readily infiltrate infection foci, phagocytose and usually destroy microbes. In tuberculosis (TB), a chronic pulmonary infection caused by Mycobacterium tuberculosis (Mtb), neutrophils harbor bacilli, are abundant in tissue lesions, and their abundances in blood correlate with poor disease outcomes in patients. The biology of these innate immune cells in TB is complex. Neutrophils have been assigned host-beneficial as well as deleterious roles. The short lifespan of neutrophils purified from blood poses challenges to cell biology studies, leaving intracellular biological processes and the precise consequences of Mtb–neutrophil interactions ill-defined. The phenotypic heterogeneity of neutrophils, and their propensity to engage in cellular cross-talk and to exert various functions during homeostasis and disease, have recently been reported, and such observations are newly emerging in TB. Here, we review the interactions of neutrophils with Mtb, including subcellular events and cell fate upon infection, and summarize the cross-talks between neutrophils and lung-residing and -recruited cells. We highlight the roles of neutrophils in TB pathophysiology, discussing recent findings from distinct models of pulmonary TB, and emphasize technical advances that could facilitate the discovery of novel neutrophil-related disease mechanisms and enrich our knowledge of TB pathogenesis.
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