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2.
BMC Pulm Med ; 22(1): 57, 2022 Feb 09.
Article in English | MEDLINE | ID: mdl-35139852

ABSTRACT

BACKGROUND: Extracellular vesicles (EVs) play a key role in cell communication and the pathogenesis of some diseases. EVs may accelerate cell death during the course of mycobacterial infection and are also considered as a new vaccine design, drug delivery, and biomarker candidates. The current study evaluates the effects of EVs from serum samples of mycobacteria-infected patients on THP-1 monocytes and PBMC cells. METHOD: EVs were purified from the serum, then cultured separately with THP-1 monocytes and PBMCs. The cell death was determined through annexin V-FITC and PI staining. GW4869, an EVs inhibitor, was used to determine if EVs released from serum could increase THP-1 monocytes cell death. RESULTS: The cell death was significantly increased in the presence of 10 µg/ml and 5 µg/ml concentrations of the purified EVs (p < 0.05). Minimal cell death was determined in 2.5 µg/ml and 1.2 µg/ml (p < 0.05). Up to 85% of the cells were viable in the presence of the GW4869 inhibitor (p < 0.05). CONCLUSION: Direct infection of the cells with EVs released from mycobacteria-infected patients samples, the multiplicity of infection with the EVs, and virulent or avirulent mycobacteria may change the status of the cell death. The isolated EVs  from serum samples of patients with mycobacterial  infection accelerated cell death, which means that they might   not be considered as an optimal tool for developing drug delivery and vaccine against tuberculosis.


Subject(s)
Cell Death , Extracellular Vesicles/metabolism , Mycobacterium Infections/immunology , Mycobacterium/physiology , Adult , Aged, 80 and over , Female , Humans , Leukocytes, Mononuclear , Male , Middle Aged , Mycobacterium/immunology , Mycobacterium Infections/metabolism , Mycobacterium Infections/microbiology , THP-1 Cells , Virulence
3.
Tuberculosis (Edinb) ; 132: 102165, 2022 01.
Article in English | MEDLINE | ID: mdl-35045376

ABSTRACT

Mycobacterium tuberculosis (MTB) and M. avium-intracellulare complex (MAC) enter host phagocytes, such as neutrophils through lipoarabinomannan (LAM) binding to pattern-recognition receptors, inducing innate immune responses including phagocytosis. Phagocytosis of mycobacteria by human neutrophils depends on the binding of α(1 â†’ 2)-monomannose branching α(1 â†’ 6)-mannan core of LAM/lipomannan (LM), a common component among mycobacterial species, to lactosylceramide (LacCer)-enriched lipid microdomains. We investigated the binding specificities of several anti-LAM antibodies (Abs) to LAMs/LM and found anti-LAM monoclonal IgMs TMDU3 and LA066 were directed against mannan core. Each IgM showed different binding specificity to mannan core. Confocal and stimulated emission depletion microscopy revealed TMDU3 and LA066 strongly bind to MTB and MAC, respectively. Flow cytometric analysis revealed human neutrophils do not express Dectin-2, DC-SIGN or mannose receptor. Furthermore, neutrophil phagocytosis of mycobacteria was markedly inhibited by TMDU3 and LA066, respectively. Similarly, treatment of each mAb with neutrophils reduced the numbers of intracellular MAC. Together, our results suggest that the interaction of LacCer-enriched lipid microdomains with mannan core and its blocking are therapeutic or diagnostic targets for both TB and non-tuberculous mycobacteria infection.


Subject(s)
Lipopolysaccharides/immunology , Mannans/metabolism , Mycobacterium/metabolism , Neutrophils/immunology , Phagocytosis/immunology , Adult , Humans , Lipopolysaccharides/analysis , Male , Middle Aged , Mycobacterium/immunology , Neutrophils/metabolism , Phagocytosis/genetics
4.
PLoS Negl Trop Dis ; 15(12): e0010018, 2021 12.
Article in English | MEDLINE | ID: mdl-34914694

ABSTRACT

T cell receptors (TCRs) encode the history of antigenic challenge within an individual and have the potential to serve as molecular markers of infection. In addition to peptide antigens bound to highly polymorphic MHC molecules, T cells have also evolved to recognize bacterial lipids when bound to non-polymorphic CD1 molecules. One such subset, germline-encoded, mycolyl lipid-reactive (GEM) T cells, recognizes mycobacterial cell wall lipids and expresses a conserved TCR-ɑ chain that is shared among genetically unrelated individuals. We developed a quantitative PCR assay to determine expression of the GEM TCR-ɑ nucleotide sequence in human tissues and blood. This assay was validated on plasmids and T cell lines. We tested blood samples from South African subjects with or without tuberculin reactivity or with active tuberculosis disease. We were able to detect GEM TCR-ɑ above the limit of detection in 92% of donors but found no difference in GEM TCR-ɑ expression among the three groups after normalizing for total TCR-ɑ expression. In a cohort of leprosy patients from Nepal, we successfully detected GEM TCR-ɑ in 100% of skin biopsies with histologically confirmed tuberculoid and lepromatous leprosy. Thus, GEM T cells constitute part of the T cell repertoire in the skin. However, GEM TCR-ɑ expression was not different between leprosy patients and control subjects after normalization. Further, these results reveal the feasibility of developing a simple, field deployable molecular diagnostic based on mycobacterial lipid antigen-specific TCR sequences that are readily detectable in human tissues and blood independent of genetic background.


Subject(s)
Leprosy/diagnosis , Lipids/immunology , Molecular Diagnostic Techniques/methods , Mycobacterium/immunology , Receptors, Antigen, T-Cell, alpha-beta/immunology , Tuberculosis/diagnosis , Antigens, CD1/genetics , Antigens, CD1/immunology , Cell Wall/genetics , Cell Wall/immunology , Cohort Studies , Humans , Leprosy/blood , Leprosy/immunology , Leprosy/microbiology , Mycobacterium/genetics , Mycobacterium/isolation & purification , Nepal , Polymerase Chain Reaction , Receptors, Antigen, T-Cell, alpha-beta/blood , Receptors, Antigen, T-Cell, alpha-beta/genetics , South Africa , T-Lymphocytes/immunology , T-Lymphocytes/microbiology , Tuberculosis/blood , Tuberculosis/immunology , Tuberculosis/microbiology
5.
Front Immunol ; 12: 747387, 2021.
Article in English | MEDLINE | ID: mdl-34630426

ABSTRACT

Mycobacterial diseases are a major public health challenge. Their causative agents include, in order of impact, members of the Mycobacterium tuberculosis complex (causing tuberculosis), Mycobacterium leprae (causing leprosy), and non-tuberculous mycobacterial pathogens including Mycobacterium ulcerans. Macrophages are mycobacterial targets and they play an essential role in the host immune response to mycobacteria. This review aims to provide a comprehensive understanding of the immune-metabolic adaptations of the macrophage to mycobacterial infections. This metabolic rewiring involves changes in glycolysis and oxidative metabolism, as well as in the use of fatty acids and that of metals such as iron, zinc and copper. The macrophage metabolic adaptations result in changes in intracellular metabolites, which can post-translationally modify proteins including histones, with potential for shaping the epigenetic landscape. This review will also cover how critical tuberculosis co-morbidities such as smoking, diabetes and HIV infection shape host metabolic responses and impact disease outcome. Finally, we will explore how the immune-metabolic knowledge gained in the last decades can be harnessed towards the design of novel diagnostic and therapeutic tools, as well as vaccines.


Subject(s)
Adaptation, Physiological/immunology , Host-Pathogen Interactions/immunology , Macrophages/immunology , Mycobacterium Infections/immunology , Animals , Humans , Macrophages/metabolism , Mycobacterium/immunology , Mycobacterium Infections/metabolism
6.
Article in English | MEDLINE | ID: mdl-34379957

ABSTRACT

BACKGROUND: Contacts of leprosy patients have an increased risk of infection with Mycobacterium leprae. Contact tracing and chemo- or immunoprophylaxis are important means of preventing leprosy transmission. AIMS: We aimed to evaluate the efficacy of immunoprophylaxis with Mycobacterium indicus pranii vaccine in reducing anti-phenolic glycolipid-1 titers in household contacts of leprosy patients. METHODS: This prospective single-center study was conducted in a tertiary care center in North India from January 2015 to December 2016. Contacts of leprosy patients (both paucibacillary and multibacillary) were screened for anti-phenolic glycolipid-1 antibodies with enzyme-linked immunosorbent assay. Those found positive were given immunoprophylaxis with a single dose of Mycobacterium indicus pranii vaccine, and anti-phenolic glycolipid-1 titers were evaluated at six and 12 months. All contacts were clinically followed for three years. RESULTS: Of the 135 contacts of 98 leprosy patients that were screened, 128 were recruited. Seventeen of these contacts were positive for anti-phenolic glycolipid-1 antibodies and were given Mycobacterium indicus pranii vaccine. Two contacts were lost to follow-up. After immunoprophylaxis, anti-phenolic glycolipid-1 titers were negative in all patients at all intervals, and no contact developed any clinical signs or symptoms of leprosy during the three-year follow-up. LIMITATIONS: The small number of contacts studied, the short follow-up period and the absence of a control group were limitations of this study. Dicussion: We could not find any papers on natural decline of PGL 1 titres in contacts, although in leprosy patients, these titres may even increase after completion of treatment. However the titres do correlate with bacterial load (reference: Int J Lepr Other Mycobact Dis. 1998 Sep;66(3):356-64) so if the tires decrease or become negative it may be considered as an indirect evidence of bacillary clearance. Hence we may suggest the protective efficacy. Furthermore, as the editor mentioned, considering the small number of positive patients, a control group was not possible in the present pilot study, but such studies may be carried out in the future. CONCLUSION: Immunoprophylaxis with Mycobacterium indicus pranii vaccine is effective and safe in preventing disease in contacts of leprosy patients. However, these findings need to be replicated in larger studies.


Subject(s)
Antibodies, Bacterial/blood , Bacterial Vaccines , Glycolipids/immunology , Leprosy/immunology , Mycobacterium/immunology , Adult , Contact Tracing , Female , Humans , Leprosy/transmission , Male , Pilot Projects , Prospective Studies , Tertiary Care Centers
7.
Int J Mol Sci ; 22(16)2021 Aug 12.
Article in English | MEDLINE | ID: mdl-34445367

ABSTRACT

Rheumatoid arthritis (RA) is a chronic multisystem disease, therapy of which remains a challenge for basic research. The present work examined the effect of unconjugated bilirubin (UCB) administration in adjuvant-induced arthritis (AIA)-an experimental model, in which oxidative stress (OS), inflammation and inadequate immune response are often similar to RA. Male Lewis rats were randomized into groups: CO-control, AIA-untreated adjuvant-induced arthritis, AIA-BIL-adjuvant-induced arthritis administrated UCB, CO-BIL-control with administrated UCB. UCB was administered intraperitoneally 200 mg/kg of body weight daily from 14th day of the experiment, when clinical signs of the disease are fully manifested, to 28th day, the end of the experiment. AIA was induced by a single intradermal immunization at the base of the tail with suspension of Mycobacterium butyricum in incomplete Freund's adjuvant. Clinical, hematologic, biochemical and histologic examinations were performed. UCB administration to animals with AIA lead to a significant decrease in hind paws volume, plasma levels of C-reactive protein (CRP) and ceruloplasmin, drop of leukocytes, lymphocytes, erythrocytes, hemoglobin and an increase in platelet count. UCB administration caused significantly lowered oxidative damage to DNA in arthritic animals, whereas in healthy controls it induced considerable oxidative damage to DNA. UCB administration also induced atrophy of the spleen and thymus in AIA and CO animals comparing to untreated animals. Histological signs of joint damage assessed by neutrophils infiltration and deposition of fibrin were significantly reduced by UCB administration. The effects of exogenously administered UCB to the animals with adjuvant-induced arthritis might be identified as therapeutic, in contrast to the effects of UCB administration in healthy animals rather classified as toxic.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Arthritis, Experimental/drug therapy , Bilirubin/administration & dosage , Freund's Adjuvant/adverse effects , Lipids/adverse effects , Mycobacterium/immunology , Animals , Anti-Inflammatory Agents/pharmacology , Arthritis, Experimental/chemically induced , Arthritis, Experimental/metabolism , Bilirubin/pharmacology , C-Reactive Protein , Ceruloplasmin/metabolism , Injections, Intraperitoneal , Male , Oxidative Stress/drug effects , Peptide Fragments/blood , Random Allocation , Rats , Rats, Inbred Lew , Treatment Outcome
9.
Curr Opin Immunol ; 72: 262-271, 2021 10.
Article in English | MEDLINE | ID: mdl-34315005

ABSTRACT

Clinical disease caused by the agent of tuberculosis, Mycobacterium tuberculosis, and by less virulent mycobacteria, such as bacillus Calmette-Guérin (BCG) vaccines and environmental mycobacteria, can result from inborn errors of immunity (IEIs). IEIs underlie more than 450 conditions, each associated with an impairment of the development and/or function of hematopoietic and/or non-hematopoietic cells involved in host defense. Only a minority of IEIs confer predisposition to mycobacterial disease. The IEIs underlying susceptibility to bona fide tuberculosis are less well delineated than those responsible for susceptibility to less virulent mycobacteria. However, all these IEIs share a defining feature: the impairment of immunity mediated by interferon gamma (IFN-γ). More profound IFN-γ deficiency is associated with a greater vulnerability to weakly virulent mycobacteria, whereas more selective IFN-γ deficiency is associated with a more selective predisposition to mycobacterial disease. We review here recent progress in the study of IEIs underlying mycobacterial diseases.


Subject(s)
Genetic Predisposition to Disease , Genetic Variation , Immunity/genetics , Mycobacterium Infections/etiology , Mycobacterium , Alleles , Autoimmunity , GATA2 Deficiency/complications , Humans , Immune System Diseases/complications , Immune System Diseases/diagnosis , Immune System Diseases/genetics , Interferon-gamma/immunology , Mutation , Mycobacterium/immunology , Mycobacterium tuberculosis/immunology , Organ Specificity/genetics , Organ Specificity/immunology , Phenotype , Severe Combined Immunodeficiency/complications , Severe Combined Immunodeficiency/diagnosis , Severe Combined Immunodeficiency/genetics
10.
Int J Mol Sci ; 22(14)2021 Jul 15.
Article in English | MEDLINE | ID: mdl-34299217

ABSTRACT

The mycobacterial cell wall is composed of large amounts of lipids with varying moieties. Some mycobacteria species hijack host cells and promote lipid droplet accumulation to build the cellular environment essential for their intracellular survival. Thus, lipids are thought to be important for mycobacteria survival as well as for the invasion, parasitization, and proliferation within host cells. However, their physiological roles have not been fully elucidated. Recent studies have revealed that mycobacteria modulate the peroxisome proliferator-activated receptor (PPAR) signaling and utilize host-derived triacylglycerol (TAG) and cholesterol as both nutrient sources and evasion from the host immune system. In this review, we discuss recent findings that describe the activation of PPARs by mycobacterial infections and their role in determining the fate of bacilli by inducing lipid metabolism, anti-inflammatory function, and autophagy.


Subject(s)
Mycobacterium Infections/microbiology , Mycobacterium/metabolism , Peroxisome Proliferator-Activated Receptors/metabolism , Animals , Autophagy/physiology , Cholesterol/metabolism , Humans , Lipid Metabolism , Mycobacterium/growth & development , Mycobacterium/immunology , Mycobacterium Infections/immunology , Mycobacterium Infections/metabolism , Peroxisome Proliferator-Activated Receptors/genetics , Signal Transduction
11.
Iran J Allergy Asthma Immunol ; 20(3): 376-381, 2021 Jun 06.
Article in English | MEDLINE | ID: mdl-34134458

ABSTRACT

Mendelian susceptibility to mycobacterial disease (MSMD) is a rare group of genetic disorders characterized by infections with weakly virulent environmental mycobacteria (EM) or Mycobacterium bovis bacillus Calmette-Guérin (BCG). Herein, we described the case of a 4.5-year-old boy with protein-losing enteropathy, lymphoproliferation, and candidiasis, who was found to have disseminated Mycobacterium simiae infection. A homozygous mutation in the IL12B gene, c.527_528delCT (p.S176Cfs*12) was identified, responsible for the complete IL-12p40 deficiency. He was resistant to anti-mycobacterial treatment and finally died due to sepsis-related complications.


Subject(s)
Immunocompromised Host , Interleukin-12 Subunit p40/deficiency , Mycobacterium Infections/microbiology , Mycobacterium/pathogenicity , Primary Immunodeficiency Diseases/immunology , Anti-Bacterial Agents/therapeutic use , Child, Preschool , Drug Resistance, Bacterial , Fatal Outcome , Genetic Predisposition to Disease , Homozygote , Host-Pathogen Interactions , Humans , Interleukin-12 Subunit p40/genetics , Male , Mutation , Mycobacterium/immunology , Mycobacterium Infections/diagnosis , Mycobacterium Infections/drug therapy , Mycobacterium Infections/immunology , Phenotype , Primary Immunodeficiency Diseases/diagnosis , Primary Immunodeficiency Diseases/genetics , Sepsis/immunology , Sepsis/microbiology , Treatment Outcome
12.
Front Immunol ; 12: 632304, 2021.
Article in English | MEDLINE | ID: mdl-33953709

ABSTRACT

Cross-reactive vaccines recognize common molecular patterns in pathogens and are able to confer broad spectrum protection against different infections. Antigens common to pathogenic bacteria that induce broad immune responses, such as the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of the genera Listeria, Mycobacterium, or Streptococcus, whose sequences present more than 95% homology at the N-terminal GAPDH1-22 peptide, are putative candidates for universal vaccines. Here, we explore vaccine formulations based on dendritic cells (DC) loaded with two molecular forms of Listeria monocytogenes GAPDH (LM-GAPDH), such as mRNA carriers or recombinant proteins, and compare them with the same molecular forms of three other antigens used in experimental vaccines, listeriolysin O of Listeria monocytogeness, Ag85A of Mycobacterium marinum, and pneumolysin of Streptococcus pneumoniae. DC loaded with LM-GAPDH recombinant proteins proved to be the safest and most immunogenic vaccine vectors, followed by mRNA encoding LM-GAPDH conjugated to lipid carriers. In addition, macrophages lacked sufficient safety as vaccines for all LM-GAPDH molecular forms. The ability of DC loaded with LM-GAPDH recombinant proteins to induce non-specific DC activation explains their adjuvant potency and their capacity to trigger strong CD4+ and CD8+ T cell responses explains their high immunogenicity. Moreover, their capacity to confer protection in vaccinated mice against challenges with L. monocytogenes, M. marinum, or S. pneumoniae validated their efficiency as cross-reactive vaccines. Cross-protection appears to involve the induction of high percentages of GAPDH1-22 specific CD4+ and CD8+ T cells stained for intracellular IFN-γ, and significant levels of peptide-specific antibodies in vaccinated mice. We concluded that DC vaccines loaded with L. monocytogenes GAPDH recombinant proteins are cross-reactive vaccines that seem to be valuable tools in adult vaccination against Listeria, Mycobacterium, and Streptococcus taxonomic groups.


Subject(s)
Bacterial Vaccines/immunology , Glyceraldehyde-3-Phosphate Dehydrogenases/immunology , Lipids/immunology , Listeria/immunology , Mycobacterium/immunology , RNA, Messenger/immunology , Streptococcus/immunology , Adjuvants, Immunologic , Animals , Antibodies, Bacterial/blood , Antigens, Bacterial/genetics , Antigens, Bacterial/immunology , Bacterial Infections/prevention & control , Bacterial Vaccines/administration & dosage , Bacterial Vaccines/genetics , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Cross Protection , Cross Reactions , Dendritic Cells/immunology , Glyceraldehyde-3-Phosphate Dehydrogenases/genetics , Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , Interferon-gamma/immunology , Lipids/chemistry , Listeria/enzymology , Listeria/genetics , Mice , RNA, Messenger/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/immunology
13.
mSphere ; 6(3)2021 05 05.
Article in English | MEDLINE | ID: mdl-33952660

ABSTRACT

Mycobacterium tuberculosis infections claim more than a million lives each year, and better treatments or vaccines are required. A crucial pathogenicity factor is translocation from phagolysosomes to the cytosol upon phagocytosis by macrophages. Translocation from the phagolysosome to the cytosol is an ESX-1-dependent process, as previously shown in vitro Here, we show that in vivo, mycobacteria also translocate to the cytosol but mainly when host immunity is compromised. We observed only low numbers of cytosolic bacilli in mice, armadillos, zebrafish, and patient material infected with M. tuberculosis, M. marinum, or M. leprae In contrast, when innate or adaptive immunity was compromised, as in severe combined immunodeficiency (SCID) or interleukin-1 receptor 1 (IL-1R1)-deficient mice, significant numbers of cytosolic M. tuberculosis bacilli were detected in the lungs of infected mice. Taken together, in vivo, translocation to the cytosol of M. tuberculosis is controlled by adaptive immune responses as well as IL-1R1-mediated signals.IMPORTANCE For decades, Mycobacterium tuberculosis has been one of the deadliest pathogens known. Despite infecting approximately one-third of the human population, no effective treatment or vaccine is available. A crucial pathogenicity factor is subcellular localization, as M. tuberculosis can translocate from phagolysosome to the cytosol in macrophages. The situation in vivo is more complicated. In this study, we establish that high-level cytosolic escape of mycobacteria can indeed occur in vivo but mainly when host resistance is compromised. The IL-1 pathway is crucial for the control of the number of cytosolic mycobacteria. The establishment that immune signals result in the clearance of cells containing cytosolic mycobacteria connects two important fields, cell biology and immunology, which is vital for the understanding of the pathology of M. tuberculosis.


Subject(s)
Cytosol/microbiology , Mycobacterium/immunology , Mycobacterium/pathogenicity , Phagosomes/microbiology , Receptors, Interleukin-1/genetics , Receptors, Interleukin-1/immunology , Signal Transduction/immunology , Animals , Armadillos/microbiology , Bacterial Translocation , Cytosol/immunology , Female , Humans , Leprosy/microbiology , Male , Mice , Mice, Inbred BALB C , Mice, SCID , Mycobacterium/classification , Phagosomes/immunology , Skin/microbiology , Skin/pathology , THP-1 Cells , Zebrafish
14.
Front Immunol ; 12: 662128, 2021.
Article in English | MEDLINE | ID: mdl-34012446

ABSTRACT

NK cells play an important role in the control of tuberculosis infection: they are not only able to kill the infected cells, but also control the activity of macrophages and development of the adaptive immune response. Still, there is little information on the role of specific NK cell subsets in this network. In this study, we focused on the mycobacteria-driven responses of the NK cells expressing HLA-DR - a type of MHC class II. We have revealed that this subset is increased in the peripheral blood of patients with primary diagnosed tuberculosis, and expands in response to in vitro stimulation with ultrasonically destroyed Mycobacterium tuberculosis cells (sonicate). The expanded HLA-DR+ NK cells had less differentiated phenotype, higher proliferative activity and increased expression of NKp30 and NKp46 receptors. HLA-DR+CD56dim NK cells showed higher IFNγ production and degranulation level than the respective HLA-DR- NK cells in response to both 24 h and 7 day stimulation with sonicate, while HLA-DR+CD56bright NK cells mostly demonstarted similar high responsiveness to the same stimulating conditions as their HLA-DR-CD56bright counterparts. After preliminary incubation with destroyed mycobacteria, cytokine-activated HLA-DR-expressing NK cells were able to mediate mycobacteria-induced and HLA-DR-dependent cytokine production in autologous CD4+ T cells. Thus, functionally active HLA-DR+ cells seem to be one of the NK cell subsets providing an important link to the adaptive immunity.


Subject(s)
Antigens, Bacterial/immunology , HLA-DR Antigens/immunology , Killer Cells, Natural/immunology , Lymphocyte Activation/immunology , Mycobacterium/immunology , T-Lymphocytes/immunology , Adaptive Immunity , Antigens, Bacterial/pharmacology , HLA-DR Antigens/genetics , Humans , Interferon-gamma/immunology , Killer Cells, Natural/drug effects , Lymphocyte Activation/drug effects , Mycobacterium/chemistry , Phenotype , T-Lymphocytes/drug effects
15.
Vet Immunol Immunopathol ; 237: 110268, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34023615

ABSTRACT

In the present study, calves were infected with Mycobacterium avium subsp. paratuberculosis (MAP), Mycobacterium avium subsp. avium (M. avium), Mycobacterium kansasii (M. kansasii), or Mycobacterium bovis (M. bovis) to determine differences in cellular immunity. Comparative cellular responses were assessed upon stimulation of cells with mycobacterial whole cell sonicates respective of each infection group. Antigen-specific whole blood interferon gamma (IFN-γ) responses were observed in all infection groups compared to noninfected control calves, however, responses were more robust for M. bovis calves. Upon antigen stimulation of PBMCs, secretion of IFN-γ and IL-10 was higher for M. bovis calves compared to other infection groups. In contrast, IL-12 secretion was lower for M. bovis calves compared to MAP infected calves. Within the total PBMC population, higher numbers of CD4+, CD8+, and γδ TCR + T cells were observed for MAP and M. avium calves compared to M. bovis calves. This aligned with higher expression of CD26 on these subpopulations for MAP and M. avium calves, as well. In contrast, greater expression of CD25 was observed on CD4+ and γδ TCR + T cells and natural killer cells for M. bovis calves. Overall, similarities in cellular immune responses were observed between the closely related MAP and M. avium during infection of calves. In contrast, significant differences were noted between calves infected with MAP and M. bovis. This suggests that host immune responses to different mycobacteria may impact interpretation of diagnostic tools based upon their cellular immunity.


Subject(s)
Cattle Diseases/microbiology , Immunity, Cellular , Mycobacterium Infections/veterinary , Animals , Cattle , Cattle Diseases/immunology , Cross Reactions , Cytokines/immunology , Flow Cytometry/veterinary , Interferon-gamma/immunology , Lymphocyte Subsets/immunology , Male , Mycobacterium/immunology , Mycobacterium Infections/immunology , Mycobacterium Infections/microbiology , Mycobacterium avium subsp. paratuberculosis/immunology , Mycobacterium bovis/immunology , Mycobacterium kansasii/immunology , Species Specificity
16.
Nat Commun ; 12(1): 2027, 2021 04 01.
Article in English | MEDLINE | ID: mdl-33795674

ABSTRACT

The immune response to mycobacteria is characterized by granuloma formation, which features multinucleated giant cells as a unique macrophage type. We previously found that multinucleated giant cells result from Toll-like receptor-induced DNA damage and cell autonomous cell cycle modifications. However, the giant cell progenitor identity remained unclear. Here, we show that the giant cell-forming potential is a particular trait of monocyte progenitors. Common monocyte progenitors potently produce cytokines in response to mycobacteria and their immune-active molecules. In addition, common monocyte progenitors accumulate cholesterol and lipids, which are prerequisites for giant cell transformation. Inducible monocyte progenitors are so far undescribed circulating common monocyte progenitor descendants with high giant cell-forming potential. Monocyte progenitors are induced in mycobacterial infections and localize to granulomas. Accordingly, they exhibit important immunological functions in mycobacterial infections. Moreover, their signature trait of high cholesterol metabolism may be piggy-backed by mycobacteria to create a permissive niche.


Subject(s)
Cytokines/immunology , Giant Cells/immunology , Macrophages/immunology , Monocytes/immunology , Stem Cells/immunology , Animals , Cells, Cultured , Cytokines/metabolism , Female , Giant Cells/metabolism , Giant Cells/microbiology , Granuloma/immunology , Granuloma/metabolism , Humans , Macrophages/metabolism , Macrophages/microbiology , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Monocytes/metabolism , Monocytes/microbiology , Mycobacterium/immunology , Mycobacterium/physiology , Stem Cells/metabolism , Stem Cells/microbiology
17.
Front Immunol ; 12: 782495, 2021.
Article in English | MEDLINE | ID: mdl-35003097

ABSTRACT

The mycobacterium genus contains a broad range of species, including the human pathogens M. tuberculosis and M. leprae. These bacteria are best known for their residence inside host cells. Neutrophils are frequently observed at sites of mycobacterial infection, but their role in clearance is not well understood. In this review, we discuss how neutrophils attempt to control mycobacterial infections, either through the ingestion of bacteria into intracellular phagosomes, or the release of neutrophil extracellular traps (NETs). Despite their powerful antimicrobial activity, including the production of reactive oxidants such as hypochlorous acid, neutrophils appear ineffective in killing pathogenic mycobacteria. We explore mycobacterial resistance mechanisms, and how thwarting neutrophil action exacerbates disease pathology. A better understanding of how mycobacteria protect themselves from neutrophils will aid the development of novel strategies that facilitate bacterial clearance and limit host tissue damage.


Subject(s)
Host-Pathogen Interactions/immunology , Mycobacterium Infections/immunology , Mycobacterium Infections/microbiology , Mycobacterium/immunology , Neutrophils/immunology , Neutrophils/metabolism , Animals , Biomarkers , Cytotoxicity, Immunologic , Disease Susceptibility/immunology , Extracellular Traps/genetics , Extracellular Traps/immunology , Host-Pathogen Interactions/genetics , Humans , Immunity, Innate , Mycobacterium Infections/diagnosis , Mycobacterium Infections/metabolism , Neutrophil Activation/genetics , Neutrophil Activation/immunology , Neutrophils/microbiology , Neutrophils/pathology , Oxidants/metabolism , Oxidative Stress , Phagocytosis/genetics , Phagocytosis/immunology , Phagosomes/metabolism
18.
J Microbiol Immunol Infect ; 54(3): 437-446, 2021 Jun.
Article in English | MEDLINE | ID: mdl-32146163

ABSTRACT

BACKGROUND/PURPOSE: The World Health Organization has recommended commercial urine-sourced lipoarabinomannan (LAM) detection as a tool for screening HIV patients with suspected TB, but more sensitive immunodetection assays would help to identify HIV-negative TB patients. Here, we aimed to develop novel rabbit monoclonal antibodies (mAbs) against LAM for immunodetection purposes. METHODS: Rabbits were immunized with cell-wall components from the Mycobacterium tuberculosis (Mtb) H37Rv strain. An immune single-chain fragment variable (scFv) phage display library was generated. The scFv mAbs to LAM were identified through ELISA screening. The light and heavy chain variable region genes from the selected clones were sequenced. Vectors containing the full-length light and heavy chains were constructed and co-expressed in 293 T cells to generate whole IgG antibodies. The performances and binding characteristics of the mAbs against purified LAM from M.tb H37Rv, multiple mycobacteria species (M.tb H37Rv, M. bovis and non-tuberculous mycobacteria (NTM) strains), and mycobacteria clinical isolates (Mtb and NTM isolates) were determined using various immunoassay methods. RESULTS: We obtained five rabbit mAbs against LAM, four of which had high sensitivities (100 pg/ml) and affinities (1.16-1.73 × 10-9 M) toward LAM. They reacted with M.tb H37Rv, M. bovis, and slow-growing NTM, but not with rapid-growing NTM. Similar results were obtained with mycobacterium isolates, where 96% of the Mtb isolates and 90% of the M. avium-intracellulare isolates were successfully identified. CONCLUSION: The novel rabbit LAM-specific mAbs performed well at recognizing LAM from slow-growing pathogenic mycobacteria, which support their future clinical application.


Subject(s)
Antibodies, Monoclonal/immunology , Immunoassay/methods , Lipopolysaccharides/immunology , Mycobacterium tuberculosis/immunology , Mycobacterium/immunology , Tuberculosis/diagnosis , Animals , Antibodies, Monoclonal/isolation & purification , Cell Surface Display Techniques , Humans , Immunoassay/standards , Mycobacterium/classification , Mycobacterium/pathogenicity , Mycobacterium tuberculosis/chemistry , Nontuberculous Mycobacteria/immunology , Rabbits , Tuberculosis/immunology , Tuberculosis/microbiology
19.
Vet Microbiol ; 253: 108952, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33370619

ABSTRACT

Mycobacterium caprae, a member of the Mycobacterium tuberculosis complex, infects humans and animals causing lesions and disease like that of Mycobacterium bovis. The aim of this study was to evaluate antibody responses in European Bison (EB, Bison bonasus; a vulnerable species) naturally infected with M. caprae using dual path platform (DPP) BovidTB test and multi-antigen print immunoassay (MAPIA). Study cohorts consisted of naturally M. caprae-infected EB (n = 4), M. caprae-exposed but uninfected (n = 3), EB infected with non-tuberculous mycobacteria or other respiratory pathogens (n = 3), and negative controls (n = 19). M. caprae-infected EB were seropositive by both DPP and MAPIA; 3/4 were seropositive by DPP; and 4/4 were seropositive by MAPIA. One M. caprae-infected animal that developed generalized disease with most advanced gross lesions in the group produced the most robust antibody response. All 25 EB with no culture-confirmed M. caprae infection, including three animals exposed to M. caprae and three other animals infected with non-tuberculous pathogens, were seronegative on both tests. Antibody responses to M. caprae infection included IgM antibodies against MPB70/MPB83 and IgG antibodies to both MPB70/MPB83 and CFP10/ESAT-6. This study demonstrates the potential for use of serological assays in the ante-mortem diagnosis of M. caprae infection in EB.


Subject(s)
Antibodies, Bacterial/blood , Antibody Formation , Bison/microbiology , Mycobacterium Infections/immunology , Mycobacterium Infections/veterinary , Mycobacterium/immunology , Animals , Animals, Wild/microbiology , Bison/immunology , Immunoassay , Immunoglobulin G/blood , Immunoglobulin M/blood , Mycobacterium/classification
20.
Cell ; 183(7): 1826-1847.e31, 2020 12 23.
Article in English | MEDLINE | ID: mdl-33296702

ABSTRACT

Inborn errors of human interferon gamma (IFN-γ) immunity underlie mycobacterial disease. We report a patient with mycobacterial disease due to inherited deficiency of the transcription factor T-bet. The patient has extremely low counts of circulating Mycobacterium-reactive natural killer (NK), invariant NKT (iNKT), mucosal-associated invariant T (MAIT), and Vδ2+ γδ T lymphocytes, and of Mycobacterium-non reactive classic TH1 lymphocytes, with the residual populations of these cells also producing abnormally small amounts of IFN-γ. Other lymphocyte subsets develop normally but produce low levels of IFN-γ, with the exception of CD8+ αß T and non-classic CD4+ αß TH1∗ lymphocytes, which produce IFN-γ normally in response to mycobacterial antigens. Human T-bet deficiency thus underlies mycobacterial disease by preventing the development of innate (NK) and innate-like adaptive lymphocytes (iNKT, MAIT, and Vδ2+ γδ T cells) and IFN-γ production by them, with mycobacterium-specific, IFN-γ-producing, purely adaptive CD8+ αß T, and CD4+ αß TH1∗ cells unable to compensate for this deficit.


Subject(s)
Adaptive Immunity , Immunity, Innate , Interferon-gamma/immunology , Mycobacterium/immunology , T-Box Domain Proteins/metabolism , Amino Acid Sequence , Base Sequence , Cell Lineage , Child, Preschool , Chromatin/metabolism , CpG Islands/genetics , DNA Methylation/genetics , Dendritic Cells/metabolism , Epigenesis, Genetic , Female , Homozygote , Humans , INDEL Mutation/genetics , Infant , Interferon-gamma/metabolism , Killer Cells, Natural/cytology , Killer Cells, Natural/metabolism , Loss of Function Mutation/genetics , Male , Mycobacterium Infections/genetics , Mycobacterium Infections/immunology , Mycobacterium Infections/microbiology , Pedigree , T-Box Domain Proteins/chemistry , T-Box Domain Proteins/deficiency , T-Box Domain Proteins/genetics , T-Lymphocytes, Helper-Inducer/immunology , Transcriptome/genetics
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