Immune-Responsive Gene 1 expression in myeloid cells prevents neutrophil mediated immunopathology during Mycobacterium tuberculosis infection.
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE98458 | GEO | 2017/08/30
SECONDARY ACCESSION(S): PRJNA385136
REPOSITORIES: GEO
Similar Datasets
Project description:Immune-Responsive Gene 1 (Irg1) is a mitochondrial enzyme that produces itaconate under inflammatory conditions principally in cells of myeloid lineage. Cell culture studies suggest that itaconate regulates inflammation through inhibitory effects on cytokine and reactive oxygen species production. To evaluate the functions of Irg1 in vivo, we challenged wild-type (WT) and Irg1-/- mice with Mycobacterium tuberculosis (Mtb) and monitored disease progression. Irg1-/- but not WT mice succumbed rapidly to Mtb, and mortality was associated with increased infection, inflammation, and pathology. Infection of LysM-Cre Irg1fl/fl, MPR8-Cre Irg1fl/fl, and CD11c-Cre Irg1fl/fl conditional knockout mice along with neutrophil depletion experiments revealed a role for Irg1 in alveolar macrophages and LysM+ myeloid cells in preventing neutrophil-mediated immunopathology and disease. RNA-seq analyses suggest that Irg1 and its production of itaconate temper Mtb-induced inflammatory responses in myeloid cells at the transcriptional level. Thus, Irg1 modulates inflammation to curtail Mtb-induced lung disease.
2018-02-15 | GSE108188 | GEO
Project description:Immune-Responsive Gene 1 (Irg1) is a mitochondrial enzyme that produces itaconate under inflammatory conditions principally in cells of myeloid lineage. Cell culture studies suggest that itaconate regulates inflammation through inhibitory effects on cytokine and reactive oxygen species production. To evaluate the functions of Irg1 in vivo, we challenged wild-type (WT) and Irg1 KO mice with Mycobacterium tuberculosis (Mtb) and monitored disease progression. Irg1 KO but not WT mice succumbed rapidly to Mtb, and mortality was associated with increased infection, inflammation, and pathology. Infection of LysM-Cre Irg1 flox, MPR8-Cre Irg1 flox, and CD11c-Cre Irg1 flox conditional knockout mice along with neutrophil depletion experiments revealed a role for Irg1 in alveolar macrophages and LysM+ myeloid cells in preventing neutrophil-mediated immunopathology and disease. RNA-seq analyses suggest that Irg1 and its production of itaconate temper Mtb-induced inflammatory responses in myeloid cells at the transcriptional level. Thus, Irg1 modulates inflammation to curtail Mtb-induced lung disease.
2017-08-30 | GSE98457 | GEO
Project description:Immune-Responsive Gene 1 (Irg1) is a mitochondrial enzyme that produces itaconate under inflammatory conditions principally in cells of myeloid lineage. Cell culture studies suggest that itaconate regulates inflammation through inhibitory effects on cytokine and reactive oxygen species production. To evaluate the functions of Irg1 in vivo, we challenged wild-type (WT) and Irg1 KO mice with Mycobacterium tuberculosis (Mtb) and monitored disease progression. Irg1 KO but not WT mice succumbed rapidly to Mtb, and mortality was associated with increased infection, inflammation, and pathology. Infection of LysM-Cre Irg1 flox, MPR8-Cre Irg1 flox, and CD11c-Cre Irg1 flox conditional knockout mice along with neutrophil depletion experiments revealed a role for Irg1 in alveolar macrophages and LysM+ myeloid cells in preventing neutrophil-mediated immunopathology and disease. RNA-seq analyses suggest that Irg1 and its production of itaconate temper Mtb-induced inflammatory responses in myeloid cells at the transcriptional level. Thus, Irg1 modulates inflammation to curtail Mtb-induced lung disease.
2017-08-30 | GSE98456 | GEO
Project description:Immune-Responsive Gene 1 expression in myeloid cells prevents neutrophil mediated immunopathology during Mycobacterium tuberculosis infection.
| PRJNA385136 | ENA
Project description:Immune-Responsive Gene 1 expression in myeloid cells prevents neutrophil mediated immunopathology during Mycobacterium tuberculosis infection [macrophage]
| PRJNA422778 | ENA
Project description:The W-Beijing strain family is globally distributed and is associated with multidrug-resistant tuberculosis (TB) and treatment failure. Therefore, in this study, we examined the contribution of Toll-like receptor 2 (TLR2) to host resistance against Mycobacterium tuberculosis HN878, a clinical isolate belonging to the W-Beijing family. We show that TLR2 knockout (TLR2KO) mice infected with M. tuberculosis HN878 exhibit increased bacterial burden and are unable to control tissue-damaging, pulmonary neutrophilic inflammation. Consistent with a critical role for CXCL5 in regulating neutrophil influx, expression of epithelial cell-derived CXCL5 is significantly enhanced in TLR2KO mice prior to their divergence from wild-type (WT) mice in M. tuberculosis replication and neutrophilic inflammation. Depletion of neutrophils in TLR2KO mice by targeting Ly6G reverts lung inflammation and bacterial burden to levels comparable to those of WT mice. Together, the results establish that TLR2 controls neutrophil-driven immunopathology during infection with M. tuberculosis HN878 infection, likely by curtailing CXCL5 production.
| S-EPMC6386542 | biostudies-literature
Project description:Mycobacterium tuberculosis, a major global health threat, replicates in macrophages in part by inhibiting phagosome-lysosome fusion, until interferon-? (IFN?) activates the macrophage to traffic M. tuberculosis to the lysosome. How IFN? elicits this effect is unknown, but many studies suggest a role for macroautophagy (herein termed autophagy), a process by which cytoplasmic contents are targeted for lysosomal degradation. The involvement of autophagy has been defined based on studies in cultured cells where M. tuberculosis co-localizes with autophagy factors ATG5, ATG12, ATG16L1, p62, NDP52, BECN1 and LC3 (refs 2-6), stimulation of autophagy increases bacterial killing, and inhibition of autophagy increases bacterial survival. Notably, these studies reveal modest (~1.5-3-fold change) effects on M. tuberculosis replication. By contrast, mice lacking ATG5 in monocyte-derived cells and neutrophils (polymorponuclear cells, PMNs) succumb to M. tuberculosis within 30 days, an extremely severe phenotype similar to mice lacking IFN? signalling. Importantly, ATG5 is the only autophagy factor that has been studied during M. tuberculosis infection in vivo and autophagy-independent functions of ATG5 have been described. For this reason, we used a genetic approach to elucidate the role for multiple autophagy-related genes and the requirement for autophagy in resistance to M. tuberculosis infection in vivo. Here we show that, contrary to expectation, autophagic capacity does not correlate with the outcome of M. tuberculosis infection. Instead, ATG5 plays a unique role in protection against M. tuberculosis by preventing PMN-mediated immunopathology. Furthermore, while Atg5 is dispensable in alveolar macrophages during M. tuberculosis infection, loss of Atg5 in PMNs can sensitize mice to M. tuberculosis. These findings shift our understanding of the role of ATG5 during M. tuberculosis infection, reveal new outcomes of ATG5 activity, and shed light on early events in innate immunity that are required to regulate disease pathology and bacterial replication.
| S-EPMC4842313 | biostudies-literature
Project description:Immune-Responsive Gene 1 (Irg1) is a mitochondrial enzyme that produces itaconate under inflammatory conditions, principally in cells of myeloid lineage. Cell culture studies suggest that itaconate regulates inflammation through its inhibitory effects on cytokine and reactive oxygen species production. To evaluate the functions of Irg1 in vivo, we challenged wild-type (WT) and Irg1-/- mice with Mycobacterium tuberculosis (Mtb) and monitored disease progression. Irg1-/-, but not WT, mice succumbed rapidly to Mtb, and mortality was associated with increased infection, inflammation, and pathology. Infection of LysM-Cre Irg1fl/fl, Mrp8-Cre Irg1fl/fl, and CD11c-Cre Irg1fl/fl conditional knockout mice along with neutrophil depletion experiments revealed a role for Irg1 in LysM+ myeloid cells in preventing neutrophil-mediated immunopathology and disease. RNA sequencing analyses suggest that Irg1 and its production of itaconate temper Mtb-induced inflammatory responses in myeloid cells at the transcriptional level. Thus, an Irg1 regulatory axis modulates inflammation to curtail Mtb-induced lung disease.
| S-EPMC5881474 | biostudies-literature
Project description:Tissue factor (TF) is a transmembrane glycoprotein that plays an essential role in hemostasis by activating coagulation. TF is also expressed by monocytes/macrophages as part of the innate immune response to infections. In the current study, we determined the role of TF expressed by myeloid cells during Mycobacterium tuberculosis (M. tb) infection by using mice lacking the TF gene in myeloid cells (TF(?) ) and human monocyte derived macrophages (MDMs). We found that during M. tb infection, a deficiency of TF in myeloid cells was associated with reduced inducible nitric oxide synthase (iNOS) expression, enhanced arginase 1 (Arg1) expression, enhanced IL-10 production and reduced apoptosis in infected macrophages, which augmented M. tb growth. Our results demonstrate that a deficiency of TF in myeloid cells promotes M2-like phenotype in M .tb infected macrophages. A deficiency in TF expression by myeloid cells was also associated with reduced fibrin deposition and increased matrix metalloproteases (MMP)-2 and MMP-9 mediated inflammation in M. tb infected lungs. Our studies demonstrate that TF expressed by myeloid cells has newly recognized abilities to polarize macrophages and to regulate M. tb growth.
| S-EPMC4740218 | biostudies-literature
Project description:Targeting Mycobacterium tuberculosis bacilli in low-oxygen microenvironments, such as caseous granulomas, has been hypothesized to have the potential to shorten therapy for active tuberculosis (TB) and prevent reactivation of latent infection. We previously reported that upon low-dose M. tuberculosis infection, equal proportions of cynomolgus macaques develop active disease or latent infection and that latently infected animals reactivated upon neutralization of TNF. Using this model we now show that chemoprophylaxis of latently infected cynomolgus macaques with 6 mo of isoniazid (INH) effectively prevented anti-TNF antibody-induced reactivation. Similarly, 2-mo treatment of latent animals with a combination of INH and rifampicin (RIF) was highly effective at preventing reactivation disease in this model. Metronidazole (MTZ), which has activity only against anaerobic, nonreplicating bacteria, was as effective as either of these treatments in preventing reactivation of latent infection. Because hypoxic lesions also occur during active TB, we further showed that addition of MTZ to INH/RIF effectively treated animals with active TB within 2 mo. Healing lesions were associated with distinct changes in cellular pathology, with a shift toward increasingly fibrotic and calcified lesions. Our data in the nonhuman primate model of active and latent TB supports targeting bacteria in hypoxic environments for preventing reactivation of latent infection and possibly shortening the duration of therapy in active TB.
| S-EPMC3435210 | biostudies-literature