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An Amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Tuberculosis is the leading cause of death by an infectious disease worldwide1. However, the involvement of innate lymphoid cells (ILCs) in immune responses to infection with Mycobacterium tuberculosis (Mtb) is unknown. Here we show that circulating subsets of ILCs are depleted from the blood of participants with pulmonary tuberculosis and restored upon treatment. Tuberculosis increased accumulation of ILC subsets in the human lung, coinciding with a robust transcriptional response to infection, including a role in orchestrating the recruitment of immune subsets. Using mouse models, we show that group 3 ILCs (ILC3s) accumulated rapidly in Mtb-infected lungs and coincided with the accumulation of alveolar macrophages. Notably, mice that lacked ILC3s exhibited a reduction in the accumulation of early alveolar macrophages and decreased Mtb control. We show that the C-X-C motif chemokine receptor 5 (CXCR5)-C-X-C motif chemokine ligand 13 (CXCL13) axis is involved in Mtb control, as infection upregulates CXCR5 on circulating ILC3s and increases plasma levels of its ligand, CXCL13, in humans. Moreover, interleukin-23-dependent expansion of ILC3s in mice and production of interleukin-17 and interleukin-22 were found to be critical inducers of lung CXCL13, early innate immunity and the formation of protective lymphoid follicles within granulomas. Thus, we demonstrate an early protective role for ILC3s in immunity to Mtb infection.
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Imunidade Inata/imunologia , Linfócitos/classificação , Linfócitos/imunologia , Macrófagos Alveolares/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia , Animais , Quimiocina CXCL13/imunologia , Feminino , Granuloma/imunologia , Granuloma/patologia , Humanos , Interleucina-17/imunologia , Interleucinas/imunologia , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Linfócitos/metabolismo , Macrófagos Alveolares/metabolismo , Masculino , Camundongos , Receptores CXCR5/imunologia , Transcriptoma/genética , Tuberculose Pulmonar/genética , Interleucina 22RESUMO
Ectopic or tertiary lymphoid tissues, such as inducible bronchus-associated lymphoid tissue (iBALT), form in nonlymphoid organs after local infection or inflammation. However, the initial events that promote this process remain unknown. Here we show that iBALT formed in mouse lungs as a consequence of pulmonary inflammation during the neonatal period. Although we found CD4(+)CD3(-) lymphoid tissue-inducer cells (LTi cells) in neonatal lungs, particularly after inflammation, iBALT was formed in mice that lacked LTi cells. Instead, we found that interleukin 17 (IL-17) produced by CD4(+) T cells was essential for the formation of iBALT. IL-17 acted by promoting lymphotoxin-α-independent expression of the chemokine CXCL13, which was important for follicle formation. Our results suggest that IL-17-producing T cells are critical for the development of ectopic lymphoid tissues.
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Brônquios/imunologia , Tecido Linfoide/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Quimiocina CXCL13/biossíntese , Quimiocina CXCL13/imunologia , Interleucina-17/imunologia , Linfotoxina-alfa/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pneumonia/imunologia , Linfócitos T Auxiliares-Indutores/imunologiaRESUMO
Thy1 (CD90), a glycosylated, glycophosphatidylinositol-anchored membrane protein highly expressed by subsets of mesenchymal stem cells and fibroblasts, inhibits adipogenesis. The role of Thy1 on bone structure and function has been poorly studied and represents a major knowledge gap. Therefore, we analyzed the long bones of wild-type (WT) and Thy1 knockout (KO) mice with micro-computed tomography (micro-CT) and histomorphometry to compare changes in bone architecture and overall bone structure. micro-CT analysis of long bones revealed Thy1 KO and WT mice fed a high-fat diet demonstrated bone structural parameters at 4 mo that differed significantly between WT and KO mice. A significant reduction in trabecular bone volume was noted in Thy1 KO mice. The most prominent differences were observed in trabecular bone volume ratio and trabecular bone connectivity density. Consistent with micro-CT measurements, histomorphometric analysis also showed decreased bone volume in the obese Thy1 KO mice compared to obese WT mice. In vitro assays revealed that osteogenic conditions increased Thy1 expression during OB differentiation and absence of Thy1 attenuated osteoblastogenesis. Together, these findings support the concept that Thy1 serves as a major mechanistic link to regulate bone formation and negatively regulate adipogenesis.-Paine, A., Woeller, C. F., Zhang, H., Garcia-Hernandez, M. L., Huertas, N., Xing, L., Phipps, R. P., Ritchlin, C. T. Thy1 is a positive regulator of osteoblast differentiation and modulates bone homeostasis in obese mice.
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Osso Esponjoso/metabolismo , Diferenciação Celular , Homeostase , Obesidade/metabolismo , Osteoblastos/metabolismo , Antígenos Thy-1/biossíntese , Adipogenia/genética , Animais , Osso Esponjoso/diagnóstico por imagem , Osso Esponjoso/patologia , Camundongos , Camundongos Knockout , Camundongos Obesos , Obesidade/genética , Obesidade/patologia , Osteoblastos/patologia , Antígenos Thy-1/genética , Microtomografia por Raio-XRESUMO
Psoriatic arthritis (PsA) is a complex inflammatory disease that challenges diagnosis and complicates the rational selection of effective therapies. Although T cells are considered active effectors in psoriasis and PsA, the role of CD8+ T cells in pathogenesis is not well understood. We selected the humanized mouse model NSG-SGM3 transgenic strain to examine psoriasis and PsA endotypes. Injection of PBMCs and sera from patients with psoriasis and PsA generated parallel skin and joint phenotypes in the recipient mouse. The transfer of human circulating memory T cells was followed by migration and accumulation in the skin and synovia of these immunodeficient mice. Unexpectedly, immunoglobulins were required for recapitulation of the clinical phenotype of psoriasiform lesions and PsA domains (dactylitis, enthesitis, bone erosion). Human CD8+ T cells expressing T-bet, IL-32 and CXCL14 were detected by spatial transcriptomics in murine synovia and by immunofluorescence in the human PsA synovia. Importantly, depletion of human CD8+ T cells prevented skin and synovial inflammation in mice humanized with PsA peripheral blood cells. The humanized model of psoriasis and PsA represents a valid platform for accelerating the understanding of disease pathogenesis, improving the design of personalized therapies, and revealing psoriatic disease targets.
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Artrite Psoriásica , Linfócitos T CD8-Positivos , Modelos Animais de Doenças , Animais , Artrite Psoriásica/imunologia , Artrite Psoriásica/patologia , Humanos , Camundongos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Camundongos Transgênicos , Pele/patologia , Pele/imunologia , Feminino , Masculino , Fenótipo , Psoríase/imunologia , Psoríase/patologiaRESUMO
OBJECTIVE: The transition from psoriasis to psoriatic arthritis (PsA) occurs in 20-30% of patients; however, the mechanisms underlying the emergence of musculoskeletal disease are not well understood. Metabolic disease is prevalent in psoriasis patients, but whether metabolic factors, other than obesity, increase arthritis risk in psoriasis patients is not known. This study was undertaken to investigate the link between metabolic changes and disease progression in psoriasis patients. METHODS: To characterize the metabolic alterations during the progression of arthritis in psoriasis patients, we analyzed cross-sectional healthy controls and PsA samples and longitudinal psoriasis serum samples, before and after PsA onset. Nontargeted metabolomic profiling was performed using liquid chromatography mass spectrometry. RESULTS: We identified several serum metabolites that differed between PsA patients, psoriasis patients, and healthy controls. Differentially abundant bile acids, purines, pyrimidines, glutathione, lipids, and amino acid metabolites were noted in these 3 groups. We also noted differences between psoriasis patients who progressed and those who did not progress to PsA. Bile acid and butyrate levels were depressed in those who progressed to PsA compared to those who did not, and the level of inflammatory lipid mediators increased following PsA diagnosis. In particular, the combination of leukotriene B4 and glycoursodeoxycholic acid sulfate were sensitive and specific predictors of PsA progression. CONCLUSION: We observed notable differences in bile acid, purine, lipid, and amino acid-derived metabolites, among the healthy controls, psoriasis patients, and PsA patients and identified changes during the transition from psoriasis to PsA. The decreased bile acid and butyrate levels and elevated guanine levels in psoriasis patients at risk for PsA were particularly striking and may reflect gut microbial dysbiosis and dysregulated hepatic metabolism, leading to altered proliferation of immune cells and enhanced cytokine expression.
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Artrite Psoriásica , Psoríase , Humanos , Artrite Psoriásica/diagnóstico , Ácidos e Sais Biliares , Nucleotídeos , Estudos Transversais , Lipídeos , AminoácidosRESUMO
Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb) latently infects approximately one-fourth of the world's population. The immune mechanisms that govern progression from latent (LTBI) to active pulmonary TB (PTB) remain poorly defined. Experimentally Mtb-infected non-human primates (NHP) mirror the disease observed in humans and recapitulate both PTB and LTBI. We characterized the lung immune landscape in NHPs with LTBI and PTB using high-throughput technologies. Three defining features of PTB in macaque lungs include the influx of plasmacytoid dendritic cells (pDCs), an Interferon (IFN)-responsive macrophage population, and activated T cell responses. In contrast, a CD27+ Natural killer (NK) cell subset accumulated in the lungs of LTBI macaques. This NK cell population was also detected in the circulation of LTBI individuals. This comprehensive analysis of the lung immune landscape will improve the understanding of TB immunopathogenesis, providing potential targets for therapies and vaccines for TB control.
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Células Dendríticas/imunologia , Células Matadoras Naturais/imunologia , Tuberculose Latente/imunologia , Macrófagos/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/imunologia , Animais , Humanos , Pulmão/citologia , Pulmão/imunologia , Macaca mulatta , Tuberculose Pulmonar/patologiaRESUMO
RNA helicases are widely conserved key enzymes that perform multiple functions in RNA metabolism. Here, we present the cloning, expression and functional characterization of the EhDEAD1 RNA helicase in the protozoan parasite Entamoeba histolytica. According to its primary structure, EhDEAD1 is evolutionary related to yeast DED1 and human DDX3X RNA helicases, both involved in translation and cell cycle regulation. The EhDEAD1 predicted amino acid sequence exhibits the nine conserved motifs described for the DEAD-box SFII superfamily members reported in other organisms and it is evolutionary close to protozoan homologues. Purified recombinant EhDEAD1 protein presented ATPase activity and it was able to bind and unwind RNA in an ATPase-dependent manner in vitro. RT-PCR assays showed that EhDead1 gene is overtranscribed in the cell cycle S phase. Moreover, inhibition of EhDead1 gene expression by antisense RNA seemed to facilitate transition from S to G2/M phase. Intriguingly, our results showed that EhDEAD1 was unable to rescue two yeast Ded1 RNA helicase mutants affected in translation, in spite of the high sequence homology with yeast DED1.
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Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , RNA Helicases DEAD-box/metabolismo , Entamoeba histolytica/enzimologia , RNA de Protozoário/genética , Sequência de Aminoácidos , Animais , Sequência Conservada , RNA Helicases DEAD-box/genética , Ensaio de Desvio de Mobilidade Eletroforética , Entamoeba histolytica/genética , Entamoeba histolytica/crescimento & desenvolvimento , Teste de Complementação Genética , Lasers , Dados de Sequência Molecular , Filogenia , RNA Mensageiro , RNA de Protozoário/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fase S/fisiologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Homologia de Sequência de AminoácidosRESUMO
Mycobacterium tuberculosis (Mtb) is a global health threat, compounded by the emergence of drug-resistant strains. A hallmark of pulmonary tuberculosis (TB) is the formation of hypoxic necrotic granulomas, which upon disintegration, release infectious Mtb. Furthermore, hypoxic necrotic granulomas are associated with increased disease severity and provide a niche for drug-resistant Mtb. However, the host immune responses that promote the development of hypoxic TB granulomas are not well described. Using a necrotic Mtb mouse model, we show that loss of Mtb virulence factors, such as phenolic glycolipids, decreases the production of the proinflammatory cytokine IL-17 (also referred to as IL-17A). IL-17 production negatively regulates the development of hypoxic TB granulomas by limiting the expression of the transcription factor hypoxia-inducible factor 1α (HIF1α). In human TB patients, HIF1α mRNA expression is increased. Through genotyping and association analyses in human samples, we identified a link between the single nucleotide polymorphism rs2275913 in the IL-17 promoter (-197G/G), which is associated with decreased IL-17 production upon stimulation with Mtb cell wall. Together, our data highlight a potentially novel role for IL-17 in limiting the development of hypoxic necrotic granulomas and reducing disease severity in TB.
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Granuloma/imunologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia , Interleucina-17/imunologia , Tuberculose Pulmonar/imunologia , Adulto , Idoso , Animais , Hipóxia Celular/imunologia , Feminino , Regulação da Expressão Gênica/imunologia , Granuloma/microbiologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Mediadores da Inflamação/metabolismo , Interleucina-17/biossíntese , Masculino , Camundongos Endogâmicos , Pessoa de Meia-Idade , RNA Mensageiro/genética , Tuberculose Pulmonar/complicações , Adulto JovemRESUMO
The acute period after total body irradiation (TBI) is associated with an increased risk of infection, principally resulting from the loss of hematopoietic stem cells, as well as disruption of mucosal epithelial barriers. Although there is a return to baseline infection control coinciding with the apparent progressive recovery of hematopoietic cell populations, late susceptibility to infection in radiation-sensitive organs such as lung and kidney is known to occur. Indeed, pulmonary infections are particularly prevalent in hematopoietic cell transplant (HCT) survivors, in both adult and pediatric patient populations. Preclinical studies investigating late outcomes from localized thoracic irradiation have indicated that the mechanisms underlying pulmonary delayed effects are multifactorial, including exacerbated and persistent production of pro-inflammatory molecules and abnormal cross-talk among parenchymal and infiltrating immune and inflammatory cell populations. However, in the context of low-dose TBI, it is not clear whether the observed exacerbated response to infection remains contingent on these same mechanisms. It is possible instead, that after systemic radiation-induced injury, the susceptibility to infection may be independently related to defects in alternative organs that are revealed only through the challenge itself; indeed, we have hypothesized that this defect may be due to radiation-induced chronic effects in the structure and function of secondary lymphoid organs (SLO). In this study, we investigated the molecular and cellular alterations in SLO (i.e., spleen, mediastinal, inguinal and mesenteric lymph nodes) after TBI, and the time points when there appears to be immune competence. Furthermore, due to the high incidence of pulmonary infections in the late post-transplantation period of bone marrow transplant survivors, particularly in children, we focused on outcomes in mice irradiated as neonates, which served as a model for a pediatric population, and used the induction of adaptive immunity against influenza virus as a functional end point. We demonstrated that, in adult animals irradiated as neonates, high endothelial venule (HEV) expansion, generation of follicular helper T cells (TFH) and formation of splenic germinal centers (GC) were rapidly and, more importantly, persistently impaired in SLO, suggesting that the early-life exposure to sublethal radiation had long-lasting effects on the induction of humoral immunity. Although the neonatal TBI did not affect the overall outcome from influenza infection in the adults at the earlier time points assessed, we believe that they nonetheless contribute significantly to the increased mortality observed at subsequent late time points. Furthermore, we speculate that the detrimental and persistent impact on the induction of CD4 T- and B-cell responses in the mediastinal lymph nodes will decrease the animals' ability to respond to other aerial pathogens. Since many of these pathogens are normally cleared by antibodies, our findings provide an explanation for the susceptibility of survivors of childhood HCT to life-threatening respiratory tract infections. These findings have implications regarding the need for increased monitoring in pediatric hematopoietic cell transplant patients, since they indicate that there are ongoing and cumulative defects in SLO, which, importantly, develop during the immediate and early postirradiation period when patients may appear immunologically competent. The identification of changes in immune-related signals may offer bioindicators of progressive dysfunction, and of potential mechanisms that could be targeted so as to reduce the risk of infection from extracellular pathogens. Furthermore, these results support the potential susceptibility of the pediatric population to infection after sublethal irradiation in the context of a nuclear or radiological event.
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Animais Recém-Nascidos , Tecido Linfoide/efeitos da radiação , Irradiação Corporal Total , Animais , Quimiocinas/metabolismo , Citocinas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Tecido Linfoide/anatomia & histologia , Tecido Linfoide/metabolismo , Tecido Linfoide/fisiologia , Camundongos , Camundongos Endogâmicos C57BLRESUMO
In humans, vWF levels predict the risk of myocardial infarction and thrombosis; however, the factors that influence vWF levels are not completely understood. Recent genome-wide association studies (GWAS) have identified syntaxin-binding protein 5 (STXBP5) as a candidate gene linked to changes in vWF plasma levels, though the functional relationship between STXBP5 and vWF is unknown. We hypothesized that STXBP5 inhibits endothelial cell exocytosis. We found that STXBP5 is expressed in human endothelial cells and colocalizes with and interacts with syntaxin 4. In human endothelial cells reduction of STXBP5 increased exocytosis of vWF and P-selectin. Mice lacking Stxbp5 had higher levels of vWF in the plasma, increased P-selectin translocation, and more platelet-endothelial interactions, which suggests that STXBP5 inhibits endothelial exocytosis. However, Stxbp5 KO mice also displayed hemostasis defects, including prolonged tail bleeding times and impaired mesenteric arteriole and carotid artery thrombosis. Furthermore, platelets from Stxbp5 KO mice had defects in platelet secretion and activation; thus, STXBP5 inhibits endothelial exocytosis but promotes platelet secretion. Our study reveals a vascular function for STXBP5, validates the functional relevance of a candidate gene identified by GWAS, and suggests that variation within STXBP5 is a genetic risk for venous thromboembolic disease.
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Endotélio/metabolismo , Exocitose , Regulação da Expressão Gênica , Proteínas do Tecido Nervoso/metabolismo , Proteínas R-SNARE/metabolismo , Proteínas ADAM/metabolismo , Proteína ADAMTS13 , Animais , Aorta/metabolismo , Plaquetas/citologia , Células Endoteliais/citologia , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Metaloendopeptidases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microcirculação , Proteínas do Tecido Nervoso/genética , Selectina-P/metabolismo , Proteínas Qa-SNARE/metabolismo , Proteínas R-SNARE/genética , Trombose , Fator de von Willebrand/metabolismoRESUMO
Prostate cancer immunotherapy clinical trials have been performed, but often in immunocompromised patients with limited clinical success. The study aim was to determine whether the stage of prostate cancer development at which immunization occurs affects vaccine efficacy, and if so which tumor-associated immunosuppressive mechanisms may be involved at later stages. Therapeutic vaccination of TRAMP mice with only precancerous PIN lesions confered superior protection to immunization after development of invasive carcinoma. The presence of Treg, upregulation of tumor indoleamine-2,3-dioxygenase and TGFbeta and an immunosuppressive intratumoral cytokine milieu were identified in more advanced prostate cancer. These results indicate that prostate cancer immunotherapy trials will be more successful if conducted in patients with less advanced disease.
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Vacinas Anticâncer/uso terapêutico , Imunoterapia/métodos , Estadiamento de Neoplasias , Neoplasias da Próstata/terapia , Animais , Vacinas Anticâncer/imunologia , Proliferação de Células , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Neoplasias da Próstata/imunologia , Linfócitos T Reguladores/imunologia , Fatores de Tempo , Fator de Crescimento Transformador beta/metabolismo , Vacinas de DNA/imunologia , Vacinas de DNA/uso terapêuticoRESUMO
Prostaglandins (PG) are potent mediators of intercellular communication, and PGE2 at high concentration is immunosuppressive for T-cell-mediated immunity. We studied the kinetics of PGE2 production and the expression of the enzymes related to its synthesis during the course of experimental pulmonary tuberculosis. Secondly, we analysed the pathological and immunological changes produced by the pharmacological suppression of PG production. In BALB/c mice infected via the trachea with Mycobacterium tuberculosis H37Rv there is an initial phase of partial resistance, dominated by type 1 cytokines plus tumour necrosis factor-alpha (TNF-alpha) and expression of the inducible form of nitric oxide synthase (iNOS), followed by a phase of progressive disease. During the early phase of the infection some activated macrophages located in the alveolar-capillary interstitium and in granulomas showed strong PGE2 immunostaining. However, PGE2 concentrations were relatively low and stable. Animals in this early phase of infection were treated with niflumic acid, a potent and specific blocker of cyclo-oxygenase 2, the rate-limiting enzyme of PG production. In comparison with control animals, the suppression of PG synthesis produced higher inflammation and expression of TNF-alpha, interleukin-1alpha and interferon-gamma (IFN-gamma), but almost complete disappearance of iNOS expression, which coexisted with a significant increment of bacterial load. The late progressive phase in this experimental model is characterized by progressive pneumonia, small granulomas and diminished expression of IFN-gamma, TNF-alpha and iNOS in coexistence with high expression of IL-4. Strong PGE2 immunostaining was seen in foamy macrophages localized in the pneumonic areas, and the PGE2 concentration was four-fold higher in this late phase of infection than during the early phase. When PG production was suppressed in animals suffering advanced phase infection, a significant reduction of pneumonia and bacillus load with striking increment of granuloma size was seen, and the expression of IFN-gamma, TNF-alpha and iNOS was also improved. These findings demonstrate a significant participation of PGE2 in the pathogenesis of pulmonary tuberculosis, showing that during the early phase of the infection there are low PGE2 concentrations which contribute to iNOS expression permitting the temporal control of bacillus growth, while the high PGE2 concentrations during the late phase of the disease contribute to down-regulate cell-mediated immunity, permitting disease progression.