RESUMO
Placental malaria (PM) is associated with severe inflammation leading to abortion, preterm delivery, and intrauterine growth restriction. Innate immunity responses play critical roles, but the mechanisms underlying placental immunopathology are still unclear. Here, we investigated the role of inflammasome activation in PM by scrutinizing human placenta samples from an endemic area and ablating inflammasome components in a PM mouse model. The reduction in birth weight in babies from infected mothers is paralleled by increased placental expression of AIM2 and NLRP3 inflammasomes. Using genetic dissection, we reveal that inflammasome activation pathways are involved in the production and detrimental action of interleukin-1ß (IL-1ß) in the infected placenta. The IL-1R pharmacological antagonist Anakinra improved pregnancy outcomes by restoring fetal growth and reducing resorption in an experimental model. These findings unveil that IL-1ß-mediated signaling is a determinant of PM pathogenesis, suggesting that IL-1R antagonists can improve clinical outcomes of malaria infection in pregnancy.
Assuntos
Inflamassomos/efeitos dos fármacos , Interleucina-1beta/imunologia , Malária Falciparum/imunologia , Malária/imunologia , Plasmodium falciparum/patogenicidade , Complicações Parasitárias na Gravidez/imunologia , Transdução de Sinais/efeitos dos fármacos , Animais , Caspase 1/genética , Caspase 1/imunologia , Linhagem Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Feminino , Regulação da Expressão Gênica , Humanos , Imunidade Inata , Fatores Imunológicos/farmacologia , Inflamassomos/genética , Inflamassomos/imunologia , Interferon gama/genética , Interferon gama/imunologia , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Interleucina-1beta/antagonistas & inibidores , Interleucina-1beta/genética , Malária/tratamento farmacológico , Malária/genética , Malária/parasitologia , Malária Falciparum/genética , Malária Falciparum/parasitologia , Malária Falciparum/patologia , Camundongos , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Plasmodium berghei/imunologia , Plasmodium berghei/patogenicidade , Plasmodium falciparum/imunologia , Gravidez , Complicações Parasitárias na Gravidez/genética , Complicações Parasitárias na Gravidez/parasitologia , Complicações Parasitárias na Gravidez/prevenção & controle , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/imunologia , Transdução de Sinais/imunologia , Células THP-1 , Trofoblastos/efeitos dos fármacos , Trofoblastos/imunologia , Trofoblastos/parasitologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologiaRESUMO
Diabetes mellitus (DM) encompasses a multitude of secondary disorders, including heart disease. One of the most frequent and potentially life threatening disorders of DM-induced heart disease is ventricular tachycardia (VT). Here we show that toll-like receptor 2 (TLR2) and NLRP3 inflammasome activation in cardiac macrophages mediate the production of IL-1ß in DM mice. IL-1ß causes prolongation of the action potential duration, induces a decrease in potassium current and an increase in calcium sparks in cardiomyocytes, which are changes that underlie arrhythmia propensity. IL-1ß-induced spontaneous contractile events are associated with CaMKII oxidation and phosphorylation. We further show that DM-induced arrhythmias can be successfully treated by inhibiting the IL-1ß axis with either IL-1 receptor antagonist or by inhibiting the NLRP3 inflammasome. Our results establish IL-1ß as an inflammatory connection between metabolic dysfunction and arrhythmias in DM.
Assuntos
Diabetes Mellitus Experimental/imunologia , Interleucina-1beta/imunologia , Macrófagos/imunologia , Miócitos Cardíacos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Taquicardia Ventricular/imunologia , Receptor 2 Toll-Like/imunologia , Potenciais de Ação , Animais , Antirreumáticos/farmacologia , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/imunologia , Arritmias Cardíacas/metabolismo , Cálcio/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Caspase 1/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Inflamassomos/antagonistas & inibidores , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Camundongos , Camundongos Transgênicos , Contração Miocárdica , Miócitos Cardíacos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Potássio/metabolismo , Receptores de Interleucina-1/antagonistas & inibidores , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/imunologia , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/metabolismo , Receptor 2 Toll-Like/genéticaRESUMO
Proinflammatory cytokines are critical mediators that control Mycobacterium tuberculosis (Mtb) growth during active tuberculosis (ATB). To further inhibit bacterial proliferation in diseased individuals, drug inhibitors of cell wall synthesis such as isoniazid (INH) are employed. However, whether INH presents an indirect effect on bacterial growth by regulating host cytokines during ATB is not well known. To examine this hypothesis, we used an in vitro human granuloma system generated with primary leukocytes from healthy donors adapted to model ATB. Intense Mtb proliferation in cell cultures was associated with monocyte/macrophage activation and secretion of IL-1ß and TNF. Treatment with INH significantly reduced Mtb survival, but altered neither T-cell-mediated Mtb killing, nor production of IL-1ß and TNF. However, blockade of both IL-1R1 and TNF signaling rescued INH-induced killing, suggesting synergistic roles of these cytokines in mediating control of Mtb proliferation. Additionally, mycobacterial killing by INH was highly dependent upon drug activation by the pathogen catalase-peroxidase KatG and involved a host PI3K-dependent pathway. Finally, experiments using coinfected (KatG-mutated and H37Rv strains) cells suggested that active INH does not directly enhance host-mediated killing of Mtb. Our results thus indicate that Mtb-stimulated host IL-1 and TNF have potential roles in TB chemotherapy.
Assuntos
Antituberculosos/farmacologia , Interleucina-1beta/imunologia , Isoniazida/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Receptores de Interleucina-1/imunologia , Fator de Necrose Tumoral alfa/imunologia , Proteínas de Bactérias/metabolismo , Células Cultivadas , Humanos , Macrófagos/metabolismo , Monócitos/metabolismo , Fosfatidilinositol 3-Quinases/imunologia , Receptores de Interleucina-1/antagonistas & inibidores , Tuberculose/tratamento farmacológico , Tuberculose/imunologia , Fator de Necrose Tumoral alfa/antagonistas & inibidoresRESUMO
ArtinM is a D-mannose-binding lectin extracted from the seeds of Artocarpus heterophyllus that interacts with TLR2 N-glycans and activates antigen-presenting cells (APCs), as manifested by IL-12 production. In vivo ArtinM administration induces Th1 immunity and confers protection against infection with several intracellular pathogens. In the murine model of Candida albicans infection, it was verified that, in addition to Th1, ArtinM induces Th17 immunity manifested by high IL-17 levels in the treated animals. Herein, we investigated the mechanisms accounting for the ArtinM-induced IL-17 production. We found that ArtinM stimulates the IL-17 production by spleen cells in BALB/c or C57BL/6 mice, a response that was significantly reduced in the absence of IL-23, MyD88, or IL-1R. Furthermore, we showed that ArtinM directly induced the IL-23 mRNA expression and the IL-1 production by macrophages. Consistently, in cell suspensions depleted of macrophages, the IL-17 production stimulated by ArtinM was reduced by 53% and the exogenous IL-23 acted synergistically with ArtinM in promoting IL-17 production by spleen cell suspensions. We verified that the absence of IL-23, IL-1R, or MyD88 inhibited, but did not block, the IL-17 production by ArtinM-stimulated spleen cells. Therefore, we investigated whether ArtinM exerts a direct effect on CD4+ T cells in promoting IL-17 production. Indeed, spleen cell suspensions depleted of CD4+ T cells responded to ArtinM with very low levels of IL-17 release. Likewise, isolated CD4+ T cells under ArtinM stimulus augmented the expression of TGF-ß mRNA and released high levels of IL-17. Considering the observed synergism between IL-23 and ArtinM, we used cells from IL-23 KO mice to assess the direct effect of lectin on CD4+ T cells. We verified that ArtinM increased the IL-17 production significantly, a response that was inhibited when the CD4+ T cells were pre-incubated with anti-CD3 antibody. In conclusion, ArtinM stimulates the production of IL-17 by CD4+ T cells in two major ways: (I) through the induction of IL-23 and IL-1 by APCs and (II) through the direct interaction with CD3 on the CD4+ T cells. This study contributes to elucidation of mechanisms accounting for the property of ArtinM in inducing Th17 immunity and opens new perspectives in designing strategies for modulating immunity by using carbohydrate recognition agents.
Assuntos
Artocarpus/química , Complexo CD3/imunologia , Interleucina-17/imunologia , Interleucina-1/imunologia , Interleucina-23/imunologia , Lectina de Ligação a Manose , Lectinas de Plantas , Células Th17/imunologia , Animais , Complexo CD3/genética , Candida albicans/imunologia , Candidíase/tratamento farmacológico , Candidíase/genética , Candidíase/imunologia , Interleucina-1/genética , Interleucina-17/genética , Interleucina-23/genética , Lectina de Ligação a Manose/química , Lectina de Ligação a Manose/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , Lectinas de Plantas/química , Lectinas de Plantas/farmacologia , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/imunologia , Células Th1/imunologiaRESUMO
Injectable bone substitutes and techniques have been developed for use in minimally invasive procedures for bone augmentation. Objective : To develop a novel injectable thermo-sensitive alginate hydrogel (TSAH) as a scaffold to induce bone regeneration, using a minimally invasive tunnelling technique. Material and Methods : An injectable TSAH was prepared from a copolymer solution of 8.0 wt% Poly(N-isopropylacrylamide) (PNIPAAm) and 8.0 wt% AAlg-g-PNIPAAm. In vitro properties of the material, such as its microstructure and the sustained release of recombinant human bone morphogenetic protein-2 (rhBMP-2), were investigated. Then, with the subperiosteal tunnelling technique, this material, carrying rhBMP-2, was injected under the labial periosteum of the maxillary anterior alveolar ridge in a rabbit model. New bone formation was evaluated by means of X-ray, micro-computed tomography (micro-CT), fluorescence labelling, histological study, and immunohistochemistry study. Results : The material exhibited good injectability and thermo-irreversible properties. SEM showed an interconnected porous microstructure of the TSAH. The result of ALP activity indicated sustained delivery of BMP-2 from the TSAH from days 3 to 15. In a rabbit model, both TSAH and TSAH/rhBMP-2 induced alveolar ridge augmentation. The percentage of mineralised tissue in the TSAH/rhBMP-2 group (41.6±3.79%) was significantly higher than in the TSAH group (31.3±7.21%; p<0.05). The density of the regenerating tissue was higher in the TSAH/rhBMP-2 group than in the other groups (TSAH group, positive control, blank control; p<0.05). Conclusions : The TSAH provided convenient handling properties for clinical application. To some extent, TSAH could induce ridge augmentation and mineral deposition, which can be enhanced when combined with rhBMP-2 for a minimally invasive tunnelling injection. .
Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Lesões Encefálicas/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Receptores de Interleucina-1/antagonistas & inibidores , Lesões Encefálicas/imunologia , Lesões Encefálicas/patologia , Encéfalo/imunologia , Encéfalo/patologia , Citocinas/análise , Citocinas/imunologia , Proteína Antagonista do Receptor de Interleucina 1/administração & dosagem , Proteína Antagonista do Receptor de Interleucina 1/efeitos adversos , Receptores de Interleucina-1/imunologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêuticoRESUMO
BACKGROUND: Chagas disease, caused by the protozoan Trypanosoma cruzi is endemic in Latin America. Thirty percent of infected individuals develop chronic Chagas cardiomyopathy (CCC), an inflammatory dilated cardiomyopathy that is, by far, the most important clinical consequence of T. cruzi infection. The others remain asymptomatic (ASY). A possible genetic component to disease progression was suggested by familial aggregation of cases and the association of markers of innate and adaptive immunity genes with CCC development. Migration of Th1-type T cells play a major role in myocardial damage. METHODS: Our genetic analysis focused on CCR5, CCL2 and MAL/TIRAP genes. We used the Tag SNPs based approach, defined to catch all the genetic information from each gene. The study was conducted on a large Brazilian population including 315 CCC cases and 118 ASY subjects. RESULTS: The CCL2rs2530797A/A and TIRAPrs8177376A/A were associated to an increase susceptibility whereas the CCR5rs3176763C/C genotype is associated to protection to CCC. These associations were confirmed when we restricted the analysis to severe CCC, characterized by a left ventricular ejection fraction under 40%. CONCLUSIONS: Our data show that polymorphisms affecting key molecules involved in several immune parameters (innate immunity signal transduction and T cell/monocyte migration) play a role in genetic susceptibility to CCC development. This also points out to the multigenic character of CCC, each polymorphism imparting a small contribution. The identification of genetic markers for CCC will provide information for pathogenesis as well as therapeutic targets.
Assuntos
Cardiomiopatia Chagásica/genética , Quimiocina CCL2/genética , Predisposição Genética para Doença , Imunidade Inata , Glicoproteínas de Membrana/genética , Receptores CCR5/genética , Receptores de Interleucina-1/genética , Trypanosoma cruzi/fisiologia , Adulto , Idoso , Brasil , Cardiomiopatia Chagásica/imunologia , Cardiomiopatia Chagásica/parasitologia , Cardiomiopatia Chagásica/prevenção & controle , Quimiocina CCL2/imunologia , Feminino , Genótipo , Humanos , Masculino , Glicoproteínas de Membrana/imunologia , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Receptores CCR5/imunologia , Receptores de Interleucina-1/imunologiaRESUMO
INTRODUCTION: Preclinical work has suggested that IL-1 plays a critical role in the pathogenesis of rheumatoid arthritis (RA). The objective of the present study was to determine the effect of a long-acting IL-1 receptor inhibitor, AMG 108, in a double-blind, placebo-controlled, parallel-dosing study in patients with active RA who were receiving stable methotrexate (15 to 25 mg/week). METHODS: Patients were randomized equally to receive placebo or 50, 125, or 250 mg AMG 108 subcutaneously every 4 weeks for 6 months. The primary efficacy endpoint was a 20% improvement in the American College of Rheumatology response (ACR20) at week 24; other efficacy endpoints included the ACR50, the ACR70, and the RA disease activity score (28-joint count Disease Activity Score) responses, patient-reported outcomes, and pharmacokinetic parameters. Safety endpoints included treatment-emergent adverse events (AEs), infectious AEs, serious AEs, serious infections, injection site reactions, laboratory abnormalities, and antibodies to AMG 108. RESULTS: Of 813 patients enrolled in the study, 204 patients were randomized to the 50 mg group, 203 to the 125 mg group, 203 to the 250 mg group, and 203 to placebo. At week 24, 40.4% of the 250 mg group, 36% of the 125 mg group, 30.9% of the 50 mg group, and 29.1% of the placebo group achieved an ACR20 (P = 0.022, 250 mg vs. placebo). Of the individual ACR components, numerical dose-dependent improvements were only seen in tender joint counts, pain (visual analog scale), and the acute phase reactants, erythrocyte sedimentation rate and C-reactive protein. No dose-related increase was observed in the incidence of treatment-emergent AEs. No deaths were reported, and the incidence of AEs and infections, serious AEs and infections, and withdrawals from study for safety were similar in the AMG 108 and placebo groups. CONCLUSIONS: This large double-blind randomized trial with a long-acting IL-1 receptor blocker, AMG 108, is consistent with the experience of other IL-1 blockers, represents a definitive experiment showing that IL-1 inhibition provides only moderate symptomatic amelioration of arthritis activity in the majority of RA patients, and provides an answer to a question that has been discussed for many years in the rheumatologic community. TRIAL REGISTRATION: ClinicalTrials.gov NCT00293826.