RESUMO
The balance of proinflammatory T helper type 17 (TH17) and anti-inflammatory T regulatory (Treg) cells is crucial for immune homeostasis in health and disease. The differentiation of naïve CD4+ T cells into TH17 and Treg cells depends on T cell receptor (TCR) signaling mediated, in part, by interleukin-2-inducible T cell kinase (ITK), which stimulates mitogen-activated protein kinases (MAPKs) and Ca2+ signaling. Here, we report that, in the absence of ITK activity, naïve murine CD4+ T cells cultured under TH17-inducing conditions expressed the Treg transcription factor Foxp3 and did not develop into TH17 cells. Furthermore, ITK inhibition in vivo during allergic inflammation increased the Treg:TH17 ratio in the lung. These switched Foxp3+ Treg-like cells had suppressive function, and their transcriptomic profile resembled that of differentiated, induced Treg (iTreg) cells, but their chromatin accessibility profiles were intermediate between TH17 and iTreg cells. Like iTreg cells, switched Foxp3+ Treg-like cells had reductions in the expression of genes involved in mitochondrial oxidative phosphorylation and glycolysis, in the activation of the mechanistic target of rapamycin (mTOR) signaling pathway, and in the abundance of the TH17 pioneer transcription factor BATF. This ITK-dependent switch between TH17 and Treg cells depended on Ca2+ signaling but not on MAPKs. These findings suggest potential strategies for fine-tuning TCR signal strength through ITK to control the balance of TH17 and Treg cells.
Assuntos
Diferenciação Celular , Fatores de Transcrição Forkhead , Proteínas Tirosina Quinases , Linfócitos T Reguladores , Células Th17 , Animais , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Células Th17/imunologia , Células Th17/citologia , Células Th17/metabolismo , Camundongos , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/imunologia , Proteínas Tirosina Quinases/metabolismo , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/imunologia , Sinalização do Cálcio , Camundongos Endogâmicos C57BL , Cálcio/metabolismo , Camundongos Knockout , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/imunologiaRESUMO
This review article delves into the complexities of granuloma formation, focusing on the metabolic reprogramming within these immune structures, especially in tuberculosis and sarcoidosis. It underscores the role of the monocyte-macrophage lineage in granuloma formation and maintenance, emphasizing the adaptability of these cells to environmental cues and inflammatory stimuli. Key to the discussion is the macrophage polarization influenced by various cytokines, with a detailed exploration of the metabolic shifts towards glycolysis under hypoxic conditions and the utilization of the pentose phosphate pathway (PPP) for crucial biosynthetic processes. Significant attention is given to the metabolism of L-arginine in macrophages and its impact on immune response and granuloma function. The review also highlights the role of mechanistic target of rapamycin (mTOR) signaling in macrophage differentiation and its implications in granulomatous diseases. Discoveries such as elevated PPP activity in granuloma-associated macrophages and the protective role of NADPH against oxidative stress offer novel insights into granuloma biology. The review concludes by suggesting potential therapeutic targets within these metabolic pathways to modulate granuloma formation and function, proposing new treatment avenues for conditions characterized by chronic inflammation and granuloma formation. This work contributes significantly to the understanding of immune regulation and chronic inflammation, presenting avenues for future research and therapy in granulomatous diseases.
Assuntos
Granuloma , Macrófagos , Humanos , Macrófagos/imunologia , Macrófagos/metabolismo , Granuloma/imunologia , Granuloma/patologia , Animais , Via de Pentose Fosfato/imunologia , Transdução de Sinais/imunologia , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/imunologia , Ativação de Macrófagos/imunologia , Glicólise/imunologia , Reprogramação MetabólicaRESUMO
Introduction: Vascular smooth muscle cells (VSMCs) are highly involved in airway vascular remodeling in asthma. Objectives: This study aimed to investigate the mechanisms underlying the effects of a disintegrin and metalloproteinase-33 (ADAM33) gene on the migration capacity and inflammatory cytokine secretion of VSMCs. Methods: Human aortic smooth muscle cells (HASMCs) were transfected with lentiviral vectors carrying short hairpin RNA (shRNA) targeting ADAM33 or negative control vectors. The migration capacity of HASMCs was evaluated by a transwell assay. The levels of secreted inflammatory cytokines were measured using enzyme-linked immunosorbent assay (ELISA) kits. Reverse transcription-quantitative polymerase chain reaction and Western blot assays were performed to detect mRNA and protein expression levels. Results: Silencing of ADAM33 significantly inhibited the migration of HASMCs. The expression of tumor necrosis factor alpha (TNF-α) in the supernatant of HASMCs was decreased, while that of interferon gamma (IFN-γ) was increased after the transfection of shRNA targeting ADAM33. Insufficient ADAM33 expression also suppressed the expression levels of phosphatidylinositol 3-kinase (PI3K), phospho-protein kinase B (AKT), phospho-mammalian target of rapamycin (mTOR), Rho-associated protein kinases, phospho-forkhead box protein O1 (FOXO1), and cyclin D1, but it did not affect the levels of AKT, mTOR, or Rho. Conclusion: Silencing of the ADAM33 gene inhibited HASMC migration and regulated inflammatory cytokine secretion via targeting the PI3K/AKT/mTOR pathway and its downstream signaling. These data contribute to a better understanding of the regulatory mechanisms of airway vascular remodeling in asthma.
Assuntos
Proteínas ADAM , Remodelação das Vias Aéreas , Asma , Inativação Gênica , Músculo Liso Vascular , Remodelação Vascular , Proteínas ADAM/genética , Proteínas ADAM/imunologia , Remodelação das Vias Aéreas/genética , Remodelação das Vias Aéreas/imunologia , Asma/genética , Asma/imunologia , Movimento Celular/genética , Movimento Celular/imunologia , Células Cultivadas , Citocinas/genética , Citocinas/imunologia , Inativação Gênica/fisiologia , Humanos , Músculo Liso Vascular/imunologia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/imunologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/imunologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/imunologia , RNA Interferente Pequeno/farmacologia , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/imunologia , Remodelação Vascular/genética , Remodelação Vascular/imunologiaRESUMO
Objective: MicroRNAs have been revealed to be involved in the development of atherosclerosis. The present study is aimed at exploring the potential of miR-99a-5p as a therapy for atherosclerosis. We suspected that miR-99a-5p might inhibit NLRP3 inflammasome activation and promote macrophage autophagy via constraining mTOR, therefore, alleviating atherosclerosis. Methods: The cell viability in ox-LDL-induced THP-1 macrophages was assessed by CCK-8 assay. Bioinformatic analysis was used to predict the target genes of miR-99a-5p. The binding between miR-99a-5p and mTOR was confirmed by luciferase reporter assay. In vivo, a high-fat-diet-induced atherosclerosis model was established in apolipoprotein E knockout mice. Hematoxylin-eosin, oil red O, and Sirius red staining were performed for the determination of atherosclerotic lesions. MTOR and associated protein levels were detected by Western blot analysis. Results: miR-99a-5p inhibited NLRP3 inflammasome activation and promoted macrophage autophagy by targeting mTOR. Enforced miR-99a-5p significantly reduced the levels of inflammasome complex and inflammatory cytokines. Furthermore, miR-99a-5p overexpression inhibited the expression of mTOR, whereas mTOR overexpression reversed the trend of the above behaviors. In vivo, the specific overexpression of miR-99a-5p significantly reduced atherosclerotic lesions, accompanied by a significant downregulation of autophagy marker CD68 protein expression. Conclusion: We demonstrated for the first time that miR-99a-5p may be considered a therapy for atherosclerosis. The present study has revealed that miR-99a-5p might inhibit NLRP3 inflammasome activation and promote macrophage autophagy by targeting mTOR, therefore, alleviating atherosclerosis.
Assuntos
Aterosclerose , MicroRNAs , Proteína 3 que Contém Domínio de Pirina da Família NLR , Serina-Treonina Quinases TOR , Animais , Aterosclerose/genética , Aterosclerose/imunologia , Aterosclerose/terapia , Autofagia , Inflamassomos/genética , Inflamassomos/imunologia , Lipoproteínas LDL , Macrófagos/imunologia , Camundongos , MicroRNAs/genética , MicroRNAs/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/imunologiaRESUMO
Understanding maternal immune tolerance is crucial for the development of therapeutics for immunological pregnancy complications. Decidual regulatory T cells (Tregs) play a pivotal role in the maintenance of maternal immune tolerance. Using a murine allogeneic pregnancy model in the current study, we identified the up-regulation of gonadotropin-releasing hormone receptor (GnRHR) in decidual T cell subsets including CD4+ conventional T cells, CD8+ T cells, and CD4+Foxp3+ Tregs. Using a lentivirus-mediated GnRHR overexpression system and a GnRHR agonist, we found that GnRHR activation decreased the expression of Treg functional molecules such as IL10 (IL-10), IL-35 subunit EBI3 (Ebi3), IL2RA (CD25), TNFRSF18 (GITR), ICOS, and Treg master regulator FOXP3. The functional analysis indicated that GnRHR activation impairs the ability of Tregs to inhibit conventional T cell proliferation. We also revealed that GnRHR activation suppressed the mechanistic target of rapamycin (mTOR) signaling in GnRHR-overexpressing splenic Tregs (Wild type C57BL/6 J background) and decidual Tregs. MHY1485, a potent mTOR activator, effectively abolished the effect of the GnRHR agonist and promoted the immunosuppressive capability of Tregs. Furthermore, in an adoptive transfer model, Treg-specific GnRHR knockdown increased Foxp3 expression in decidual Tregs while decreasing the production of IFN-γ and IL-17 in decidual effector CD4+ T cells and reducing the production of IFN-γ in decidual effector CD8+ T cells. Taken together, the present study unveils a novel mechanism by which the immunosuppressive function of decidual Tregs is modulated, and deepens our understanding of maternal immune tolerance.
Assuntos
Tolerância Imunológica , Gravidez , Receptores LHRH , Linfócitos T Reguladores , Serina-Treonina Quinases TOR , Animais , Linfócitos T CD8-Positivos/imunologia , Feminino , Fatores de Transcrição Forkhead/imunologia , Tolerância Imunológica/imunologia , Camundongos , Gravidez/imunologia , Receptores LHRH/imunologia , Linfócitos T Reguladores/imunologia , Serina-Treonina Quinases TOR/imunologiaRESUMO
The use of chimeric antigen receptor (CAR)-engineered regulatory T cells (Tregs) has emerged as a promising strategy to promote immune tolerance. However, in conventional T cells (Tconvs), CAR expression is often associated with tonic signaling, which can induce CAR-T cell dysfunction. The extent and effects of CAR tonic signaling vary greatly according to the expression intensity and intrinsic properties of the CAR. Here, we show that the 4-1BB CSD-associated tonic signal yields a more dramatic effect in CAR-Tregs than in CAR-Tconvs with respect to activation and proliferation. Compared to CD28 CAR-Tregs, 4-1BB CAR-Tregs exhibit decreased lineage stability and reduced in vivo suppressive capacities. Transient exposure of 4-1BB CAR-Tregs to a Treg stabilizing cocktail, including an mTOR inhibitor and vitamin C, during ex vivo expansion sharply improves their in vivo function and expansion after adoptive transfer. This study demonstrates that the negative effects of 4-1BB tonic signaling in Tregs can be mitigated by transient mTOR inhibition.
Assuntos
Receptores de Antígenos Quiméricos/imunologia , Transdução de Sinais/imunologia , Linfócitos T Reguladores/imunologia , Serina-Treonina Quinases TOR/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Animais , Antígenos CD28/imunologia , Antígenos CD28/metabolismo , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/terapia , Antígeno HLA-A2/imunologia , Antígeno HLA-A2/metabolismo , Humanos , Imunossupressores/farmacologia , Imunoterapia Adotiva/métodos , Células Jurkat , Masculino , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Receptores de Antígenos Quiméricos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Transplante Heterólogo , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismoRESUMO
Monocytic-lineage inflammatory Ly6c+CD103+ dendritic cells (DCs) promote antitumor immunity, but these DCs are infrequent in tumors, even upon chemotherapy. Here, we examined how targeting pathways that inhibit the differentiation of inflammatory myeloid cells affect antitumor immunity. Pharmacologic inhibition of Bruton's tyrosine kinase (BTK) and the tryptophan-degrading enzyme indoleamine 2,3-dioxygenase (IDO) or deletion of Btk or Ido1 allowed robust differentiation of inflammatory Ly6c+CD103+ DCs during chemotherapy, promoting antitumor T cell responses and inhibiting tumor growth. Immature Ly6c+c-kit+ precursor cells had epigenetic profiles similar to conventional DC precursors; deletion of Btk or Ido1 promoted differentiation of these cells. Mechanistically, a BTK-IDO axis inhibited a tryptophan-sensitive differentiation pathway driven by GATOR2 and mTORC1, and disruption of the GATOR2 in monocyte-lineage precursors prevented differentiation into inflammatory DCs in vivo. IDO-expressing DCs and monocytic cells were present across a range of human tumors. Thus, a BTK-IDO axis represses differentiation of inflammatory DCs during chemotherapy, with implications for targeted therapies.
Assuntos
Diferenciação Celular/imunologia , Células Dendríticas/imunologia , Neoplasias/imunologia , Linfócitos T/imunologia , Tirosina Quinase da Agamaglobulinemia/imunologia , Tirosina Quinase da Agamaglobulinemia/metabolismo , Animais , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Feminino , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/imunologia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Masculino , Camundongos , Monócitos/citologia , Monócitos/imunologia , Monócitos/metabolismo , Transdução de Sinais/imunologia , Linfócitos T/metabolismo , Serina-Treonina Quinases TOR/imunologia , Serina-Treonina Quinases TOR/metabolismoRESUMO
The COVID-19 pandemic caused by the coronavirus SARS-CoV-2 has become a serious challenge for medicine and science. Analysis of the molecular mechanisms associated with the clinical manifestations and severity of COVID-19 has identified several key points of immune dysregulation observed in SARS-CoV-2 infection. For diabetic patients, factors including higher binding affinity and virus penetration, decreased virus clearance and decreased T cell function, increased susceptibility to hyperinflammation, and cytokine storm may make these patients susceptible to a more severe course of COVID-19 disease. Metabolic changes induced by diabetes, especially hyperglycemia, can directly affect the immunometabolism of lymphocytes in part by affecting the activity of the mTOR protein kinase signaling pathway. High mTOR activity can enhance the progression of diabetes due to the activation of effector proinflammatory subpopulations of lymphocytes and, conversely, low activity promotes the differentiation of T-regulatory cells. Interestingly, metformin, an extensively used antidiabetic drug, inhibits mTOR by affecting the activity of AMPK. Therefore, activation of AMPK and/or inhibition of the mTOR-mediated signaling pathway may be an important new target for drug therapy in COVID-19 cases mostly by reducing the level of pro-inflammatory signaling and cytokine storm. These suggestions have been partially confirmed by several retrospective analyzes of patients with diabetes mellitus hospitalized for severe COVID-19.
Assuntos
Tratamento Farmacológico da COVID-19 , Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Imunidade Celular/efeitos dos fármacos , Metformina/uso terapêutico , Índice de Gravidade de Doença , COVID-19/epidemiologia , COVID-19/imunologia , COVID-19/metabolismo , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/imunologia , Diabetes Mellitus/metabolismo , Humanos , Hipoglicemiantes/farmacologia , Imunidade Celular/fisiologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Linfócitos/metabolismo , Metformina/farmacologia , Mortalidade/tendências , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/imunologia , Serina-Treonina Quinases TOR/metabolismoRESUMO
Immune cells are important constituents of the tumor microenvironment and essential in eradicating tumor cells during conventional therapies or novel immunotherapies. The mechanistic target of rapamycin (mTOR) signaling pathway senses the intra- and extracellular nutrient status, growth factor supply, and cell stress-related changes to coordinate cellular metabolism and activation dictating effector and memory functions in mainly all hematopoietic immune cells. In addition, the mTOR complex 1 (mTORC1) and mTORC2 are frequently deregulated and become activated in cancer cells to drive cell transformation, survival, neovascularization, and invasion. In this review, we provide an overview of the influence of mTOR complexes on immune and cancer cell function and metabolism. We discuss how mTOR inhibitors aiming to target cancer cells will influence immunometabolic cell functions participating either in antitumor responses or favoring tumor cell progression in individual immune cells. We suggest immunometabolism as the weak spot of anticancer therapy and propose to evaluate patients according to their predominant immune cell subtype in the cancer tissue. Advances in metabolic drug development that hold promise for more effective treatments in different types of cancer will have to consider their effects on the immune system.
Assuntos
Antineoplásicos/uso terapêutico , Desenvolvimento de Medicamentos , Proteínas de Neoplasias , Transdução de Sinais , Serina-Treonina Quinases TOR , Animais , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/imunologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas de Neoplasias/imunologia , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Neoplasias/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Serina-Treonina Quinases TOR/imunologia , Serina-Treonina Quinases TOR/metabolismoRESUMO
IFN-γ, a proinflammatory cytokine produced primarily by T cells and NK cells, activates macrophages and engages mechanisms to control pathogens. Although there is evidence of IFN-γ production by murine macrophages, IFN-γ production by normal human macrophages and their subsets remains unknown. Herein, we show that human M1 macrophages generated by IFN-γ and IL-12- and IL-18-stimulated monocyte-derived macrophages (M0) produce significant levels of IFN-γ. Further stimulation of IL-12/IL-18-primed macrophages or M1 macrophages with agonists for TLR-2, TLR-3, or TLR-4 significantly enhanced IFN-γ production in contrast to the similarly stimulated M0, M2a, M2b, and M2c macrophages. Similarly, M1 macrophages generated from COVID-19-infected patients' macrophages produced IFN-γ that was enhanced following LPS stimulation. The inhibition of M1 differentiation by Jak inhibitors reversed LPS-induced IFN-γ production, suggesting that differentiation with IFN-γ plays a key role in IFN-γ induction. We subsequently investigated the signaling pathway(s) responsible for TLR-4-induced IFN-γ production in M1 macrophages. Our results show that TLR-4-induced IFN-γ production is regulated by the ribosomal protein S6 kinase (p70S6K) through the activation of PI3K, the mammalian target of rapamycin complex 1/2 (mTORC1/2), and the JNK MAPK pathways. These results suggest that M1-derived IFN-γ may play a key role in inflammation that may be augmented following bacterial/viral infections. Moreover, blocking the mTORC1/2, PI3K, and JNK MAPKs in macrophages may be of potential translational significance in preventing macrophage-mediated inflammatory diseases.
Assuntos
Interferon gama/biossíntese , Macrófagos/efeitos dos fármacos , Poli I-C/farmacologia , COVID-19/imunologia , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/imunologia , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/imunologia , Macrófagos/imunologia , Fosfatidilinositol 3-Quinases/imunologia , Proteínas Quinases S6 Ribossômicas 70-kDa/antagonistas & inibidores , Proteínas Quinases S6 Ribossômicas 70-kDa/imunologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/imunologia , Receptor 4 Toll-Like/agonistasRESUMO
Myeloid-derived suppressor cells (MDSC) are induced during active TB disease to restore immune homeostasis but instead exacerbate disease outcome due to chronic inflammation. Autophagy, in conventional phagocytes, ensures successful clearance of M.tb. However, autophagy has been demonstrated to induce prolonged MDSC survival. Here we investigate the relationship between autophagy mediators and MDSC in the context of active TB disease and during anti-TB therapy. We demonstrate a significant increase in MDSC frequencies in untreated active TB cases with these MDSC expressing TLR4 and significantly more mTOR and IL-6 than healthy controls, with mTOR levels decreasing during anti-TB therapy. Finally, we show that HMGB1 serum concentrations decrease in parallel with mTOR. These findings suggest a complex interplay between MDSC and autophagic mediators, potentially dependent on cellular localisation and M.tb infection state.
Assuntos
Autofagia/imunologia , Células Supressoras Mieloides/imunologia , Tuberculose/imunologia , Antituberculosos/uso terapêutico , Autofagia/efeitos dos fármacos , Proteína HMGB1/imunologia , Proteína HMGB1/metabolismo , Humanos , Interleucina-6/imunologia , Interleucina-6/metabolismo , Células Supressoras Mieloides/efeitos dos fármacos , Células Supressoras Mieloides/metabolismo , Serina-Treonina Quinases TOR/imunologia , Serina-Treonina Quinases TOR/metabolismo , Tuberculose/tratamento farmacológico , Tuberculose/metabolismoRESUMO
Immune evasion is a hallmark of persistent echinococcal infection, comprising modulation of innate immune cells and antigen-specific T cell responses. However, recognition of Echinococcus granulosus by dendritic cells (DCs) is a key determinant of the host's response to this parasite. Given that mTOR signaling pathway has been described as a regulator linking metabolism and immune function in DCs, we reported for the first time in these cells, global translation levels, antigen uptake, phenotype, cytokine transcriptional levels, and splenocyte priming activity upon recognition of the hydatid fluid (HF) and the highly glycosylated laminar layer (LL). We found that LL induced a slight up-regulation of CD86 and MHC II in DCs and also stimulated the production of IL-6 and TNF-α. By contrast, HF did not increase the expression of any co-stimulatory molecules, but also down-modulated CD40 and stimulated the expression of the anti-inflammatory cytokine IL-10. Both parasitic antigens promoted protein synthesis through mTOR activation. The use of rapamycin decreased the expression of the cytokines tested, empowered the down-modulation of CD40 and also reduced splenocyte proliferation. Finally, we showed that E. granulosus antigens increase the amounts of LC3-positive structures in DCs which play critical roles in the presentation of these antigens to T cells.
Assuntos
Antígenos de Helmintos/imunologia , Células Dendríticas/imunologia , Equinococose/imunologia , Echinococcus granulosus/imunologia , Transdução de Sinais/imunologia , Serina-Treonina Quinases TOR/imunologia , Animais , Autofagossomos/imunologia , Autofagossomos/metabolismo , Proliferação de Células , Células Cultivadas , Citocinas/genética , Citocinas/imunologia , Citocinas/metabolismo , Células Dendríticas/citologia , Células Dendríticas/parasitologia , Equinococose/parasitologia , Echinococcus granulosus/fisiologia , Feminino , Citometria de Fluxo , Camundongos , Microscopia Confocal , Linfócitos T/imunologia , Serina-Treonina Quinases TOR/metabolismoRESUMO
Respiratory syncytial virus (RSV) infection in early life is associated strongly with the subsequent development and exacerbation of asthma, however, the mechanism is still ambiguous. In this study, we identified that RSV nonstructural protein (NS) 1 plays a critical role. Plasmid-mediated overexpression of NS1 induced significant airway hyperresponsiveness, eosinophilia, and mucus hyperproduction in mice. In the pNS1 group, there were markedly elevated proportions of Th2 and Th17 cells, while Th1 and Foxp3+ regulatory T cells (Tregs) significantly declined compared with the control group. Serum concentrations of interleukin (IL)-4, IL-5, IL-6, IL-17, transforming growth factor-beta, and tumor necrosis factor-alpha increased but levels of interferon-gamma and interleukin-10 declined in pNS1 group. Besides, NS1 caused a significant rise of serum thymic stromal lymphopoietin (TSLP) and OX40L levels, and a neutralizing mAb anti-OX40L was capable of promoting RSV clearance and attenuating the airway allergic inflammation caused by pNS1. Otherwise, OX40L-blocking counteracts the inhibitory effect of pNS1 on Tregs in the spleen. RSV NS1 caused elevated levels of phospho-AKT, phospho-mTOR, and phospho-S6K1, which were partially attenuated by anti-OX40L. Moreover, a specific inhibitor of mTORC1 significantly relieved the inhibition of Foxp3 expression and Tregs differentiation. Together, the data indicate that RSV NS1 protein breaks immune tolerance and induces airway inflammation and hyperresponsiveness in mice. In this process, NS1-stimulated TSLP and OX40L play a major role by inhibiting the induction of Tregs, which is at least partially mediated by modulating AKT-mTOR signaling pathways.
Assuntos
Tolerância Imunológica/imunologia , Infecções por Vírus Respiratório Sincicial/imunologia , Transdução de Sinais/imunologia , Linfócitos T Reguladores/imunologia , Proteínas não Estruturais Virais/imunologia , Animais , Citocinas/imunologia , Regulação para Baixo , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Ligante OX40/imunologia , Receptores OX40/imunologia , Hipersensibilidade Respiratória/imunologia , Hipersensibilidade Respiratória/virologia , Infecções por Vírus Respiratório Sincicial/complicações , Vírus Sincicial Respiratório Humano/imunologia , Serina-Treonina Quinases TOR/imunologia , Linfopoietina do Estroma do TimoRESUMO
Regulatory T (Treg) cells that express forkhead box P3 (Foxp3) are pivotal for immune tolerance. Although inflammatory mediators cause Foxp3 instability and Treg cell dysfunction, their regulatory mechanisms remain incompletely understood. Here, we show that the transfer of Treg cells deficient in the activating immunoreceptor DNAM-1 ameliorated the development of graft-versus-host disease better than did wild-type Treg cells. We found that DNAM-1 competes with T cell immunoreceptor with Ig and ITIM domains (TIGIT) in binding to their common ligand CD155 and therefore regulates TIGIT signaling to down-regulate Treg cell function without DNAM-1-mediated intracellular signaling. DNAM-1 deficiency augments TIGIT signaling; this subsequently inhibits activation of the protein kinase B-mammalian target of rapamycin complex 1 pathway, resulting in the maintenance of Foxp3 expression and Treg cell function under inflammatory conditions. These findings demonstrate that DNAM-1 regulates Treg cell function via TIGIT signaling and thus, it is a potential molecular target for augmenting Treg function in inflammatory diseases.
Assuntos
Antígenos de Diferenciação de Linfócitos T/genética , Fatores de Transcrição Forkhead/genética , Doença Enxerto-Hospedeiro/genética , Receptores Imunológicos/genética , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Animais , Antígenos de Diferenciação de Linfócitos T/imunologia , Fatores de Transcrição Forkhead/imunologia , Regulação da Expressão Gênica , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Humanos , Tolerância Imunológica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/imunologia , Receptores Imunológicos/imunologia , Receptores Virais/genética , Receptores Virais/imunologia , Transdução de Sinais , Linfócitos T Reguladores/patologia , Linfócitos T Reguladores/transplante , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/imunologia , Irradiação Corporal TotalRESUMO
AIMS: Focal cortical dysplasia (FCD) type 2 is an epileptogenic malformation of the neocortex associated with somatic mutations in the mammalian target of rapamycin (mTOR) pathway. Histopathologically, FCD 2 is subdivided into FCD 2a and FCD 2b, the only discriminator being the presence of balloon cells (BCs) in FCD 2b. While pro-epileptogenic immune system activation and inflammatory responses are commonly detected in both subtypes, it is unknown what contextual role BCs play. METHODS: The present study employed RNA sequencing of surgically resected brain tissue from FCD 2a (n = 11) and FCD 2b (n = 20) patients compared to autopsy control (n = 9) focusing on three immune system processes: adaptive immunity, innate immunity and cytokine production. This analysis was followed by immunohistochemistry on a clinically well-characterised FCD 2 cohort. RESULTS: Differential expression analysis revealed stronger expression of components of innate immunity, adaptive immunity and cytokine production in FCD 2b than in FCD 2a, particularly complement activation and antigen presentation. Immunohistochemical analysis confirmed these findings, with strong expression of leukocyte antigen I and II in FCD 2b as compared to FCD 2a. Moreover, T-lymphocyte tissue infiltration was elevated in FCD 2b. Expression of markers of immune system activation in FCD 2b was concentrated in subcortical white matter. Lastly, antigen presentation was strongly correlated with BC load in FCD 2b lesions. CONCLUSION: We conclude that, next to mutation-driven mTOR activation and seizure activity, BCs are crucial drivers of inflammation in FCD 2b. Our findings indicate that therapies targeting inflammation may be beneficial in FCD 2b.
Assuntos
Epilepsia/patologia , Sistema Imunitário/metabolismo , Malformações do Desenvolvimento Cortical do Grupo I/patologia , Malformações do Desenvolvimento Cortical/patologia , Serina-Treonina Quinases TOR/metabolismo , Adolescente , Criança , Epilepsia/genética , Epilepsia/imunologia , Humanos , Masculino , Malformações do Desenvolvimento Cortical/genética , Malformações do Desenvolvimento Cortical/imunologia , Malformações do Desenvolvimento Cortical do Grupo I/genética , Malformações do Desenvolvimento Cortical do Grupo I/imunologia , Pessoa de Meia-Idade , Mutação/genética , Neocórtex/patologia , Neurônios/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/imunologia , Substância Branca/metabolismoRESUMO
Efficient immune responses rely on heterogeneity, which in CD8+ T cells, amongst other mechanisms, is achieved by asymmetric cell division (ACD). Here we find that ageing, known to negatively impact immune responses, impairs ACD in murine CD8+ T cells, and that this phenotype can be rescued by transient mTOR inhibition. Increased ACD rates in mitotic cells from aged mice restore the expansion and memory potential of their cellular progenies. Further characterization of the composition of CD8+ T cells reveals that virtual memory cells (TVM cells), which accumulate during ageing, have a unique proliferation and metabolic profile, and retain their ability to divide asymmetrically, which correlates with increased memory potential. The opposite is observed for naive CD8+ T cells from aged mice. Our data provide evidence on how ACD modulation contributes to long-term survival and function of T cells during ageing, offering new insights into how the immune system adapts to ageing.
Assuntos
Envelhecimento/genética , Divisão Celular Assimétrica/genética , Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/genética , Serina-Treonina Quinases TOR/genética , Envelhecimento/imunologia , Animais , Divisão Celular Assimétrica/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica , Imunidade Inata , Interferon gama/genética , Interferon gama/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Subunidade beta de Receptor de Interleucina-2/genética , Subunidade beta de Receptor de Interleucina-2/imunologia , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Ativação Linfocitária , Camundongos , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Receptores CXCR3/genética , Receptores CXCR3/imunologia , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Receptores de Interleucina-7/genética , Receptores de Interleucina-7/imunologia , Transdução de Sinais , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/imunologiaRESUMO
BACKGROUND: We investigated the effect of the mammalian target of rapamycin (mTOR) pathway on CD8+ T cell immunity through Eomesodermin (Eomes) in intensive care unit (ICU) patients with invasive candidiasis (IC) and in a mouse model. METHODS: We evaluated quantitative changes in parameters of the mTOR/phosphorylated ribosomal S6 kinase (pS6K) pathway and immune system at the onset of infection in ICU patients. The study was registered on 28 February 2017 at chictr.org.cn (ChiCTR-ROC-17010750). We also used a mouse model of Candida infection and constructed T-cell-specific mTOR and T-cell-specific tuberous sclerosis complex (TSC) 1 conditional knockout mice to elucidate the molecular mechanisms. RESULTS: We enrolled 88 patients, including 8 with IC. The IC group had lower CD8+ T cell counts, higher serum levels of mTOR, pS6K, Eomes and interleukin (IL)-6. The mouse model with IC showed results consistent in the clinical study. The CD8+ T cell immune response to IC seemed to be weakened in TSC1 knockout mice compared with wild-type IC mice, demonstrating that mTOR activation resulted in the impaired CD8+ T cell immunity in IC. CONCLUSIONS: In IC, the mTOR activation may play a vital role in impaired CD8+ T cell immunity through enhancing expression of Eomes. The study was registered on 28 February 2017 at chictr.org.cn (identifier ChiCTR-ROC-17010750).
Assuntos
Linfócitos T CD8-Positivos/imunologia , Candidíase Invasiva/imunologia , Transdução de Sinais/imunologia , Proteínas com Domínio T/imunologia , Serina-Treonina Quinases TOR/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Diferenciação Celular , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismoRESUMO
Background: Myeloid-derived suppressor cells (MDSCs) can prevent allograft rejection and induce immune tolerance in transplantation models. Previous studies have demonstrated that inhibition of mTOR signaling can enhance the MDSC protective effect in heart transplantation (HTx) by promoting MDSC expansion. In addition, mTOR inhibition is related to autophagy. The present study investigated the protective mechanism of mTOR-deficient monocytic MDSCs (M-MDSCs) in mouse HTx. Methods: Myeloid-specific mTOR conditional knockout mice were generated to obtain mTOR-/- M-MDSCs. The proliferation and immunosuppressive function of mTOR-/- M-MDSCs were determined by flow cytometry and T cell proliferation assays. The mTOR-/- M-MDSC intracellular autophagy levels were determined using western blotting and electron microscopy. RNAseq analysis was performed for wild-type (WT) and mTOR-/- M-MDSCs. Allogeneic HTx mouse model was established and treated with WT or mTOR-/- M-MDSCs. Enzyme-linked immunosorbent assay, flow cytometry, and immunohistochemistry assays were performed to determine WT and mTOR-/- M-MDSC-induced immune tolerance. Results: The mTOR deficiency promoted M-MDSC differentiation and enhanced intracellular autophagy levels in vivo and in vitro. mTOR deficiency also enhanced the immunosuppressive function of M-MDSCs. In addition, infusing with WT and mTOR-/- M-MDSCs prolonged cardiac allograft survival and established immune tolerance in recipient mice by inhibiting T cell activation and inducing regulatory T cells. Conclusion: mTOR deficiency enhances the immunosuppressive function of M-MDSCs and prolongs mouse cardiac allograft survival.
Assuntos
Diferenciação Celular/imunologia , Transplante de Coração/métodos , Células Supressoras Mieloides/imunologia , Serina-Treonina Quinases TOR/imunologia , Tolerância ao Transplante/imunologia , Aloenxertos/imunologia , Animais , Autofagia/genética , Autofagia/imunologia , Diferenciação Celular/genética , Proliferação de Células , Expressão Gênica/imunologia , Tolerância Imunológica/genética , Tolerância Imunológica/imunologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Células Supressoras Mieloides/metabolismo , Células Supressoras Mieloides/ultraestrutura , Linfócitos T/imunologia , Linfócitos T/metabolismo , Serina-Treonina Quinases TOR/deficiência , Serina-Treonina Quinases TOR/genética , Tolerância ao Transplante/genéticaRESUMO
Mucosal-associated invariant T (MAIT) cells have important functions in immune responses against pathogens and in diseases, but mechanisms controlling MAIT cell development and effector lineage differentiation remain unclear. Here, we report that IL-2/IL-15 receptor ß chain and inducible costimulatory (ICOS) not only serve as lineage-specific markers for IFN-γ-producing MAIT1 and IL-17A-producing MAIT17 cells, but are also important for their differentiation, respectively. Both IL-2 and IL-15 induce mTOR activation, T-bet upregulation, and subsequent MAIT cell, especially MAIT1 cell, expansion. By contrast, IL-1ß induces more MAIT17 than MAIT1 cells, while IL-23 alone promotes MAIT17 cell proliferation and survival, but synergizes with IL-1ß to induce strong MAIT17 cell expansion in an mTOR-dependent manner. Moreover, mTOR is dispensable for early MAIT cell development, yet pivotal for MAIT cell effector differentiation. Our results thus show that mTORC2 integrates signals from ICOS and IL-1ßR/IL-23R to exert a crucial role for MAIT17 differentiation, while the IL-2/IL-15R-mTORC1-T-bet axis ensures MAIT1 differentiation.
Assuntos
Citocinas/imunologia , Proteína Coestimuladora de Linfócitos T Induzíveis/imunologia , Ativação Linfocitária/imunologia , Alvo Mecanístico do Complexo 1 de Rapamicina/imunologia , Alvo Mecanístico do Complexo 2 de Rapamicina/imunologia , Células T Invariantes Associadas à Mucosa/imunologia , Animais , Diferenciação Celular/imunologia , Células Cultivadas , Citocinas/metabolismo , Humanos , Proteína Coestimuladora de Linfócitos T Induzíveis/metabolismo , Interleucina-15/imunologia , Interleucina-15/metabolismo , Interleucina-2/imunologia , Interleucina-2/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Células T Invariantes Associadas à Mucosa/citologia , Células T Invariantes Associadas à Mucosa/metabolismo , Transdução de Sinais/imunologia , Serina-Treonina Quinases TOR/imunologia , Serina-Treonina Quinases TOR/metabolismoRESUMO
Qingfei oral liquid (QF) is a traditional Chinese medicine that has been used to treat patients with viral pneumonia and asthma for decades. Our previous study revealed that QF prevents airway inflammation and reduces airway hyperresponsiveness (AHR) in respiratory syncytial virus (RSV)-infected asthmatic mice. RSV infection can exacerbate asthma in pediatric patients and induce autophagy, which leads to the promotion of inflammatory cytokine production in the pathology of this disease. The effect of QF on regulating autophagy in RSV-infected asthma patients has not been fully elucidated. In this study, we identified compounds of QF by HPLC-DAD-Q-TOF-MS/MS. The RSV infected OVA challenged mice, we evaluated the RSV-infected asthma model. We found that treatment with QF alleviated airway inflammation and mitigated airway AHR in RSV-infected asthmatic mice. In addition, we found that QF inhibited autophagosome formation and the expression of LC3 protein by using electron and laser confocal microscopy, respectively, to assess RSV-infected asthmatic mice lung tissues. Furthermore, QF was found to reduce the quantity of autophagy and its related proteins LC3B (light chain 3B), Beclin-1, p62 and Atg5 (autophagy-related gene 5) and downstream inflammatory cytokines TNF-α, IL-4, IL-6, and IL-13 via an action in mTOR-dependent signaling in vivo and in vitro. These findings suggest that QF can alleviate the inflammation caused by RSV infection in asthmatic mice, and its mechanism may be involved in the regulation of autophagy via the mTOR signaling pathway.