RESUMO
Compelling experimental evidence links immunity and metabolism. In this perspective, we propose forkhead-box-P3 (FoxP3)+CD4+CD25+ regulatory T (Treg) cells as key metabolic sensors controlling the immunological state in response to their intrinsic capacity to perceive nutritional changes. Treg cell high anabolic state in vivo, residency in metabolically crucial districts, and recirculation between lymphoid and non-lymphoid sites enable them to recognize the metabolic cues and adapt their intracellular metabolism and anti-inflammatory function at the paracrine and systemic levels. As privileged regulators at the interface between neuroendocrine and immune systems, the role of Treg cells in maintaining metabolic homeostasis makes these cells promising targets of therapeutic strategies aimed at restoring organismal homeostasis not only in autoimmune but also metabolic disorders.
Assuntos
Fatores de Transcrição Forkhead , Linfócitos T Reguladores , Fatores de Transcrição Forkhead/metabolismo , Subunidade alfa de Receptor de Interleucina-2 , Imunoterapia , HomeostaseRESUMO
Human CD4+CD25hiFOXP3+ regulatory T (Treg) cells are key players in the control of immunological self-tolerance and homeostasis. Here, we report that signals of pseudo-starvation reversed human Treg cell in vitro anergy through an integrated transcriptional response, pertaining to proliferation, metabolism, and transmembrane solute carrier transport. At the molecular level, the Treg cell proliferative response was dependent on the induction of the cystine/glutamate antiporter solute carrier (SLC)7A11, whose expression was controlled by the nuclear factor erythroid 2-related factor 2 (NRF2). SLC7A11 induction in Treg cells was impaired in subjects with relapsing-remitting multiple sclerosis (RRMS), an autoimmune disorder associated with reduced Treg cell proliferative capacity. Treatment of RRMS subjects with dimethyl fumarate (DMF) rescued SLC7A11 induction and fully recovered Treg cell expansion. These results suggest a previously unrecognized mechanism that may account for the progressive loss of Treg cells in autoimmunity and unveil SLC7A11 as major target for the rescue of Treg cell proliferation.
Assuntos
Sistema y+ de Transporte de Aminoácidos/imunologia , Proliferação de Células/fisiologia , Linfócitos T Reguladores/imunologia , Adulto , Autoimunidade/imunologia , Células Cultivadas , Feminino , Homeostase/imunologia , Humanos , Tolerância Imunológica/imunologia , Masculino , Esclerose Múltipla Recidivante-Remitente/imunologia , Fator 2 Relacionado a NF-E2/imunologiaRESUMO
Immunometabolism has been demonstrated to control immune tolerance and the pathogenic events leading to autoimmunity. Compelling experimental evidence also suggests that intracellular metabolic programs influence differentiation, phenotype, proliferation, and effector functions of anti-inflammatory CD4+CD25+Foxp3+ regulatory T (Treg) cells. Indeed, alterations in intracellular metabolism associate with quantitative and qualitative impairments of Treg cells in several pathological conditions. In this review, we summarize the most recent advances linking how metabolic pathways control Treg cell homeostasis and their alterations occurring in autoimmunity. Also, we analyze how metabolic manipulations could be employed to restore Treg cell frequency and function with the aim to create novel therapeutic opportunities to halt immune-mediated disorders.
Assuntos
Autoimunidade , Linfócitos T Reguladores , Linfócitos T Reguladores/imunologia , Humanos , Autoimunidade/imunologia , Animais , Homeostase/imunologia , Tolerância Imunológica/imunologia , Doenças Autoimunes/imunologia , Diferenciação Celular/imunologia , Plasticidade Celular/imunologiaRESUMO
AIMS/HYPOTHESIS: Type 1 diabetes is an autoimmune disorder that is characterised by destruction of pancreatic beta cells by autoreactive T lymphocytes. Although islet autoantibodies (AAb) are an indicator of disease progression, specific immune biomarkers that can be used as target molecules to halt development of type 1 diabetes have not been discovered. Soluble immune checkpoint molecules (sICM) play a pivotal role in counteracting excessive lymphocyte responses, but their role in type 1 diabetes is unexplored. In this longitudinal study, we measured sICM levels in AAb-positive (AAb+) children to identify molecules related to type 1 diabetes progression. METHODS: We measured the levels of 14 sICM in the sera of AAb+ children (n=57) compared to those with recent-onset type 1 diabetes (n=79) and healthy children (n=44), obtained from two cohorts. AAb+ children were followed up and divided based on their progression to type 1 diabetes (AAbP) or not (AAbNP) (if they lost islet autoimmunity and did not develop disease in subsequent years). sICM were also measured in the sample taken at the visit closest to disease onset in AAbP children. RESULTS: We found that AAb+ children had a distinct sICM profile compared with healthy children and those with recent-onset type 1 diabetes. In addition, AAb+ children who progressed to type 1 diabetes (AAbP) had higher sICM concentrations than non-progressors (AAbNP). Further, sICM levels decreased in AAbP children close to disease onset. Application of Cox regression models highlighted that high concentrations of soluble programmed cell death protein 1 (sPD-1) are associated with type 1 diabetes progression (HR 1.71; 95% CI 1.16, 2.51; p=0.007). CONCLUSIONS/INTERPRETATION: This study reveals an sICM profile that is dysregulated during the preclinical stage of type 1 diabetes, and identifies sPD-1 as a pathophysiologically-relevant molecule that is associated with disease progression, offering a potential target for early interventions in autoimmune diabetes.
Assuntos
Diabetes Mellitus Tipo 1 , Criança , Humanos , Autoanticorpos , Estudos Longitudinais , Receptor de Morte Celular Programada 1 , Progressão da DoençaRESUMO
BACKGROUND: Calorie restriction (CR) ameliorates preclinical models of multiple sclerosis (MS) via multiple mechanisms. These include decreased leptin, a proinflammatory adipokine, but mechanistic studies in humans are lacking. Tests of daily and intermittent CR (iCR) in people with MS (pwMS) showed improvements in fatigue and well-being measures. This trial studied the effects of 12-week iCR on metabolic, immunological, and clinical outcomes in pwMS. METHOD: Relapsing-remitting MS participants were randomised to iCR or a control group. Study visits were conducted at baseline, 6 and 12 weeks. The primary outcome was reduction in serum leptin levels at 12 weeks. Feasibility and safety were assessed by diet adherence and adverse events (AEs). Secondary outcomes included changes in anthropometric and body composition measures, metabolic and immunologic profiling, and clinical measures. Mixed effects linear regression models were used to evaluate outcome differences between and within groups over time. RESULTS: Forty-two pwMS were randomised, 34 completed the study (17/group). Leptin serum levels at 12 weeks were significantly lower in the iCR versus the control group (mean decrease -6.98 µg/dL, 95% CI: -28.02 to 14.06; p=0.03). Adherence to iCR was 99.5% and 97.2% at 6 and 12 weeks, respectively, and no serious AEs were reported. An increase in blood CD45RO+ regulatory T-cell numbers was seen after 6 weeks of iCR. Exploratory cognitive testing demonstrated a significant improvement in the Symbol Digit Modality Test Score in the iCR group at 12 weeks. CONCLUSIONS: iCR has the potential to benefit metabolic and immunologic profiles and is safe and feasible in pwMS. TRIAL REGISTRATION NUMBER: NCT03539094 .
RESUMO
AIMS/HYPOTHESIS: We assessed the levels of blood circulating immune checkpoint molecules (ICMs) at diagnosis of type 1 diabetes, and determined their association with the risk of developing an additional autoimmune disorder over time. METHODS: Children with new-onset type 1 diabetes (n = 143), without biological and/or clinical signs of additional autoimmune disorders, and healthy children (n = 75) were enrolled, and blood circulating levels of 14 ICMs were measured. The children with type 1 diabetes were divided into two groups on the basis of the development of an additional autoimmune disease in the 5 years after diabetes onset. Differences in soluble ICM levels between the groups were assessed, and a Cox regression analysis was used to evaluate their association with the risk of development of an additional autoimmune disease over time. To validate the data, circulating ICMs were measured in an independent cohort of 60 children with new-onset type 1 diabetes stratified into two groups. RESULTS: We found that the levels of circulating ICMs were significantly higher in children with new-onset diabetes compared with healthy children. Further, we observed that children with type 1 diabetes who developed a second autoimmune disease over time (T1D-AAD+ children) had higher levels of soluble ICMs than children with type 1 diabetes who did not (T1D-AAD- children). Cox regression models revealed that high circulating levels of CD137/4-1BB and PD-1 molecules at diabetes diagnosis were associated with the risk of developing an additional autoimmune disease in both type 1 diabetes cohorts. CONCLUSIONS/INTERPRETATION: Our findings suggest that soluble CD137/4-1BB and PD-1 molecules may be used as prognostic biomarkers in children with type 1 diabetes, and may pave the way for novel immunological screening at diabetes onset, allowing early identification of children at higher risk of developing other autoimmune conditions over time.
Assuntos
Doenças Autoimunes , Diabetes Mellitus Tipo 1 , Criança , Estudos de Coortes , Humanos , Proteínas de Checkpoint Imunológico , Receptor de Morte Celular Programada 1RESUMO
Nutrition affects all physiological processes occurring in our body, including those related to the function of the immune system; indeed, metabolism has been closely associated with the differentiation and activity of both innate and adaptive immune cells. While excessive energy intake and adiposity have been demonstrated to cause systemic inflammation, several clinical and experimental evidence show that calorie restriction (CR), not leading to malnutrition, is able to delay aging and exert potent anti-inflammatory effects in different pathological conditions. This review provides an overview of the ability of different CR-related nutritional strategies to control autoimmune, cardiovascular, and infectious diseases, as tested by preclinical studies and human clinical trials, with a specific focus on the immunological aspects of these interventions. In particular, we recapitulate the state of the art on the cellular and molecular mechanisms pertaining to immune cell metabolic rewiring, regulatory T cell expansion, and gut microbiota composition, which possibly underline the beneficial effects of CR. Although studies are still needed to fully evaluate the feasibility and efficacy of the nutritional intervention in clinical practice, the experimental observations discussed here suggest a relevant role of CR in lowering the inflammatory state in a plethora of different pathologies, thus representing a promising therapeutic strategy for the control of human health.
Assuntos
Restrição Calórica , Obesidade , Humanos , Obesidade/terapia , Adiposidade , Estado Nutricional , Envelhecimento/metabolismoRESUMO
BACKGROUND AND OBJECTIVES: The role of B cells in the pathogenic events leading to relapsing multiple sclerosis (R-MS) has only been recently elucidated. A pivotal step in defining this role has been provided by therapeutic efficacy of anti-CD20 monoclonal antibodies. Indeed, treatment with anti-CD20 can also alter number and function of other immune cells not directly expressing CD20 on their cell surface, whose activities can contribute to unknown aspects influencing therapeutic efficacy. We examined the phenotype and function of cytotoxic lymphocytes and Epstein-Barr virus (EBV)-specific immune responses in people with R-MS before and after ocrelizumab treatment. METHODS: In this prospective study, we collected blood samples from people with R-MS (n = 41) before and 6 and 12 months after initiating ocrelizumab to assess the immune phenotype and the indirect impact on cytotoxic functions of CD8+ T and NK cells. In addition, we evaluated the specific anti-EBV proliferative responses of both CD8+ T and NK lymphocytes as surrogate markers of anti-EBV activity. RESULTS: We observed that while ocrelizumab depleted circulating B cells, it also reduced the expression of activation and migratory markers on both CD8+ T and NK cells as well as their in vitro cytotoxic activity. A comparable pattern in the modulation of immune molecules by ocrelizumab was observed in cytotoxic cells even when patients with R-MS were divided into groups based on their prior disease-modifying treatment. These effects were accompanied by a significant and selective reduction of CD8+ T-cell proliferation in response to EBV antigenic peptides. DISCUSSION: Taken together, our findings suggest that ocrelizumab-while depleting B cells-affects the cytotoxic function of CD8+ and NK cells, whose reduced cross-activity against myelin antigens might also contribute to its therapeutic efficacy during MS.
Assuntos
Anticorpos Monoclonais Humanizados , Linfócitos T CD8-Positivos , Herpesvirus Humano 4 , Fatores Imunológicos , Humanos , Anticorpos Monoclonais Humanizados/farmacologia , Feminino , Adulto , Masculino , Herpesvirus Humano 4/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Pessoa de Meia-Idade , Fatores Imunológicos/farmacologia , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/imunologia , Esclerose Múltipla Recidivante-Remitente/sangue , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Estudos Prospectivos , Proliferação de Células/efeitos dos fármacos , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Ativação Linfocitária/efeitos dos fármacosRESUMO
The molecular mechanisms that govern differential T cell development from CD4+CD25-conventional T (Tconv) into CD4+CD25+ forkhead-box-P3+ (FoxP3+) inducible regulatory T (iTreg) cells remain unclear. Herein, we investigated the relative contribution of protein kinase A (PKA) in this process. Mechanistically, we found that PKA controlled the efficiency of human iTreg cell generation through the expression of different FoxP3 splicing variants containing or not the exon 2. We found that transient PKA inhibition reduced the recruitment of cAMP-responsive element-binding protein (CREB) on regulatory regions of the FoxP3 gene, a condition that is associated with an impaired acquisition of their suppressive capacity in vitro. To corroborate our findings in a human model of autoimmunity, we measured CREB phosphorylation and FoxP3 levels in iTreg cells from treatment-naïve relapsing-remitting (RR)-multiple sclerosis (MS) subjects. Interestingly, both phospho-CREB and FoxP3 induction directly correlated and were significantly reduced in RR-MS patients, suggesting a previously unknown mechanism involved in the induction and function of human iTreg cells.
Assuntos
Autoimunidade , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Proteínas Quinases Dependentes de AMP Cíclico , Fatores de Transcrição Forkhead , Linfócitos T Reguladores , Humanos , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Fosforilação , Regulação da Expressão Gênica , Esclerose Múltipla/imunologia , Esclerose Múltipla/metabolismo , Feminino , MasculinoRESUMO
There is a strong relationship between metabolic state and susceptibility to Mycobacterium tuberculosis (MTB) infection, with energy metabolism setting the basis for an exaggerated immuno-inflammatory response, which concurs with MTB pathogenesis. Herein, we show that controlled caloric restriction (CR), not leading to malnutrition, protects susceptible DBA/2 mice against pulmonary MTB infection by reducing bacterial load, lung immunopathology, and generation of foam cells, an MTB reservoir in lung granulomas. Mechanistically, CR induced a metabolic shift toward glycolysis, and decreased both fatty acid oxidation and mTOR activity associated with induction of autophagy in immune cells. An integrated multi-omics approach revealed a specific CR-induced metabolomic, transcriptomic, and proteomic signature leading to reduced lung damage and protective remodeling of lung interstitial tightness able to limit MTB spreading. Our data propose CR as a feasible immunometabolic manipulation to control MTB infection, and this approach offers an unexpected strategy to boost immunity against MTB.
Assuntos
Tuberculose/prevenção & controle , Animais , Restrição Calórica , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/metabolismo , Tuberculose/imunologia , Tuberculose/metabolismoRESUMO
Mulibrey (muscle-liver-brain-eye) syndrome (MUL) is an autosomal recessive disorder caused by mutations in the TRIpartite motif (TRIM)37 gene, encoding for TRIM37 a member of the TRIM E3 ubiquitin ligase protein family. MUL patients are characterized by growth retardation, dysmorphic features, and a wide range of abnormalities affecting different organs. However, T-cell abnormalities have not been observed in MUL subjects, to date. Here we described the immunological features of a MUL child carrying recently identified TRIM37 mutations, a 17q22 deletion of maternal origin combined with a TRIM37 variant of paternal origin. Here we found quantitative and functional defects in CD4+ T cells from this MUL case. Low levels of TRIM37 protein were specifically detected in CD4+ T cells of MUL patient and associated with their altered proliferation and cytokine production. Of note, both CD4+ and CD8+ T lymphocytes of MUL child displayed an effector memory phenotype compared with healthy children. This clinical case research highlighted the possible role of TRIM37 in the control of immune cell number and function, especially in CD4+ T cells. Finally, this study may contribute to the novel mechanistic studies aim of identifying, in depth, the role of the TRIM37 protein in the immune system.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Nanismo de Mulibrey/genética , Mutação , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/genética , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células , Células Cultivadas , Criança , Citocinas/metabolismo , Predisposição Genética para Doença , Hereditariedade , Humanos , Memória Imunológica , Ativação Linfocitária , Masculino , Nanismo de Mulibrey/diagnóstico , Nanismo de Mulibrey/imunologia , Nanismo de Mulibrey/metabolismo , Linhagem , FenótipoRESUMO
Macrophages are pivotal effector cells in immune responses and tissue remodeling by producing a wide spectrum of mediators, including angiogenic and lymphangiogenic factors. Activation of cannabinoid receptor types 1 and 2 has been suggested as a new strategy to modulate angiogenesis in vitro and in vivo. We investigated whether human lung-resident macrophages express a complete endocannabinoid system by assessing their production of endocannabinoids and expression of cannabinoid receptors. Unstimulated human lung macrophage produce 2-arachidonoylglycerol,N-arachidonoyl-ethanolamine,N-palmitoyl-ethanolamine, and N-oleoyl-ethanolamine. On LPS stimulation, human lung macrophages selectively synthesize 2-arachidonoylglycerol in a calcium-dependent manner. Human lung macrophages express cannabinoid receptor types 1 and 2, and their activation induces ERK1/2 phosphorylation and reactive oxygen species generation. Cannabinoid receptor activation by the specific synthetic agonists ACEA and JWH-133 (but not the endogenous agonist 2-arachidonoylglycerol) markedly inhibits LPS-induced production of vascular endothelial growth factor-A, vascular endothelial growth factor-C, and angiopoietins and modestly affects IL-6 secretion. No significant modulation of TNF-α or IL-8/CXCL8 release was observed. The production of vascular endothelial growth factor-A by human monocyte-derived macrophages is not modulated by activation of cannabinoid receptor types 1 and 2. Given the prominent role of macrophage-assisted vascular remodeling in many tumors, we identified the expression of cannabinoid receptors in lung cancer-associated macrophages. Our results demonstrate that cannabinoid receptor activation selectively inhibits the release of angiogenic and lymphangiogenic factors from human lung macrophage but not from monocyte-derived macrophages. Activation of cannabinoid receptors on tissue-resident macrophages might be a novel strategy to modulate macrophage-assisted vascular remodeling in cancer and chronic inflammation.
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Regulação da Expressão Gênica , Interleucina-6/biossíntese , Macrófagos/metabolismo , Receptor CB1 de Canabinoide/biossíntese , Receptor CB2 de Canabinoide/biossíntese , Fator A de Crescimento do Endotélio Vascular/biossíntese , Fator C de Crescimento do Endotélio Vascular/biossíntese , Canabinoides/farmacologia , Feminino , Humanos , Lipopolissacarídeos/farmacologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , MasculinoRESUMO
TNFR-associated periodic syndrome is an autoinflammatory disorder caused by autosomal-dominant mutations in TNFRSF1A, the gene encoding for TNFR superfamily 1A. The lack of knowledge in the field of TNFR-associated periodic syndrome biology is clear, particularly in the context of control of immune self-tolerance. We investigated how TNF-α/TNFR superfamily 1A signaling can affect T cell biology, focusing on conventional CD4(+)CD25(-) and regulatory CD4(+)CD25(+) T cell functions in patients with TNFR-associated periodic syndrome carrying either high or low penetrance TNFRSF1A mutations. Specifically, we observed that in high penetrance TNFR-associated periodic syndrome, at the molecular level, these alterations were secondary to a hyperactivation of the ERK1/2, STAT1/3/5, mammalian target of rapamycin, and NF-κB pathways in conventional T cells. In addition, these patients had a lower frequency of peripheral regulatory T cells, which also displayed a defective suppressive phenotype. These alterations were partially found in low penetrance TNFR-associated periodic syndrome, suggesting a specific link between the penetrance of the TNFRSF1A mutation and the observed T cell phenotype. Taken together, our data envision a novel role for adaptive immunity in the pathogenesis of TNFR-associated periodic syndrome involving both CD4(+) conventional T cells and Tregs, suggesting a novel mechanism of inflammation in the context of autoinflammatory disorders.
Assuntos
Febre/genética , Febre/imunologia , Doenças Hereditárias Autoinflamatórias/genética , Doenças Hereditárias Autoinflamatórias/imunologia , Mutação/genética , Penetrância , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Linfócitos T Reguladores/imunologia , Adolescente , Adulto , Idoso , Proliferação de Células , Criança , Citocinas/metabolismo , Demografia , Feminino , Febre/patologia , Doenças Hereditárias Autoinflamatórias/patologia , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T/metabolismo , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Adulto JovemRESUMO
Monocytes are major effector cells of innate immunity and recognize several endogenous and exogenous molecules due to the expression of wide spectrum of receptors. Among them, the MHC class I-like molecule CD1d interacts with glycolipids and presents them to iNKT cells, mediating their activation. Simplexide belongs to a novel class of glycolipids isolated from marine sponges and is structurally distinct from other immunologically active glycolipids. In this study we have examined the effects of simplexide on cytokine and chemokine release from human monocytes. Simplexide induces a concentration- and time-dependent release of IL-6, CXCL8, TNF-α and IL-10 and increases the expression of IL6, CXCL8 and IL10 mRNA. Cytokine and chemokine release induced by simplexide from monocytes is dependent on CD1d since: i) a CD1d antagonist, 1,2-bis (diphenylphosphino) ethane [DPPE]-polyethylene glycolmonomethylether [PEG], specifically blocks simplexide-induced activation of monocytes; ii) CD1d knockdown inhibits monocyte activation by simplexide and iii) simplexide induces cytokine production from CD1d-transfected but not parental C1R cell line. Finally, we have shown that simplexide also induces iNKT cell expansion in vitro. Our results demonstrate that simplexide, apart from activating iNKT cells, induces the production of cytokines and chemokines from human monocytes by direct interaction with CD1d.