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1.
Nature ; 610(7932): 555-561, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36171294

RESUMO

CD4+ T cell differentiation requires metabolic reprogramming to fulfil the bioenergetic demands of proliferation and effector function, and enforce specific transcriptional programmes1-3. Mitochondrial membrane dynamics sustains mitochondrial processes4, including respiration and tricarboxylic acid (TCA) cycle metabolism5, but whether mitochondrial membrane remodelling orchestrates CD4+ T cell differentiation remains unclear. Here we show that unlike other CD4+ T cell subsets, T helper 17 (TH17) cells have fused mitochondria with tight cristae. T cell-specific deletion of optic atrophy 1 (OPA1), which regulates inner mitochondrial membrane fusion and cristae morphology6, revealed that TH17 cells require OPA1 for its control of the TCA cycle, rather than respiration. OPA1 deletion amplifies glutamine oxidation, leading to impaired NADH/NAD+ balance and accumulation of TCA cycle metabolites and 2-hydroxyglutarate-a metabolite that influences the epigenetic landscape5,7. Our multi-omics approach revealed that the serine/threonine kinase liver-associated kinase B1 (LKB1) couples mitochondrial function to cytokine expression in TH17 cells by regulating TCA cycle metabolism and transcriptional remodelling. Mitochondrial membrane disruption activates LKB1, which restrains IL-17 expression. LKB1 deletion restores IL-17 expression in TH17 cells with disrupted mitochondrial membranes, rectifying aberrant TCA cycle glutamine flux, balancing NADH/NAD+ and preventing 2-hydroxyglutarate production from the promiscuous activity of the serine biosynthesis enzyme phosphoglycerate dehydrogenase (PHGDH). These findings identify OPA1 as a major determinant of TH17 cell function, and uncover LKB1 as a sensor linking mitochondrial cues to effector programmes in TH17 cells.


Assuntos
Proteínas Quinases Ativadas por AMP , Mitocôndrias , Células Th17 , Glutamina/metabolismo , Interleucina-17/metabolismo , Mitocôndrias/metabolismo , NAD/metabolismo , Fosfoglicerato Desidrogenase/metabolismo , Serina/biossíntese , Serina/metabolismo , Células Th17/citologia , Células Th17/imunologia , Células Th17/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Ciclo do Ácido Cítrico , GTP Fosfo-Hidrolases/deficiência , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo
2.
Proc Natl Acad Sci U S A ; 118(25)2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34161266

RESUMO

Fever can provide a survival advantage during infection. Metabolic processes are sensitive to environmental conditions, but the effect of fever on T cell metabolism is not well characterized. We show that in activated CD8+ T cells, exposure to febrile temperature (39 °C) augmented metabolic activity and T cell effector functions, despite having a limited effect on proliferation or activation marker expression. Transcriptional profiling revealed an up-regulation of mitochondrial pathways, which was consistent with increased mass and metabolism observed in T cells exposed to 39 °C. Through in vitro and in vivo models, we determined that mitochondrial translation is integral to the enhanced metabolic activity and function of CD8+ T cells exposed to febrile temperature. Transiently exposing donor lymphocytes to 39 °C prior to infusion in a myeloid leukemia mouse model conferred enhanced therapeutic efficacy, raising the possibility that exposure of T cells to febrile temperatures could have clinical potential.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Febre/imunologia , Mitocôndrias/metabolismo , Biossíntese de Proteínas , Animais , Antineoplásicos/metabolismo , Linfócitos T CD8-Positivos/ultraestrutura , Citocinas/biossíntese , Glucose/metabolismo , Leucemia Mieloide/imunologia , Leucemia Mieloide/patologia , Leucemia Mieloide/prevenção & controle , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mitocôndrias/ultraestrutura , Modelos Biológicos , Temperatura
3.
Gut ; 72(10): 1971-1984, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37541771

RESUMO

OBJECTIVE: Exhausted T cells with limited effector function are enriched in chronic hepatitis B and C virus (HBV and HCV) infection. Metabolic regulation contributes to exhaustion, but it remains unclear how metabolism relates to different exhaustion states, is impacted by antiviral therapy, and if metabolic checkpoints regulate dysfunction. DESIGN: Metabolic state, exhaustion and transcriptome of virus-specific CD8+ T cells from chronic HBV-infected (n=31) and HCV-infected patients (n=52) were determined ex vivo and during direct-acting antiviral (DAA) therapy. Metabolic flux and metabolic checkpoints were tested in vitro. Intrahepatic virus-specific CD8+ T cells were analysed by scRNA-Seq in a HBV-replicating murine in vivo model of acute and chronic infection. RESULTS: HBV-specific (core18-27, polymerase455-463) and HCV-specific (NS31073-1081, NS31406-1415, NS5B2594-2602) CD8+ T cell responses exhibit heterogeneous metabolic profiles connected to their exhaustion states. The metabolic state was connected to the exhaustion profile rather than the aetiology of infection. Mitochondrial impairment despite intact glucose uptake was prominent in severely exhausted T cells linked to elevated liver inflammation in chronic HCV infection and in HBV polymerase455-463 -specific CD8+ T cell responses. In contrast, relative metabolic fitness was observed in HBeAg-negative HBV infection in HBV core18-27-specific responses. DAA therapy partially improved mitochondrial programmes in severely exhausted HCV-specific T cells and enriched metabolically fit precursors. We identified enolase as a metabolic checkpoint in exhausted T cells. Metabolic bypassing improved glycolysis and T cell effector function. Similarly, enolase deficiency was observed in intrahepatic HBV-specific CD8+ T cells in a murine model of chronic infection. CONCLUSION: Metabolism of HBV-specific and HCV-specific T cells is strongly connected to their exhaustion severity. Our results highlight enolase as metabolic regulator of severely exhausted T cells. They connect differential bioenergetic fitness with distinct exhaustion subtypes and varying liver disease, with implications for therapeutic strategies.


Assuntos
Hepatite B Crônica , Hepatite C Crônica , Hepatite C , Humanos , Animais , Camundongos , Linfócitos T CD8-Positivos/metabolismo , Antivirais/uso terapêutico , Infecção Persistente , Hepatite C Crônica/tratamento farmacológico , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/metabolismo , Hepatite C/tratamento farmacológico , Vírus de Hepatite , Vírus da Hepatite B
4.
Gastroenterology ; 163(4): 965-981.e31, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35738329

RESUMO

BACKGROUND & AIMS: Exhaustion of CD8 T cells has been suggested to inform different clinical outcomes in Crohn's disease, but detailed analyses are lacking. This study aimed to identify the role of exhaustion on a single-cell level and identify relevant CD8 T cell populations in Crohn's disease. METHODS: Blood and intestinal tissue from 58 patients with Crohn's disease (active disease or remission) were assessed for CD8 T cell expression of exhaustion markers and their cytokine profile by highly multiplexed flow and mass cytometry. Key disease-associated subsets were sorted and analyzed by RNA sequencing. CD39 inhibition assays were performed in vitro. RESULTS: Activated CD39+ and CD39+PD-1+ CD8 T cell subsets expressing multiple exhaustion markers were enriched at low frequency in active Crohn's disease. Their cytokine production capacity was inversely linked to the Harvey-Bradshaw Index. Subset-level protein and transcriptome profiling revealed co-existence of effector and exhaustion programs in CD39+ and CD39+ PD-1+CD8 T cells, with CD39+ cells likely originating from the intestine. CD39 enzymatic activity controlled T cell cytokine production. Importantly, transcriptional exhaustion signatures were enriched in remission in CD39-expressing subsets with up-regulation of TOX. Subset-level transcriptomics revealed a CD39-related gene module that is associated with the clinical course. CONCLUSIONS: These data showed a role for the exhaustion of peripheral CD39-expressing CD8 T cell subsets in Crohn's disease. Their low frequency illustrated the utility of single-cell cytometry methods for identification of relevant immune populations. Importantly, the link of their exhaustion status to the clinical activity and their specific gene signatures have implications for exhaustion-based personalized medicine approaches.


Assuntos
Apirase , Linfócitos T CD8-Positivos , Doença de Crohn , Apirase/sangue , Apirase/genética , Apirase/imunologia , Biomarcadores/sangue , Linfócitos T CD8-Positivos/imunologia , Doença de Crohn/sangue , Doença de Crohn/genética , Doença de Crohn/imunologia , Citocinas/imunologia , Humanos , Prognóstico , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Subpopulações de Linfócitos T
5.
BJU Int ; 128(5): 642-651, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34028967

RESUMO

OBJECTIVES: To determine the activity and safety of lutetium-177 (177 Lu)-prostate-specific membrane antigen (PSMA)-617 in men with metastatic castration-resistant prostate cancer (mCRPC) commencing enzalutamide, who are at high risk of early progression, and to identify potential prognostic and predictive biomarkers from imaging, blood and tissue. PARTICIPANTS AND METHODS: ENZA-p (ANZUP 1901) is an open-label, randomized, two-arm, multicentre, phase 2 trial. Participants are randomly assigned (1:1) to treatment with enzalutamide 160 mg daily alone or enzalutamide plus 177 Lu-PSMA-617 7.5 GBq on Days 15 and 57. Two additional 177 Lu-PSMA-617 doses are allowed, informed by Day-92 Gallium-68 (68 Ga)-PSMA positron emission tomography (PET; up to four doses in total). The primary endpoint is prostate-specific antigen (PSA) progression-free survival (PFS). Other major endpoints include radiological PFS, PSA response rate, overall survival, health-related quality of life, adverse events and cost-effectiveness. Key eligibility criteria include: biochemical and/or clinical progression; 68 Ga-PSMA PET-avid disease; no prior androgen signalling inhibitor, excepting abiraterone; no prior chemotherapy for mCRPC; and ≥2 high-risk features for early enzalutamide failure. Assessments are 4 weekly during study treatment, then 6 weekly until radiographic progression. Response Evaluation Criteria in Solid Tumours (RECIST) are used to assess imaging conducted every 12 weeks, 68 Ga-PSMA PET at baseline, Days 15 and 92, and at progression, and 18 F-fluorine deoxyglucose (18 F-FDG) PET at baseline and progression. Translational samples include blood (and optional biopsies) at baseline, Day 92, and first progression. Correlative studies include identification of prognostic and predictive biomarkers from 68 Ga-PSMA and 18 F-FDG PET/CT, circulating tumour cells and circulating tumour DNA. The trial will enrol 160 participants, providing 80% power with a two-sided type-1 error rate of 5% to detect a hazard ratio of 0.625 assuming a median PSA-PFS of 5 months with enzalutamide alone. RESULTS AND CONCLUSION: The combination of 177 Lu-PSMA-617 and enzalutamide may be synergistic. ENZA-p will determine the safety and efficacy of the combination in addition to developing predictive and prognostic biomarkers to better guide treatment decisions.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Glutamato Carboxipeptidase II/antagonistas & inibidores , Neoplasias de Próstata Resistentes à Castração/diagnóstico por imagem , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Antígenos de Superfície , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Benzamidas/administração & dosagem , Ensaios Clínicos Fase II como Assunto , Análise Custo-Benefício , Dipeptídeos/administração & dosagem , Dipeptídeos/efeitos adversos , Dipeptídeos/economia , Fluordesoxiglucose F18 , Isótopos de Gálio , Radioisótopos de Gálio , Compostos Heterocíclicos com 1 Anel/administração & dosagem , Compostos Heterocíclicos com 1 Anel/efeitos adversos , Compostos Heterocíclicos com 1 Anel/economia , Humanos , Lutécio/administração & dosagem , Masculino , Terapia de Alvo Molecular , Estudos Multicêntricos como Assunto , Nitrilas/administração & dosagem , Feniltioidantoína/administração & dosagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Intervalo Livre de Progressão , Antígeno Prostático Específico/administração & dosagem , Antígeno Prostático Específico/efeitos adversos , Antígeno Prostático Específico/sangue , Antígeno Prostático Específico/economia , Neoplasias de Próstata Resistentes à Castração/sangue , Qualidade de Vida , Radioisótopos/administração & dosagem , Compostos Radiofarmacêuticos , Ensaios Clínicos Controlados Aleatórios como Assunto , Critérios de Avaliação de Resposta em Tumores Sólidos , Taxa de Sobrevida
6.
BMC Pregnancy Childbirth ; 21(Suppl 1): 234, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33765951

RESUMO

BACKGROUND: Observation of care at birth is challenging with multiple, rapid and potentially concurrent events occurring for mother, newborn and placenta. Design of electronic data (E-data) collection needs to account for these challenges. The Every Newborn Birth Indicators Research Tracking in Hospitals (EN-BIRTH) was an observational study to assess measurement of indicators for priority maternal and newborn interventions and took place in five hospitals in Bangladesh, Nepal and Tanzania (July 2017-July 2018). E-data tools were required to capture individually-linked, timed observation of care, data extraction from hospital register-records or case-notes, and exit-survey data from women. METHODS: To evaluate this process for EN-BIRTH, we employed a framework organised around five steps for E-data design, data collection and implementation. Using this framework, a mixed methods evaluation synthesised evidence from study documentation, standard operating procedures, stakeholder meetings and design workshops. We undertook focus group discussions with EN-BIRTH researchers to explore experiences from the three different country teams (November-December 2019). Results were organised according to the five a priori steps. RESULTS: In accordance with the five-step framework, we found: 1) Selection of data collection approach and software: user-centred design principles were applied to meet the challenges for observation of rapid, concurrent events around the time of birth with time-stamping. 2) Design of data collection tools and programming: required extensive pilot testing of tools to be user-focused and to include in-built error messages and data quality alerts. 3) Recruitment and training of data collectors: standardised with an interactive training package including pre/post-course assessment. 4) Data collection, quality assurance, and management: real-time quality assessments with a tracking dashboard and double observation/data extraction for a 5% case subset, were incorporated as part of quality assurance. Internet-based synchronisation during data collection posed intermittent challenges. 5) Data management, cleaning and analysis: E-data collection was perceived to improve data quality and reduce time cleaning. CONCLUSIONS: The E-Data system, custom-built for EN-BIRTH, was valued by the site teams, particularly for time-stamped clinical observation of complex multiple simultaneous events at birth, without which the study objectives could not have been met. However before selection of a custom-built E-data tool, the development time, higher training and IT support needs, and connectivity challenges need to be considered against the proposed study or programme's purpose, and currently available E-data tool options.


Assuntos
Registros Eletrônicos de Saúde/organização & administração , Sistemas de Informação Hospitalar/organização & administração , Hospitais/estatística & dados numéricos , Assistência Perinatal/organização & administração , Bangladesh , Confiabilidade dos Dados , Registros Eletrônicos de Saúde/estatística & dados numéricos , Feminino , Grupos Focais , Sistemas de Informação Hospitalar/estatística & dados numéricos , Humanos , Recém-Nascido , Nepal , Assistência Perinatal/estatística & dados numéricos , Gravidez , Software , Inquéritos e Questionários , Tanzânia
7.
Br J Cancer ; 123(4): 534-541, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32499569

RESUMO

BACKGROUND: Host-microbiota interactions shape T-cell differentiation and promote tumour immunity. Although IL-9-producing T cells have been described as potent antitumour effectors, their role in microbiota-mediated tumour control remains unclear. METHODS: We analysed the impact of the intestinal microbiota on the differentiation of colonic lamina propria IL-9-producing T cells in germ-free and dysbiotic mice. Systemic effects of the intestinal microbiota on IL-9-producing T cells and the antitumour role of IL-9 were analysed in a model of melanoma-challenged dysbiotic mice. RESULTS: We show that germ-free mice have lower frequency of colonic lamina propria IL-9-producing T cells when compared with conventional mice, and that intestinal microbiota reconstitution restores cell frequencies. Long-term antibiotic treatment promotes host dysbiosis, diminishes intestinal IL-4 and TGF-ß gene expression, decreases the frequency of colonic lamina propria IL-9-producing T cells, increases the susceptibility to tumour development and reduces the frequency of IL-9-producing T cells in the tumour microenvironment. Faecal transplant restores intestinal microbiota diversity, and the frequency of IL-9-producing T cells in the lungs of dysbiotic animals, restraining tumour burden. Finally, recombinant IL-9 injection enhances tumour control in dysbiotic mice. CONCLUSIONS: Host-microbiota interactions are required for adequate differentiation and antitumour function of IL-9-producing T cells.


Assuntos
Antibacterianos/efeitos adversos , Disbiose/imunologia , Vida Livre de Germes , Interleucina-9/metabolismo , Melanoma/microbiologia , Linfócitos T/imunologia , Animais , Diferenciação Celular , Linhagem Celular Tumoral , Disbiose/induzido quimicamente , Disbiose/terapia , Transplante de Microbiota Fecal , Microbioma Gastrointestinal , Interleucina-4/metabolismo , Masculino , Melanoma/imunologia , Camundongos , Mucosa/efeitos dos fármacos , Mucosa/imunologia , Transplante de Neoplasias , Linfócitos T/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Microambiente Tumoral
8.
Acta Paediatr ; 109(1): 71-77, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31240753

RESUMO

AIM: Our aim was to investigate the effects of timing of cord clamping on the risk of hyperbilirubinaemia. METHODS: We recruited 540 normal vaginal deliveries at the Paropakar Maternity and Women's Hospital in Kathmandu, Nepal, from October 2 to November 21, 2014. They were randomised into two groups: 257/270 were cord clamped within 60 seconds and 209/270 after 180 seconds. Transcutaneous bilirubin was measured at discharge and 24 hours. At 4 weeks, 506 mothers were successfully contacted by phone, and the health status of the baby and their history of jaundice and treatment was recorded. RESULTS: Based on transcutaneous bilirubin at discharge, 22/261 (8.4%) in the early group and 25/263 (9.5%) in the delayed group (P = 0.76) were at high risk of subsequent hyperbilirubinemia. At the 4-week follow-up, jaundice was reported in 13/253 (5.1%) in the early and 17/253 (6.7%) in the delayed group (P = 0.57) and 3/253 (1.2 %) of the early and 1/253 (0.4%) of the delayed group (P = 0.62) received treatment. All analyses were based on intention-to-treat. CONCLUSION: Delayed cord clamping was not associated with an increased risk of hyperbilirubinaemia during the first day of life or risk of jaundice within 4 weeks compared with the early group.


Assuntos
Icterícia Neonatal/epidemiologia , Cordão Umbilical , Constrição , Feminino , Humanos , Recém-Nascido , Masculino , Nepal/epidemiologia , Fatores de Tempo
9.
BMC Pediatr ; 16: 35, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26965317

RESUMO

BACKGROUND: Delayed cord clamping at birth has shown to benefit neonates with increased placental transfusion leading to higher haemoglobin concentrations, additional iron stores and less anaemia later in infancy, higher red blood cell flow to vital organs and better cardiopulmonary adaptation. As iron deficiency in infants even without anaemia has been associated with impaired development, delayed cord clamping seems to benefit full term infants also in regions with a relatively low prevalence of iron deficiency anaemia. In Nepal, there is a high anaemia prevalence among children between 6 and 17 months (72-78 %). The objective of the proposed study is to evaluate the effects of delayed and early cord clamping on anaemia (and haemoglobin level) at 8 and 12 months, ferritin at 8 and 12 months, bilirubin at 2-3 days, admission to Neonatal Intensive Care Unit (NICU) or special care nursery, and development at 12 and 18-24 months of age. METHODS/DESIGN: A randomized, controlled trial comparing delayed and early cord clamping will be implemented at Paropakar Maternity and Women's Hospital in Kathmandu, Nepal. Pregnant woman of gestational age 34-41 weeks who deliver vaginally will be included in the study. The interventions will consist of delayed clamping of the umbilical cord (≥180 s after delivery) or early clamping of the umbilical cord (≤60 s). At 8 and 12 months of age, infant's iron status and developmental milestones will be measured. DISCUSSION: This trial is important to perform because, although strong indications for the beneficial effect of delayed cord clamping on anaemia at 8 to 12 months of age exist, it has not yet been evaluated by a randomized trial in this setting. The proposed study will analyse both outcome as well as safety effects. Additionally, the results may not only contribute to practice in Nepal, but also to the global community, in particular to other low-income countries with a high prevalence of iron deficiency anaemia. TRIAL REGISTRATION: Clinical trial.gov NCT02222805 . Registered August 19 2014.


Assuntos
Anemia Ferropriva/prevenção & controle , Doenças do Prematuro/prevenção & controle , Assistência Perinatal/métodos , Cordão Umbilical , Anemia Ferropriva/sangue , Anemia Ferropriva/diagnóstico , Anemia Ferropriva/etiologia , Bilirrubina/sangue , Biomarcadores/sangue , Feminino , Ferritinas/sangue , Hemoglobinas/metabolismo , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/sangue , Doenças do Prematuro/diagnóstico , Doenças do Prematuro/etiologia , Nepal , Gravidez , Nascimento a Termo , Fatores de Tempo , Resultado do Tratamento
10.
Nat Commun ; 15(1): 451, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38200005

RESUMO

Immune cells must adapt to different environments during the course of an immune response. Here we study the adaptation of CD8+ T cells to the intestinal microenvironment and how this process shapes the establishment of the CD8+ T cell pool. CD8+ T cells progressively remodel their transcriptome and surface phenotype as they enter the gut wall, and downregulate expression of mitochondrial genes. Human and mouse intestinal CD8+ T cells have reduced mitochondrial mass, but maintain a viable energy balance to sustain their function. We find that the intestinal microenvironment is rich in prostaglandin E2 (PGE2), which drives mitochondrial depolarization in CD8+ T cells. Consequently, these cells engage autophagy to clear depolarized mitochondria, and enhance glutathione synthesis to scavenge reactive oxygen species (ROS) that result from mitochondrial depolarization. Impairing PGE2 sensing promotes CD8+ T cell accumulation in the gut, while tampering with autophagy and glutathione negatively impacts the T cell pool. Thus, a PGE2-autophagy-glutathione axis defines the metabolic adaptation of CD8+ T cells to the intestinal microenvironment, to ultimately influence the T cell pool.


Assuntos
Autofagia , Linfócitos T CD8-Positivos , Humanos , Animais , Camundongos , Dinoprostona , Genes Mitocondriais , Glutationa
11.
Indian J Thorac Cardiovasc Surg ; 39(4): 417-420, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37346429

RESUMO

Congenital pulmonary airway malformation (CPAM) is congenital pulmonary anomaly characterized by multicystic areas, over-distension, and proliferation of terminal bronchioles with lack of normal alveoli. Clinical presentation may vary from mild respiratory symptoms to severe respiratory distress and frequent pneumothoraxes. We report a rare case of neonatal CPAM type I manifested with neonatal respiratory distress and pneumothorax, which was managed successfully with left lower lobectomy. Supplementary Information: The online version contains supplementary material available at 10.1007/s12055-023-01510-x.

12.
iScience ; 26(10): 107719, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37674984

RESUMO

Little is known about the effects of high-fat diet (HFD)-induced obesity on resident colonic lamina propria (LP) macrophages (LPMs) function and metabolism. Here, we report that obesity and diabetes resulted in increased macrophage infiltration in the colon. These macrophages exhibited the residency phenotype CX3CR1hiMHCIIhi and were CD4-TIM4-. During HFD, resident colonic LPM exhibited a lipid metabolism gene expression signature that overlapped that used to define lipid-associated macrophages (LAMs). Via single-cell RNA sequencing, we identified a sub-cluster of macrophages, increased in HFD, that were responsible for the LAM signature. Compared to other macrophages in the colon, these cells were characterized by elevated glycolysis, phagocytosis, and efferocytosis signatures. CX3CR1hiMHCIIhi colonic resident LPMs had fewer lipid droplets (LDs) and decreased triacylglycerol (TG) content compared to equivalent cells in lean mice and exhibited increased phagocytic capacity, suggesting that HFD induces adaptive responses in LPMs to limit bacterial translocation.

13.
bioRxiv ; 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36993703

RESUMO

Immune cells must adapt to different environments during the course of an immune response. We studied the adaptation of CD8 + T cells to the intestinal microenvironment and how this process shapes their residency in the gut. CD8 + T cells progressively remodel their transcriptome and surface phenotype as they acquire gut residency, and downregulate expression of mitochondrial genes. Human and mouse gut-resident CD8 + T cells have reduced mitochondrial mass, but maintain a viable energy balance to sustain their function. We found that the intestinal microenvironment is rich in prostaglandin E 2 (PGE 2 ), which drives mitochondrial depolarization in CD8 + T cells. Consequently, these cells engage autophagy to clear depolarized mitochondria, and enhance glutathione synthesis to scavenge reactive oxygen species (ROS) that result from mitochondrial depolarization. Impairing PGE 2 sensing promotes CD8 + T cell accumulation in the gut, while tampering with autophagy and glutathione negatively impacts the T cell population. Thus, a PGE 2 -autophagy-glutathione axis defines the metabolic adaptation of CD8 + T cells to the intestinal microenvironment, to ultimately influence the T cell pool.

14.
Sci Immunol ; 7(76): eadd3263, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36240286

RESUMO

Type 2 immunity is associated with adipose tissue (AT) homeostasis and infection with parasitic helminths, but whether AT participates in immunity to these parasites is unknown. We found that the fat content of mesenteric AT (mAT) declined in mice during infection with a gut-restricted helminth. This was associated with the accumulation of metabolically activated, interleukin-33 (IL-33), thymic stromal lymphopoietin (TSLP), and extracellular matrix (ECM)-producing stromal cells. These cells shared transcriptional features, including the expression of Dpp4 and Pi16, with multipotent progenitor cells (MPC) that have been identified in numerous tissues and are reported to be capable of differentiating into fibroblasts and adipocytes. Concomitantly, mAT became infiltrated with resident T helper 2 (TH2) cells that responded to TSLP and IL-33 by producing stromal cell-stimulating cytokines, including transforming growth factor ß1 (TGFß1) and amphiregulin. These TH2 cells expressed genes previously associated with type 2 innate lymphoid cells (ILC2), including Nmur1, Calca, Klrg1, and Arg1, and persisted in mAT for at least 11 months after anthelmintic drug-mediated clearance of infection. We found that MPC and TH2 cells localized to ECM-rich interstitial spaces that appeared shared between mesenteric lymph node, mAT, and intestine. Stromal cell expression of epidermal growth factor receptor (EGFR), the receptor for amphiregulin, was required for immunity to infection. Our findings point to the importance of MPC and TH2 cell interactions within the interstitium in orchestrating AT remodeling and immunity to an intestinal infection.


Assuntos
Imunidade Inata , Interleucina-33 , Tecido Adiposo/metabolismo , Anfirregulina , Animais , Citocinas/metabolismo , Dipeptidil Peptidase 4 , Receptores ErbB , Linfócitos , Camundongos , Células Th2 , Fator de Crescimento Transformador beta1
15.
Cell Death Differ ; 28(7): 2194-2206, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33649469

RESUMO

Optic atrophy 1 (OPA1), a mitochondria-shaping protein controlling cristae biogenesis and respiration, is required for memory T cell function, but whether it affects intrathymic T cell development is unknown. Here we show that OPA1 is necessary for thymocyte maturation at the double negative (DN)3 stage when rearrangement of the T cell receptor ß (Tcrß) locus occurs. By profiling mitochondrial function at different stages of thymocyte maturation, we find that DN3 cells rely on oxidative phosphorylation. Consistently, Opa1 deletion during early T cell development impairs respiration of DN3 cells and reduces their number. Opa1-deficient DN3 cells indeed display stronger TCR signaling and are more prone to cell death. The surviving Opa1-/- thymocytes that reach the periphery as mature T cells display an effector memory phenotype even in the absence of antigenic stimulation but are unable to generate metabolically fit long-term memory T cells. Thus, mitochondrial defects early during T cell development affect mature T cell function.


Assuntos
GTP Fosfo-Hidrolases/metabolismo , Células T de Memória/metabolismo , Mitocôndrias/metabolismo , Animais , Diferenciação Celular , GTP Fosfo-Hidrolases/genética , Células T de Memória/citologia , Camundongos , Camundongos Knockout , Fosforilação Oxidativa , Transdução de Sinais , Timo/citologia , Timo/metabolismo
16.
Mol Biol Rep ; 37(2): 703-10, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19449127

RESUMO

Glutamine synthetase is a very important enzyme of ammonium assimilation in plants. Here, we report on the regulation of a cytosolic glutamine synthetase (CsGS) from Camellia sinensis (L.) O. Kuntze during developmental stages and light/dark conditions on the utilization of nitrate and ammonia. The CsGS expression levels decreased during dormancy compared to non-dormancy phase of growth. Different leaf positions present different ages of the leaf and CsGS expression level was highest in apical bud (youngest leaf) and lower in mature fourth leaf, suggesting transcriptional regulation of CsGS during developmental stages. The CsGS enzyme activity showed similar trend to that of expression during developmental stages. The nitrate, ammonium and total amino acid contents were increased upon exposure to both N-sources during light and dark conditions. During light conditions, expression of CsGS in apical bud increased upon exposure to both N-sources nitrate and ammonium. While during dark conditions expression was increased only by ammonium and nitrate had no influence. Exposure to both N-sources also showed enhancing effect on CsGS enzyme activity during light. Under dark, ammonium application increased CsGS enzyme activity and nitrate had inhibitory effect on the activity. Results suggest the transcriptional regulation of CsGS on N-utilization during light/dark conditions.


Assuntos
Camellia sinensis/crescimento & desenvolvimento , Camellia sinensis/genética , Camellia sinensis/metabolismo , Glutamato-Amônia Ligase/genética , Nitrogênio/metabolismo , Alimentos , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Genes de Plantas/fisiologia , Glutamato-Amônia Ligase/metabolismo , Luz , Fotoperíodo , Transcrição Gênica
17.
Cell Metab ; 31(2): 391-405.e8, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31761564

RESUMO

Pyruvate kinase (PK) catalyzes the conversion of phosphoenolpyruvate to pyruvate during glycolysis. The PK isoform PKM2 has additional roles in regulation of gene transcription and protein phosphorylation. PKM2 has been shown to control macrophage metabolic remodeling in inflammation, but its role in T cell biology is poorly understood. Here, we report PKM2 upregulation, phosphorylation, and nuclear accumulation in murine and human CD4+ T cells following activation in vitro. Treatment of T cells with TEPP-46, an allosteric activator that induces PKM2 tetramerization and blocks its nuclear translocation, strongly reduces their activation, proliferation, and cytokine production by inhibiting essential signaling pathways and thus preventing the engagement of glycolysis. TEPP-46 limits the development of both T helper 17 (Th17) and Th1 cells in vitro and ameliorates experimental autoimmune encephalomyelitis (EAE) in vivo. Overall, our results suggest that pharmacological targeting of PKM2 may represent a valuable therapeutic approach in T cell-mediated inflammation and autoimmunity.


Assuntos
Proteínas de Transporte/metabolismo , Ativadores de Enzimas/farmacologia , Proteínas de Membrana/metabolismo , Piridazinas/farmacologia , Pirróis/farmacologia , Células Th1 , Hormônios Tireóideos/metabolismo , Animais , Autoimunidade/efeitos dos fármacos , Células Cultivadas , Feminino , Humanos , Inflamação/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Células Th1/citologia , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Proteínas de Ligação a Hormônio da Tireoide
18.
Nat Commun ; 11(1): 4107, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796836

RESUMO

Foamy macrophages, which have prominent lipid droplets (LDs), are found in a variety of disease states. Toll-like receptor agonists drive triacylglycerol (TG)-rich LD development in macrophages. Here we explore the basis and significance of this process. Our findings indicate that LD development is the result of metabolic commitment to TG synthesis on a background of decreased fatty acid oxidation. TG synthesis is essential for optimal inflammatory macrophage activation as its inhibition, which prevents LD development, has marked effects on the production of inflammatory mediators, including IL-1ß, IL-6 and PGE2, and on phagocytic capacity. The failure of inflammatory macrophages to make PGE2 when TG-synthesis is inhibited is critical for this phenotype, as addition of exogenous PGE2 is able to reverse the anti-inflammatory effects of TG synthesis inhibition. These findings place LDs in a position of central importance in inflammatory macrophage activation.


Assuntos
Inflamação/metabolismo , Lipidômica/métodos , Triglicerídeos/metabolismo , Animais , Células Cultivadas , Citometria de Fluxo , Glucose/metabolismo , Glicerol/metabolismo , Células HEK293 , Humanos , Metabolismo dos Lipídeos/fisiologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Microscopia Eletrônica , Palmitatos/metabolismo , Análise de Sequência de RNA
19.
PLoS One ; 14(6): e0218031, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31188895

RESUMO

AIM: To explore delivery care staff's perceptions and attitudes towards changes in practice of umbilical cord clamping in order to identify work culture barriers and enablers for improved clinical practice and implementation of the new guidelines on cord clamping. METHOD: A purposive sampling strategy was used to include delivery staff at two major hospitals in Kathmandu, Nepal for focus group discussions. Key informant interviews were conducted with the ward in-charges and skilled birth attendant trainers at the respective hospitals. Data were analyzed using qualitative content analysis. RESULT: Eight focus group discussions altogether with 34 delivery care staff working in the labor room and birthing units, and 12 key informant interviews with skilled birth attendant trainers/supervisors and ward in-charges from both hospitals participated in the study. Participants had positive attitudes towards delayed cord clamping as it was not perceived to be a difficult task and as they perceived it to be beneficial for mother and child. The "will to do good", and a high level of trust both in the hierarchical system as well as in scientific evidence were identified as promoters of change. Several barriers were mentioned, such as maternal or fetal medical conditions and physical settings, as constraints to perform delayed cord clamping. They also mentioned difficulties in adopting new guidelines due to habitual practice, lack of formal training and poor coherence within the work team. In order to bring change to the practice, participants highlighted that officially approved national and institutional protocols and regular training are crucial. CONCLUSION: Due to poor coherence within the health system and lack of national or institutional protocols, delivery staff has to rely on their own initiative to develop skills and are left to informal decision making, and are therefore hesitant to apply new routines. In order to change cord clamping practices to align with evidence and policies health-care staff needs to be better supported by the governance structures of the health system, with clear and approved guidelines made available and coherent training and support.


Assuntos
Atitude do Pessoal de Saúde , Parto Obstétrico , Conhecimentos, Atitudes e Prática em Saúde , Unidade Hospitalar de Ginecologia e Obstetrícia/organização & administração , Cordão Umbilical/cirurgia , Adulto , Feminino , Grupos Focais , Humanos , Recém-Nascido , Nepal , Unidade Hospitalar de Ginecologia e Obstetrícia/ética , Guias de Prática Clínica como Assunto , Gravidez , Instrumentos Cirúrgicos
20.
Neonatology ; 115(1): 36-42, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30278462

RESUMO

BACKGROUND: Delayed cord clamping (DCC) is associated with an improved iron status at 8 months, a reduction of anemia at 12 months, and an improved development at 4 years. Assessment of the development after DCC has not been performed earlier in a setting with a high prevalence of iron deficiency. OBJECTIVE: The aim of this paper was to investigate the effects of DCC compared to early cord clamping (ECC) on the development evaluated with the Ages and Stages Questionnaire (ASQ) at 12 months of age. METHOD: We conducted a randomized controlled trial investigating the effect of DCC (≥180 s) versus ECC (≤60 s) in 540 full-term deliveries. Twelve months after delivery, the parents reported their infant's development by ASQ. Infants having a score < 1 standard deviation (SD) under the mean score were considered "at risk" of affected neurodevelopment. RESULTS: At 12 months of age, 332 (61.5%) infants were assessed. Fewer children in the DCC group were "at risk" of having affected neurodevelopment measured by the ASQ total score, 21 (7.8%) versus 49 (18.1%) in the ECC group. The relative risk was 0.43 (0.26-0.71). Infants in the DCC group had higher mean total scores (SD), 290.4 (10.4) versus 287.2 (10.1), p = 0.01. Significantly fewer infants in the delayed group were "at risk" and had higher scores in the domains "communication", "gross motor", and "personal-social". CONCLUSIONS: DCC after 3 min was associated with an improvement of the overall neurodevelopment assessed at 12 months of age as compared to infants in the group with cord clamping within 1 min.


Assuntos
Anemia Ferropriva/prevenção & controle , Encéfalo/fisiologia , Desenvolvimento Infantil/fisiologia , Ferritinas/sangue , Cordão Umbilical/cirurgia , Constrição , Parto Obstétrico , Feminino , Seguimentos , Humanos , Lactente , Modelos Lineares , Masculino , Análise Multivariada , Nepal , Gravidez , Nascimento a Termo , Centros de Atenção Terciária , Fatores de Tempo
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