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1.
Cell Rep Med ; 5(2): 101393, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38280376

RESUMO

In metastatic urothelial cancer (mUC), cisplatin versus carboplatin leads to durable disease control in a subset of patients. The IMvigor130 trial reveals more favorable effects with atezolizumab combined with gemcitabine and cisplatin (GemCis) versus gemcitabine and carboplatin (GemCarbo). This study investigates the immunomodulatory effects of cisplatin as a potential explanation for these observations. Our findings indicate that improved outcomes with GemCis versus GemCarbo are primarily observed in patients with pretreatment tumors exhibiting features of restrained adaptive immunity. In addition, GemCis versus GemCarbo ± atezolizumab induces transcriptional changes in circulating immune cells, including upregulation of antigen presentation and T cell activation programs. In vitro experiments demonstrate that cisplatin, compared with carboplatin, exerts direct immunomodulatory effects on cancer cells, promoting dendritic cell activation and antigen-specific T cell killing. These results underscore the key role of immune modulation in cisplatin's efficacy in mUC and highlight the importance of specific chemotherapy backbones in immunotherapy combination regimens.


Assuntos
Anticorpos Monoclonais Humanizados , Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Neoplasias Urológicas , Humanos , Carboplatina/uso terapêutico , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/induzido quimicamente , Carcinoma de Células de Transição/patologia , Cisplatino/uso terapêutico , Desoxicitidina/uso terapêutico , Gencitabina , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Neoplasias Urológicas/tratamento farmacológico , Neoplasias Urológicas/induzido quimicamente , Neoplasias Urológicas/patologia
2.
Immunity ; 54(10): 2338-2353.e6, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34534439

RESUMO

In tumors, a subset of CD8+ T cells expressing the transcription factor TCF-1 drives the response to immune checkpoint blockade. We examined the mechanisms that maintain these cells in an autochthonous model of lung adenocarcinoma. Longitudinal sampling and single-cell sequencing of tumor-antigen specific TCF-1+ CD8+ T cells revealed that while intratumoral TCF-1+ CD8+ T cells acquired dysfunctional features and decreased in number as tumors progressed, TCF-1+ CD8+ T cell frequency in the tumor draining LN (dLN) remained stable. Two discrete intratumoral TCF-1+ CD8+ T cell subsets developed over time-a proliferative SlamF6+ subset and a non-cycling SlamF6- subset. Blocking dLN egress decreased the frequency of intratumoral SlamF6+ TCF-1+ CD8+ T cells. Conventional type I dendritic cell (cDC1) in dLN decreased in number with tumor progression, and Flt3L+anti-CD40 treatment recovered SlamF6+ T cell frequencies and decreased tumor burden. Thus, cDC1s in tumor dLN maintain a reservoir of TCF-1+ CD8+ T cells and their decrease contributes to failed anti-tumor immunity.


Assuntos
Adenocarcinoma de Pulmão/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Neoplasias Pulmonares/imunologia , Linfonodos/imunologia , Fator 1 de Transcrição de Linfócitos T/imunologia , Animais , Camundongos , Subpopulações de Linfócitos T/imunologia
3.
Cell ; 184(11): 3056-3074.e21, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-33932339

RESUMO

The choroid plexus (ChP) in each brain ventricle produces cerebrospinal fluid (CSF) and forms the blood-CSF barrier. Here, we construct a single-cell and spatial atlas of each ChP in the developing, adult, and aged mouse brain. We delineate diverse cell types, subtypes, cell states, and expression programs in epithelial and mesenchymal cells across ages and ventricles. In the developing ChP, we predict a common progenitor pool for epithelial and neuronal cells, validated by lineage tracing. Epithelial and fibroblast cells show regionalized expression by ventricle, starting at embryonic stages and persisting with age, with a dramatic transcriptional shift with maturation, and a smaller shift in each aged cell type. With aging, epithelial cells upregulate host-defense programs, and resident macrophages upregulate interleukin-1ß (IL-1ß) signaling genes. Our atlas reveals cellular diversity, architecture and signaling across ventricles during development, maturation, and aging of the ChP-brain barrier.


Assuntos
Plexo Corióideo/embriologia , Plexo Corióideo/metabolismo , Fatores Etários , Envelhecimento/fisiologia , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Encéfalo/fisiologia , Encefalopatias/genética , Encefalopatias/fisiopatologia , Diferenciação Celular/genética , Linhagem da Célula/genética , Plexo Corióideo/fisiologia , Células Epiteliais/metabolismo , Feminino , Masculino , Camundongos/embriologia , Camundongos Endogâmicos C57BL , Transdução de Sinais , Análise de Célula Única
4.
Endocr Pract ; 26(2): 218-225, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31652101

RESUMO

Objective: Perioperative glucocorticoids are commonly given to reduce pain and nausea in patients undergoing surgery. However, the glycemic effects of steroids and the potential effects on morbidity and mortality have not been systematically evaluated. This study investigated the association between perioperative dexamethasone and postoperative blood glucose, hospital length of stay (LOS), readmission rates, and 90-day survival. Methods: Data from 4,800 consecutive orthopedic surgery patients who underwent surgery between 2000 and 2016 within a single health system were analyzed retrospectively. Results: Patients with and without diabetes mellitus (DM) who were given a single dose of dexamethasone had higher rates of hyperglycemia during the first 24 hours after surgery as compared to those who did not receive dexamethasone (hazard ratio [HR] was 1.81, and 95% confidence interval [CI] was [1.46, 2.24] for the DM cohort; HR 2.34, 95% CI [1.66, 3.29] for the nonDM cohort). LOS was nearly 1 day shorter in patients who received dexamethasone (geometric mean ratio [GMR] 0.79, 95% CI [0.75, 0.83] for patients with DM; GMR 0.75, 95% CI [0.72, 0.79] for patients without DM), and there was no difference in 90-day readmission rates. In patients without DM, dexamethasone was associated with a higher 90-day overall survival (99.07% versus 96.90%; P = .004). Conclusion: In patients with and without DM who undergo orthopedic surgery, perioperative dexamethasone was associated with a transiently higher risk of hyperglycemia. However, dexamethasone treatment was associated with a shorter LOS in patients with and without DM, and a higher overall 90-day survival rate in patients without DM, compared to patients who did not receive dexamethasone. Abbreviations: BMI = body mass index; CAD = coronary artery disease; CI = confidence interval; DM = diabetes mellitus; GMR = geometric mean ratio; HR = hazard ratio; IV = intravenous; LOS = length of stay; POD = postoperative day.


Assuntos
Dexametasona/uso terapêutico , Hiperglicemia , Glicemia , Humanos , Hiperglicemia/tratamento farmacológico , Tempo de Internação , Complicações Pós-Operatórias , Período Pós-Operatório , Estudos Retrospectivos
5.
Cell Rep ; 29(10): 2998-3008.e8, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31801068

RESUMO

Regulatory T cells (Tregs) can impair anti-tumor immune responses and are associated with poor prognosis in multiple cancer types. Tregs in human tumors span diverse transcriptional states distinct from those of peripheral Tregs, but their contribution to tumor development remains unknown. Here, we use single-cell RNA sequencing (RNA-seq) to longitudinally profile dynamic shifts in the distribution of Tregs in a genetically engineered mouse model of lung adenocarcinoma. In this model, interferon-responsive Tregs are more prevalent early in tumor development, whereas a specialized effector phenotype characterized by enhanced expression of the interleukin-33 receptor ST2 is predominant in advanced disease. Treg-specific deletion of ST2 alters the evolution of effector Treg diversity, increases infiltration of CD8+ T cells into tumors, and decreases tumor burden. Our study shows that ST2 plays a critical role in Treg-mediated immunosuppression in cancer, highlighting potential paths for therapeutic intervention.


Assuntos
Interleucina-33/imunologia , Transdução de Sinais/imunologia , Linfócitos T Reguladores/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Feminino , Tolerância Imunológica/imunologia , Terapia de Imunossupressão/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Microambiente Tumoral/imunologia
6.
Immunity ; 51(4): 709-723.e6, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31604686

RESUMO

Neuroimmune interactions have emerged as critical modulators of allergic inflammation, and type 2 innate lymphoid cells (ILC2s) are an important cell type for mediating these interactions. Here, we show that ILC2s expressed both the neuropeptide calcitonin gene-related peptide (CGRP) and its receptor. CGRP potently inhibited alarmin-driven type 2 cytokine production and proliferation by lung ILC2s both in vitro and in vivo. CGRP induced marked changes in ILC2 expression programs in vivo and in vitro, attenuating alarmin-driven proliferative and effector responses. A distinct subset of ILCs scored highly for a CGRP-specific gene signature after in vivo alarmin stimulation, suggesting CGRP regulated this response. Finally, we observed increased ILC2 proliferation and type 2 cytokine production as well as exaggerated responses to alarmins in mice lacking the CGRP receptor. Together, these data indicate that endogenous CGRP is a critical negative regulator of ILC2 responses in vivo.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Linfócitos/fisiologia , Neuropeptídeos/metabolismo , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Alarminas/metabolismo , Animais , Peptídeo Relacionado com Gene de Calcitonina/genética , Proliferação de Células , Células Cultivadas , Retroalimentação Fisiológica , Imunidade Inata , Interleucina-33/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuroimunomodulação , Neuropeptídeos/genética , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/genética , Transdução de Sinais , Células Th2/imunologia
7.
Cell ; 178(3): 714-730.e22, 2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31348891

RESUMO

Genome-wide association studies (GWAS) have revealed risk alleles for ulcerative colitis (UC). To understand their cell type specificities and pathways of action, we generate an atlas of 366,650 cells from the colon mucosa of 18 UC patients and 12 healthy individuals, revealing 51 epithelial, stromal, and immune cell subsets, including BEST4+ enterocytes, microfold-like cells, and IL13RA2+IL11+ inflammatory fibroblasts, which we associate with resistance to anti-TNF treatment. Inflammatory fibroblasts, inflammatory monocytes, microfold-like cells, and T cells that co-express CD8 and IL-17 expand with disease, forming intercellular interaction hubs. Many UC risk genes are cell type specific and co-regulated within relatively few gene modules, suggesting convergence onto limited sets of cell types and pathways. Using this observation, we nominate and infer functions for specific risk genes across GWAS loci. Our work provides a framework for interrogating complex human diseases and mapping risk variants to cell types and pathways.


Assuntos
Colite Ulcerativa/patologia , Colo/metabolismo , Adulto , Idoso , Anticorpos Monoclonais/uso terapêutico , Bestrofinas/metabolismo , Antígenos CD8/metabolismo , Estudos de Casos e Controles , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Colo/patologia , Enterócitos/citologia , Enterócitos/metabolismo , Feminino , Loci Gênicos , Estudo de Associação Genômica Ampla , Humanos , Interleucina-17/metabolismo , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Linfócitos T/citologia , Linfócitos T/metabolismo , Trombospondinas/metabolismo , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
8.
Endocr Pract ; 25(9): 908-917, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31170369

RESUMO

Objective: Thyroid nodules with indeterminate cytology pose management challenges in clinical practice. The aim of this study was to determine the efficacy of ultrasound features in navigating clinical decision making in thyroid nodules with indeterminate cytology. Methods: We retrospectively reviewed ultrasound imaging from 186 adult patients with thyroid nodules and indeterminate cytology who underwent thyroidectomy at a quaternary hospital from 2010-2017. All nodules were classified based on the American Thyroid Association (ATA) and 2017 American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS). Nodules were included if good quality pre-operative ultrasound imaging and surgical pathology were available. Results: A total of 202 thyroid nodules were included. The median age was 57 years; 82.8% were female. Risk of malignancy (ROM) in resected nodules with Bethesda 3 and 4 cytology was 19.4% and 30.3%, respectively. ATA high-suspicious and TI-RADS 5 nodules had high ROM, 100% in both systems for Bethesda 3 nodules; 66.7% and 50.0%, respectively, for Bethesda 4 nodules. For ATA very-low suspicious/TI-RADS 1 and 2, ROM was 0%. ROM in ATA low-suspicious/TI-RADS 3 nodules with Bethesda 3 cytology was lower (15.2% and 16.0%, respectively) than Bethesda 4 cytology (33.8% and 34.3%, respectively). ATA intermediate-suspicious/TI-RADS 4 nodules with Bethesda 4 cytology had a lower ROM (11.1% and 18.2%, respectively) than Bethesda 3 cytology (28.6 % and 31.6%, respectively). Conclusion: Using either the ATA or the TI-RADS system to risk-stratify nodules with indeterminate cytology may help clinicians plan better for additional diagnostic testing and treatment. Abbreviations: ACR = American College of Radiology; ATA = American Thyroid Association; AUS = atypia of undetermined significance; FLUS = follicular lesion of undetermined significance; FN = follicular neoplasm; PPV = positive predictive value; ROM = risk of malignancy; SFN = suspicious for follicular neoplasm; TI-RADS = Thyroid Imaging Reporting and Data System.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ultrassonografia
9.
Cell ; 175(5): 1307-1320.e22, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30392957

RESUMO

In the small intestine, a niche of accessory cell types supports the generation of mature epithelial cell types from intestinal stem cells (ISCs). It is unclear, however, if and how immune cells in the niche affect ISC fate or the balance between self-renewal and differentiation. Here, we use single-cell RNA sequencing (scRNA-seq) to identify MHC class II (MHCII) machinery enrichment in two subsets of Lgr5+ ISCs. We show that MHCII+ Lgr5+ ISCs are non-conventional antigen-presenting cells in co-cultures with CD4+ T helper (Th) cells. Stimulation of intestinal organoids with key Th cytokines affects Lgr5+ ISC renewal and differentiation in opposing ways: pro-inflammatory signals promote differentiation, while regulatory cells and cytokines reduce it. In vivo genetic perturbation of Th cells or MHCII expression on Lgr5+ ISCs impacts epithelial cell differentiation and IEC fate during infection. These interactions between Th cells and Lgr5+ ISCs, thus, orchestrate tissue-wide responses to external signals.


Assuntos
Diferenciação Celular , Autorrenovação Celular , Interleucina-10/metabolismo , Células-Tronco/citologia , Linfócitos T Auxiliares-Indutores/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Autorrenovação Celular/efeitos dos fármacos , Citocinas/farmacologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Feminino , Antígenos de Histocompatibilidade Classe II/metabolismo , Sistema Imunitário/metabolismo , Intestinos/citologia , Intestinos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Organoides/citologia , Organoides/efeitos dos fármacos , Organoides/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Salmonella enterica/patogenicidade , Células-Tronco/metabolismo , Linfócitos T Auxiliares-Indutores/citologia
10.
J Womens Health (Larchmt) ; 27(8): 982-986, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29746188

RESUMO

INTRODUCTION: Type 2 diabetes and prediabetes are heterogeneous diseases that directly affect over 115 million Americans. Considerable gender differences exist with regard to diabetes risk factors, hormonal effects on glucose, and cardiovascular outcomes. MATERIALS AND METHODS: Historically, diabetes studies have largely focused on men with the assumption that the data can safely be extrapolated to women. However, more recent investigations have illuminated significant differences between genders. RESULTS: Women are at higher risk of death from cardiovascular disease (CVD), are more likely to die following a myocardial infarction, and are treated less aggressively toward glycemic targets. Additionally, pregnancy and menopause have profound effects on the risks for diabetes and therefore warrant more aggressive diagnostic attention and monitoring. It is important for practitioners to understand that women who have gestational diabetes are at an increased risk for CVD even if they do not develop diabetes. Older age brings additional challenges with diabetes, including increased fracture risk even with normal bone mineral density. CONCLUSION: Recognizing the stages of life that are unique to women is critical as treatment and patient education can significantly impact patient well-being and outcomes. This article describes female-specific characteristics of prediabetes and diabetes during several distinct phases of life, including pregnancy, menopause, and older age. Diagnostic and management strategies for these populations are also discussed.


Assuntos
Doenças Cardiovasculares/terapia , Diabetes Mellitus Tipo 2/terapia , Infarto do Miocárdio/terapia , Adulto , Glicemia , Doenças Cardiovasculares/complicações , Diabetes Mellitus Tipo 2/complicações , Diabetes Gestacional , Feminino , Humanos , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Estado Pré-Diabético , Gravidez , Fatores de Risco , Fatores Sexuais
11.
Am J Med Qual ; 33(6): 598-603, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29553285

RESUMO

Intravenous insulin with glucose is used in urgent treatment for hyperkalemia but has a significant risk of hypoglycemia. The authors developed an order panel within the electronic health record system that utilizes weight-based insulin dosing and standardized blood glucose monitoring to reduce hypoglycemia. As initial evaluation of this protocol, the authors retrospectively compared potassium and blood glucose lowering in patients treated with the weight-based (0.1 units/kg) insulin order panel (n = 195) with those given insulin based on provider judgment (n = 69). Serum potassium lowering did not differ between groups and there was no relationship between dose of insulin and amount of potassium lowering. There was a difference in hypoglycemia rates between groups ( P = .049), with fewer severe hypoglycemic events in the panel (2.56%) than in the non-panel group (10.14%). These data suggest weight-based insulin dosing is equally effective for lowering serum potassium and may lower risk of severe hypoglycemia.


Assuntos
Administração Intravenosa/métodos , Peso Corporal , Hiperpotassemia/tratamento farmacológico , Insulina/administração & dosagem , Idoso , Glicemia , Registros Eletrônicos de Saúde , Feminino , Humanos , Hipoglicemia/tratamento farmacológico , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Estudos Retrospectivos
12.
Nature ; 551(7680): 333-339, 2017 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-29144463

RESUMO

Intestinal epithelial cells absorb nutrients, respond to microbes, function as a barrier and help to coordinate immune responses. Here we report profiling of 53,193 individual epithelial cells from the small intestine and organoids of mice, which enabled the identification and characterization of previously unknown subtypes of intestinal epithelial cell and their gene signatures. We found unexpected diversity in hormone-secreting enteroendocrine cells and constructed the taxonomy of newly identified subtypes, and distinguished between two subtypes of tuft cell, one of which expresses the epithelial cytokine Tslp and the pan-immune marker CD45, which was not previously associated with non-haematopoietic cells. We also characterized the ways in which cell-intrinsic states and the proportions of different cell types respond to bacterial and helminth infections: Salmonella infection caused an increase in the abundance of Paneth cells and enterocytes, and broad activation of an antimicrobial program; Heligmosomoides polygyrus caused an increase in the abundance of goblet and tuft cells. Our survey highlights previously unidentified markers and programs, associates sensory molecules with cell types, and uncovers principles of gut homeostasis and response to pathogens.


Assuntos
Células Epiteliais/citologia , Epitélio/metabolismo , Intestino Delgado/citologia , Análise de Célula Única , Animais , Diferenciação Celular , Citocinas/metabolismo , Enterócitos/metabolismo , Células Epiteliais/metabolismo , Feminino , Perfilação da Expressão Gênica , Homeostase , Antígenos Comuns de Leucócito/metabolismo , Masculino , Camundongos , Organoides/citologia , Organoides/metabolismo , Celulas de Paneth/metabolismo , Transcrição Gênica , Linfopoietina do Estroma do Timo
14.
Curr Diab Rep ; 17(9): 67, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28726152

RESUMO

PURPOSE OF REVIEW: Seven trials of new agents to treat type 2 diabetes (T2DM) have been performed to assess cardiovascular (CV) safety. A significant amount of information regarding the effects of drugs in three classes is available, with new data from multiple other trials expected shortly. This article provides a summary of recently completed trials. RECENT FINDINGS: The dipeptidyl peptidase-4 inhibitors studied thus far do not alter the risk of major adverse CV events (MACE). Glucagon like peptide-1 receptor agonists liraglutide and semaglutide, and the sodium glucose cotransporter-2 inhibitor empagliflozin, significantly reduced the risk of MACE. Empagliflozin also decreased the risk of hospitalization for heart failure. Agents demonstrating a CV outcome benefit also improved parameters of renal function. Several newer antihyperglycemic agents have been found to reduce the risk of important CV complications in high-risk patients with T2DM. Future trials are needed to assess the effects of additional drugs and the impact of therapy in lower risk patients and provide additional information regarding non-CV safety outcomes.


Assuntos
Doenças Cardiovasculares/etiologia , Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Hiperglicemia/complicações , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Fatores de Risco
15.
BMC Biol ; 15(1): 38, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-28494792

RESUMO

BACKGROUND: The merging of genomes in inter-specific hybrids can result in novel phenotypes, including increased growth rate and biomass yield, a phenomenon known as heterosis. Heterosis is typically viewed as the opposite of hybrid incompatibility. In this view, the superior performance of the hybrid is attributed to heterozygote combinations that compensate for deleterious mutations accumulating in each individual genome, or lead to new, over-dominating interactions with improved performance. Still, only fragmented knowledge is available on genes and processes contributing to heterosis. RESULTS: We describe a budding yeast hybrid that grows faster than both its parents under different environments. Phenotypically, the hybrid progresses more rapidly through cell cycle checkpoints, relieves the repression of respiration in fast growing conditions, does not slow down its growth when presented with ethanol stress, and shows increased signs of DNA damage. A systematic genetic screen identified hundreds of S. cerevisiae alleles whose deletion reduced growth of the hybrid. These growth-affecting alleles were condition-dependent, and differed greatly from alleles that reduced the growth of the S. cerevisiae parent. CONCLUSIONS: Our results define a budding yeast hybrid that is perturbed in multiple regulatory processes but still shows a clear growth heterosis. We propose that heterosis results from incompatibilities that perturb regulatory mechanisms, which evolved to protect cells against damage or prepare them for future challenges by limiting cell growth.


Assuntos
Vigor Híbrido , Hibridização Genética , Fenótipo , Saccharomyces cerevisiae/genética , Alelos
16.
Cell ; 166(6): 1500-1511.e9, 2016 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-27610572

RESUMO

Reversing the dysfunctional T cell state that arises in cancer and chronic viral infections is the focus of therapeutic interventions; however, current therapies are effective in only some patients and some tumor types. To gain a deeper molecular understanding of the dysfunctional T cell state, we analyzed population and single-cell RNA profiles of CD8(+) tumor-infiltrating lymphocytes (TILs) and used genetic perturbations to identify a distinct gene module for T cell dysfunction that can be uncoupled from T cell activation. This distinct dysfunction module is downstream of intracellular metallothioneins that regulate zinc metabolism and can be identified at single-cell resolution. We further identify Gata-3, a zinc-finger transcription factor in the dysfunctional module, as a regulator of dysfunction, and we use CRISPR-Cas9 genome editing to show that it drives a dysfunctional phenotype in CD8(+) TILs. Our results open novel avenues for targeting dysfunctional T cell states while leaving activation programs intact.


Assuntos
Linfócitos T CD8-Positivos/patologia , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/patologia , Animais , Linfócitos T CD8-Positivos/imunologia , Sistemas CRISPR-Cas , Carcinogênese/genética , Carcinogênese/imunologia , Feminino , Fator de Transcrição GATA3/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Melanoma/imunologia , Melanoma/fisiopatologia , Metalotioneína/deficiência , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
17.
Cell ; 162(3): 675-86, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26189680

RESUMO

Finding the components of cellular circuits and determining their functions systematically remains a major challenge in mammalian cells. Here, we introduced genome-wide pooled CRISPR-Cas9 libraries into dendritic cells (DCs) to identify genes that control the induction of tumor necrosis factor (Tnf) by bacterial lipopolysaccharide (LPS), a key process in the host response to pathogens, mediated by the Tlr4 pathway. We found many of the known regulators of Tlr4 signaling, as well as dozens of previously unknown candidates that we validated. By measuring protein markers and mRNA profiles in DCs that are deficient in known or candidate genes, we classified the genes into three functional modules with distinct effects on the canonical responses to LPS and highlighted functions for the PAF complex and oligosaccharyltransferase (OST) complex. Our findings uncover new facets of innate immune circuits in primary cells and provide a genetic approach for dissection of mammalian cell circuits.


Assuntos
Sistemas CRISPR-Cas , Técnicas Genéticas , Imunidade Inata , Animais , Células da Medula Óssea/imunologia , Diferenciação Celular , Sobrevivência Celular , Células Dendríticas/citologia , Células Dendríticas/imunologia , Técnicas de Inativação de Genes , Redes Reguladoras de Genes , Hexosiltransferases/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Receptor 4 Toll-Like/imunologia , Fator de Necrose Tumoral alfa/imunologia
18.
Cell ; 159(1): 148-162, 2014 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-25219674

RESUMO

Pseudouridine is the most abundant RNA modification, yet except for a few well-studied cases, little is known about the modified positions and their function(s). Here, we develop Ψ-seq for transcriptome-wide quantitative mapping of pseudouridine. We validate Ψ-seq with spike-ins and de novo identification of previously reported positions and discover hundreds of unique sites in human and yeast mRNAs and snoRNAs. Perturbing pseudouridine synthases (PUS) uncovers which pseudouridine synthase modifies each site and their target sequence features. mRNA pseudouridinylation depends on both site-specific and snoRNA-guided pseudouridine synthases. Upon heat shock in yeast, Pus7p-mediated pseudouridylation is induced at >200 sites, and PUS7 deletion decreases the levels of otherwise pseudouridylated mRNA, suggesting a role in enhancing transcript stability. rRNA pseudouridine stoichiometries are conserved but reduced in cells from dyskeratosis congenita patients, where the PUS DKC1 is mutated. Our work identifies an enhanced, transcriptome-wide scope for pseudouridine and methods to dissect its underlying mechanisms and function.


Assuntos
Pseudouridina/análise , RNA Mensageiro/química , RNA não Traduzido/química , Animais , Candida albicans/genética , Candida albicans/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Disceratose Congênita/genética , Disceratose Congênita/metabolismo , Perfilação da Expressão Gênica , Humanos , Transferases Intramoleculares/química , Transferases Intramoleculares/metabolismo , Camundongos , Dados de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Pseudouridina/metabolismo , RNA/química , RNA/genética , RNA Ribossômico/química , RNA Ribossômico/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Especificidade por Substrato , Telomerase/química , Telomerase/genética
19.
Proc Natl Acad Sci U S A ; 109(51): 21010-5, 2012 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-23197825

RESUMO

Aneuploidy, an abnormal number of chromosomes, is a widespread phenomenon found in unicellulars such as yeast, as well as in plants and in mammalians, especially in cancer. Aneuploidy is a genome-scale aberration that imposes a severe burden on the cell, yet under stressful conditions specific aneuploidies confer a selective advantage. This dual nature of aneuploidy raises the question of whether it can serve as a stable and sustainable evolutionary adaptation. To clarify this, we conducted a set of laboratory evolution experiments in yeast and followed the long-term dynamics of aneuploidy under diverse conditions. Here we show that chromosomal duplications are first acquired as a crude solution to stress, yet only as transient solutions that are eliminated and replaced by more efficient solutions obtained at the individual gene level. These transient dynamics of aneuploidy were repeatedly observed in our laboratory evolution experiments; chromosomal duplications gained under stress were eliminated not only when the stress was relieved, but even if it persisted. Furthermore, when stress was applied gradually rather than abruptly, alternative solutions appear to have emerged, but not aneuploidy. Our findings indicate that chromosomal duplication is a first evolutionary line of defense, that retains survivability under strong and abrupt selective pressures, yet it merely serves as a "quick fix," whereas more refined and sustainable solutions take over. Thus, in the perspective of genome evolution trajectory, aneuploidy is a useful yet short-lived intermediate that facilitates further adaptation.


Assuntos
Aneuploidia , Duplicação Cromossômica , Cromossomos/ultraestrutura , Neoplasias/genética , Saccharomyces cerevisiae/genética , Evolução Biológica , Mapeamento Cromossômico , Meio Ambiente , Evolução Molecular , Proteínas Fúngicas/genética , Genes Fúngicos , Haploidia , Proteínas de Choque Térmico/genética , Temperatura Alta , Concentração de Íons de Hidrogênio , Modelos Genéticos , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Temperatura
20.
RNA ; 17(12): 2249-55, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22025736

RESUMO

Protein localization within cells can be achieved by the targeting and localized translation of mRNA. Yet, our understanding of the dynamics of mRNA targeting and protein localization, and of how general this phenomenon is, is not clear. Plasmid-based expression systems have been used to visualize exogenously expressed mRNAs and proteins; however, these methods typically produce them at levels greater than endogenous and can result in mislocalization. Hence, a method that allows for the simultaneous visualization of endogenous mRNAs and their translation products in living cells is needed. We previously developed a method (m-TAG) to localize endogenously expressed mRNAs in yeast by chromosomal insertion of the MS2 aptamer sequence between the open-reading frame (ORF) and 3' UTR of any gene. Upon coexpression with the MS2 RNA-binding coat protein (MS2-CP) fused with GFP, the aptamer-tagged mRNAs bearing their 3' UTRs are localized using fluorescence microscopy. Here we describe an advanced method (mp-TAG) that allows for the simultaneous visualization of both endogenously expressed mRNAs and their translation products in living yeast for the first time. Homologous recombination is used to insert the mCherry gene and MS2-CP binding sites downstream from any ORF, in order to localize protein and mRNA, respectively. As proof of the concept, we tagged ATP2 as a representative gene and demonstrated that endogenous ATP2 mRNA and protein localize to mitochondria, as shown previously. In addition, we demonstrate that tagged proteins like Hhf2, Vph1, and Yef3 localize to their expected subcellular location, while the localization of their mRNAs is revealed for the first time.


Assuntos
Proteínas Fúngicas/análise , Marcação de Genes/métodos , RNA Mensageiro/análise , Leveduras/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genoma Fúngico , Histonas/genética , Histonas/metabolismo , Recombinação Homóloga , Espaço Intracelular/genética , Espaço Intracelular/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Microscopia de Fluorescência , Mitocôndrias/genética , Mitocôndrias/metabolismo , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , Biossíntese de Proteínas , Transporte Proteico , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo , Transporte de RNA , RNA Mensageiro/metabolismo , Leveduras/metabolismo
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