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1.
PLoS Pathog ; 16(6): e1008555, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32579593

RESUMO

Exhaustion is a dysfunctional state of cytotoxic CD8+ T cells (CTL) observed in chronic infection and cancer. Current in vivo models of CTL exhaustion using chronic viral infections or cancer yield very few exhausted CTL, limiting the analysis that can be done on these cells. Establishing an in vitro system that rapidly induces CTL exhaustion would therefore greatly facilitate the study of this phenotype, identify the truly exhaustion-associated changes and allow the testing of novel approaches to reverse or prevent exhaustion. Here we show that repeat stimulation of purified TCR transgenic OT-I CTL with their specific peptide induces all the functional (reduced cytokine production and polyfunctionality, decreased in vivo expansion capacity) and phenotypic (increased inhibitory receptors expression and transcription factor changes) characteristics of exhaustion. Importantly, in vitro exhausted cells shared the transcriptomic characteristics of the gold standard of exhaustion, CTL from LCMV cl13 infections. Gene expression of both in vitro and in vivo exhausted CTL was distinct from T cell anergy. Using this system, we show that Tcf7 promoter DNA methylation contributes to TCF1 downregulation in exhausted CTL. Thus this novel in vitro system can be used to identify genes and signaling pathways involved in exhaustion and will facilitate the screening of reagents that prevent/reverse CTL exhaustion.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Metilação de DNA/imunologia , Fator 1-alfa Nuclear de Hepatócito/imunologia , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Regiões Promotoras Genéticas/imunologia , Animais , Linfócitos T CD8-Positivos/patologia , Fator 1-alfa Nuclear de Hepatócito/genética , Coriomeningite Linfocítica/genética , Coriomeningite Linfocítica/patologia , Vírus da Coriomeningite Linfocítica/genética , Camundongos , Camundongos Transgênicos , Transdução de Sinais/genética , Transdução de Sinais/imunologia
2.
Nucleic Acids Res ; 48(11): 5873-5890, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32392347

RESUMO

The chromatin organizer SATB1 is highly enriched in thymocytes and is essential for T-cell development. Although SATB1 regulates a large number of genes important for T-cell development, the mechanism(s) regulating expression of SATB1 during this process remain elusive. Using chromatin immune precipitation-seq-based occupancy profiles of H3K4me3 and H3Kme1 at Satb1 gene locus, we predicted four different alternative promoters of Satb1 in mouse thymocytes and characterized them. The expression of Satb1 transcript variants with distinct 5' UTRs occurs in a stage-specific manner during T-cell development and is dependent on TCR signaling. The observed discrepancy between the expression levels of SATB1 mRNA and protein in developing thymocytes can be explained by the differential translatability of Satb1 transcript variants as confirmed by polysome profiling and in vitro translation assay. We show that Satb1 alternative promoters exhibit lineage-specific chromatin accessibility during T-cell development from progenitors. Furthermore, TCF1 regulates the Satb1 P2 promoter switch during CD4SP development, via direct binding to the Satb1 P2 promoter. CD4SP T cells from TCF1 KO mice exhibit downregulation of P2 transcript variant expression as well as low levels of SATB1 protein. Collectively, these results provide unequivocal evidence toward alternative promoter switch-mediated developmental stage-specific regulation of SATB1 in thymocytes.


Assuntos
Cromatina/metabolismo , Proteínas de Ligação à Região de Interação com a Matriz/genética , Regiões Promotoras Genéticas , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo , Animais , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular , Linhagem da Célula , Cromatina/genética , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Timócitos/citologia , Timócitos/metabolismo
3.
BMC Med Genet ; 21(1): 91, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32375679

RESUMO

BACKGROUND: Renal hypouricemia (RHUC) is a hereditary disorder where mutations in SLC22A12 gene and SLC2A9 gene cause RHUC type 1 (RHUC1) and RHUC type 2 (RHUC2), respectively. These genes regulate renal tubular reabsorption of urates while there exist other genes counterbalancing the net excretion of urates including ABCG2 and SLC17A1. Urate metabolism is tightly interconnected with glucose metabolism, and SLC2A9 gene may be involved in insulin secretion from pancreatic ß-cells. On the other hand, a myriad of genes are responsible for the impaired insulin secretion independently of urate metabolism. CASE PRESENTATION: We describe a 67 year-old Japanese man who manifested severe hypouricemia (0.7 mg/dl (3.8-7.0 mg/dl), 41.6 µmol/l (226-416 µmol/l)) and diabetes with impaired insulin secretion. His high urinary fractional excretion of urate (65.5%) and low urinary C-peptide excretion (25.7 µg/day) were compatible with the diagnosis of RHUC and impaired insulin secretion, respectively. Considering the fact that metabolic pathways regulating urates and glucose are closely interconnected, we attempted to delineate the genetic basis of the hypouricemia and the insulin secretion defect observed in this patient using whole exome sequencing. Intriguingly, we found homozygous Trp258* mutations in SLC22A12 gene causing RHUC1 while concurrent mutations reported to be associated with hyperuricemia were also discovered including ABCG2 (Gln141Lys) and SLC17A1 (Thr269Ile). SLC2A9, that also facilitates glucose transport, has been implicated to enhance insulin secretion, however, the non-synonymous mutations found in SLC2A9 gene of this patient were not dysfunctional variants. Therefore, we embarked on a search for causal mutations for his impaired insulin secretion, resulting in identification of multiple mutations in HNF1A gene (MODY3) as well as other genes that play roles in pancreatic ß-cells. Among them, the Leu80fs in the homeobox gene NKX6.1 was an unreported mutation. CONCLUSION: We found a case of RHUC1 carrying mutations in SLC22A12 gene accompanied with compensatory mutations associated with hyperuricemia, representing the first report showing coexistence of the mutations with opposed potential to regulate urate concentrations. On the other hand, independent gene mutations may be responsible for his impaired insulin secretion, which contains novel mutations in key genes in the pancreatic ß-cell functions that deserve further scrutiny.


Assuntos
Complicações do Diabetes/genética , Proteínas Facilitadoras de Transporte de Glucose/genética , Transportadores de Ânions Orgânicos/genética , Proteínas de Transporte de Cátions Orgânicos/genética , Erros Inatos do Transporte Tubular Renal/genética , Cálculos Urinários/genética , Idoso , Complicações do Diabetes/complicações , Complicações do Diabetes/patologia , Glucose/metabolismo , Fator 1-alfa Nuclear de Hepatócito/genética , Heterozigoto , Proteínas de Homeodomínio/genética , Homozigoto , Humanos , Insulina/biossíntese , Insulina/genética , Secreção de Insulina/genética , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Masculino , Mutação/genética , Erros Inatos do Transporte Tubular Renal/complicações , Erros Inatos do Transporte Tubular Renal/patologia , Ácido Úrico/metabolismo , Cálculos Urinários/complicações , Cálculos Urinários/patologia , Sequenciamento Completo do Exoma
4.
Proc Natl Acad Sci U S A ; 117(22): 12182-12191, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32414917

RESUMO

In multicellular organisms, paralogs from gene duplication survive purifying selection by evolving tissue-specific expression and function. Whether this genetic redundancy is also selected for within a single cell type is unclear for multimember paralogs, as exemplified by the four obligatory Lef/Tcf transcription factors of canonical Wnt signaling, mainly due to the complex genetics involved. Using the developing mouse lung as a model system, we generate two quadruple conditional knockouts, four triple mutants, and various combinations of double mutants, showing that the four Lef/Tcf genes function redundantly in the presence of at least two Lef/Tcf paralogs, but additively upon losing additional paralogs to specify and maintain lung epithelial progenitors. Prelung-specification, pan-epithelial double knockouts have no lung phenotype; triple knockouts have varying phenotypes, including defective branching and tracheoesophageal fistulas; and the quadruple knockout barely forms a lung, resembling the Ctnnb1 mutant. Postlung-specification deletion of all four Lef/Tcf genes leads to branching defects, down-regulation of progenitor genes, premature alveolar differentiation, and derepression of gastrointestinal genes, again phenocopying the corresponding Ctnnb1 mutant. Our study supports a monotonic, positive signaling relationship between CTNNB1 and Lef/Tcf in lung epithelial progenitors as opposed to reported repressor functions of Lef/Tcf, and represents a thorough in vivo analysis of cell-type-specific genetic redundancy among the four Lef/Tcf paralogs.


Assuntos
Embrião de Mamíferos/metabolismo , Células-Tronco Embrionárias/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Pulmão/metabolismo , Fator 1 de Ligação ao Facilitador Linfoide/fisiologia , Células-Tronco/metabolismo , beta Catenina/metabolismo , Animais , Diferenciação Celular , Embrião de Mamíferos/citologia , Células-Tronco Embrionárias/citologia , Feminino , Fator 1-alfa Nuclear de Hepatócito/fisiologia , Pulmão/citologia , Camundongos , Camundongos Knockout , Análise de Célula Única , Células-Tronco/citologia , Proteína 1 Semelhante ao Fator 7 de Transcrição/fisiologia , Proteína 2 Semelhante ao Fator 7 de Transcrição/fisiologia , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , beta Catenina/genética
5.
Nat Commun ; 11(1): 1393, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170132

RESUMO

Predicting drug-induced liver injury in a preclinical setting remains challenging, as cultured primary human hepatocytes (PHHs), pluripotent stem cell-derived hepatocyte-like cells (HLCs), and hepatoma cells exhibit poor drug biotransformation capacity. We here demonstrate that hepatic functionality depends more on cellular metabolism and extracellular nutrients than on developmental regulators. Specifically, we demonstrate that increasing extracellular amino acids beyond the nutritional need of HLCs and HepG2 cells induces glucose independence, mitochondrial function, and the acquisition of a transcriptional profile that is closer to PHHs. Moreover, we show that these high levels of amino acids are sufficient to drive HLC and HepG2 drug biotransformation and liver-toxin sensitivity to levels similar to those in PHHs. In conclusion, we provide data indicating that extracellular nutrient levels represent a major determinant of cellular maturity and can be utilized to guide stem cell differentiation to the hepatic lineage.


Assuntos
Aminoácidos/metabolismo , Carcinoma Hepatocelular/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Hepatócitos/metabolismo , Neoplasias Hepáticas/metabolismo , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Citocromo P-450 CYP3A , Feminino , Técnicas de Inativação de Genes , Células Hep G2 , Fator 1-alfa Nuclear de Hepatócito , Fator 3-gama Nuclear de Hepatócito , Ensaios de Triagem em Larga Escala , Proteínas de Homeodomínio , Humanos , Fígado , Masculino , Engenharia Metabólica , Redes e Vias Metabólicas , Pessoa de Meia-Idade , Células-Tronco Pluripotentes , Células-Tronco , Transcriptoma , Proteínas Supressoras de Tumor
6.
Arch Endocrinol Metab ; 64(1): 17-23, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31576961

RESUMO

Objective We aimed to identify the frequency of monogenic diabetes, which is poorly studied in multiethnic populations, due to GCK or HNF1A mutations in patients with suggestive clinical characteristics from the Brazilian population, as well as investigate if the MODY probability calculator (MPC) could help patients with their selection. Subjects and methods Inclusion criteria were patients with DM diagnosed before 35 years; body mass index < 30 kg/m2; negative autoantibodies; and family history of DM in two or more generations. We sequenced HNF1A in 27 patients and GCK in seven subjects with asymptomatic mild fasting hyperglycemia. In addition, we calculated MODY probability with MPC. Results We identified 11 mutations in 34 patients (32.3%). We found three novel mutations. In the GCK group, six cases had mutations (85.7%), and their MODY probability on MPC was higher than 50%. In the HNF1A group, five of 27 individuals had mutations (18.5%). The MPC was higher than 75% in 11 subjects (including all five cases with HNF1A mutations). Conclusion Approximately one third of the studied patients have GCK or HNF1A mutations. Inclusion criteria included efficiency in detecting patients with GCK mutations but not for HNF1A mutations (< 20%). MPC was helpful in narrowing the number of candidates for HNF1A screening.


Assuntos
Diabetes Mellitus Tipo 2/genética , Glucoquinase/genética , Fator 1-alfa Nuclear de Hepatócito/genética , Mutação/genética , Adolescente , Adulto , Brasil , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Linhagem , Fenótipo , Probabilidade , Adulto Jovem
7.
Immunity ; 51(6): 1043-1058.e4, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31810882

RESUMO

T cell dysfunction is a characteristic feature of chronic viral infection and cancer. Recent studies in chronic lymphocytic choriomeningitis virus (LCMV) infection have defined a PD-1+ Tcf-1+ CD8+ T cell subset capable of self-renewal and differentiation into more terminally differentiated cells that downregulate Tcf-1 and express additional inhibitory molecules such as Tim3. Here, we demonstrated that expression of the glycoprotein CD101 divides this terminally differentiated population into two subsets. Stem-like Tcf-1+ CD8+ T cells initially differentiated into a transitory population of CD101-Tim3+ cells that later converted into CD101+ Tim3+ cells. Recently generated CD101-Tim3+ cells proliferated in vivo, contributed to viral control, and were marked by an effector-like transcriptional signature including expression of the chemokine receptor CX3CR1, pro-inflammatory cytokines, and granzyme B. PD-1 pathway blockade increased the numbers of CD101-Tim3+ CD8+ T cells, suggesting that these newly generated transitional cells play a critical role in PD-1-based immunotherapy.


Assuntos
Antígenos CD/metabolismo , Linfócitos T CD8-Positivos/imunologia , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Animais , Biomarcadores/metabolismo , Receptor 1 de Quimiocina CX3C/genética , Receptor 1 de Quimiocina CX3C/metabolismo , Feminino , Granzimas/genética , Granzimas/metabolismo , Receptor Celular 2 do Vírus da Hepatite A/biossíntese , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Coriomeningite Linfocítica/virologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/genética
8.
Medicine (Baltimore) ; 98(49): e18264, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31804362

RESUMO

BACKGROUND: LncRNA HNF1A Antisense RNA 1 (HNF1A-AS1) is often dysregulated in cancer. We performed this meta-analysis to clarify the usefulness of HNF1A-AS1 as a prognostic marker in malignant tumors. METHODS: The PubMed, OVID, and Web of Science databases were searched from inception to January 11, 2018. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to explore the relationship between HNF1A-AS1 expression and survival. Odds ratios (OR) were calculated to assess the association between HNF1A-AS1 expression and pathological parameters. RESULTS: Eight studies with a total of 802 patients were included in the study. The pooled hazard ratio (HR) suggested high HNF1A-AS1 expression correlated with poor overall survival (OS) (HR = 4.85, 95% confidence interval (CI): 2.43-9.68), and disease-free survival (DFS) (HR = 6.34, 95% CI: 1.03-39.12) in cancer patients. High HNF1A-AS1 expression also correlated with poor histological grade (OR = 1.88, 95% CI: 1.27-2.79), high tumor stage (OR = 4.04, 95% CI: 2.53-6.47), lymph node metastasis (LNM) (OR = 4.53, 95% CI: 2.30-8.92), and distant metastasis (OR = 5.99, 95% CI: 2.88-12.48). Begg funnel plot did not show any evidence of obvious asymmetry for high tumor stage (Pr > |z| = 0.368) and LNM (Pr > |z| = 1.000). CONCLUSIONS: Thus high HNF1A-AS1 expression is predictive of poor OS, DFS, lymph node metastasis, distant metastasis, histological grade, and larger tumor stage, which suggests high HNF1A-AS1 expression may serve as a novel biomarker of poor prognosis in cancer.


Assuntos
Biomarcadores Tumorais/genética , Fator 1-alfa Nuclear de Hepatócito/genética , Neoplasias/genética , RNA Longo não Codificante , Humanos , Prognóstico
9.
Int J Mol Sci ; 20(24)2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31835596

RESUMO

Osteoporosis, a disease characterized by both loss of bone mass and structural deterioration of bone, is the most common reason for a broken bone among the elderly. It is known that the attenuated differentiation ability of osteogenic cells has been regarded as one of the greatest contributors to age-related bone formation reduction. However, the effects of current therapies are still unsatisfactory. In this study we identify a novel long noncoding RNA AK045490 which is correlated with osteogenic differentiation and enriched in skeletal tissues of mice. In vitro analysis of bone-derived mesenchymal stem cells (BMSCs) showed that AK045490 inhibited osteoblast differentiation. In vivo inhibition of AK045490 by its small interfering RNA rescued bone formation in ovariectomized osteoporosis mice model. Mechanistically, AK045490 inhibited the nuclear translocation of ß-catenin and downregulated the expression of TCF1, LEF1, and Runx2. The results suggest that Lnc-AK045490 suppresses ß-catenin/TCF1/Runx2 signaling and inhibits osteoblast differentiation and bone formation, providing a novel mechanism of osteogenic differentiation and a potential drug target for osteoporosis.


Assuntos
Células-Tronco Mesenquimais/citologia , Osteoporose/tratamento farmacológico , RNA Longo não Codificante/genética , RNA Interferente Pequeno/administração & dosagem , Transdução de Sinais , Animais , Diferenciação Celular , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Modelos Animais de Doenças , Feminino , Fator 1-alfa Nuclear de Hepatócito/genética , Células-Tronco Mesenquimais/metabolismo , Camundongos , Osteogênese , Osteoporose/genética , Osteoporose/metabolismo , RNA Longo não Codificante/antagonistas & inibidores , RNA Interferente Pequeno/farmacologia , beta Catenina/metabolismo
10.
Nature ; 576(7787): 465-470, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31827286

RESUMO

Tumour-infiltrating lymphocytes are associated with a survival benefit in several tumour types and with the response to immunotherapy1-8. However, the reason some tumours have high CD8 T cell infiltration while others do not remains unclear. Here we investigate the requirements for maintaining a CD8 T cell response against human cancer. We find that CD8 T cells within tumours consist of distinct populations of terminally differentiated and stem-like cells. On proliferation, stem-like CD8 T cells give rise to more terminally differentiated, effector-molecule-expressing daughter cells. For many T cells to infiltrate the tumour, it is critical that this effector differentiation process occur. In addition, we show that these stem-like T cells reside in dense antigen-presenting-cell niches within the tumour, and that tumours that fail to form these structures are not extensively infiltrated by T cells. Patients with progressive disease lack these immune niches, suggesting that niche breakdown may be a key mechanism of immune escape.


Assuntos
Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular , Linfócitos do Interstício Tumoral/citologia , Linfócitos do Interstício Tumoral/imunologia , Neoplasias/imunologia , Células-Tronco/citologia , Animais , Apresentação do Antígeno/genética , Apresentação do Antígeno/imunologia , Linfócitos T CD8-Positivos/metabolismo , Progressão da Doença , Epigênese Genética , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Humanos , Linfócitos do Interstício Tumoral/metabolismo , Camundongos , Neoplasias/patologia , Nicho de Células-Tronco/imunologia , Transcrição Genética , Evasão Tumoral/genética , Evasão Tumoral/imunologia
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(5): 1463-1468, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31607299

RESUMO

OBJECTIVE: To investigate the transcriptional regulation of transcription factor MZF-1 on acute monocytic leukemia-related gene MLAA-34. METHODS: The effect of MZF-1 on the transcriptional activity of MLAA-34 gene promoter was analyzed by luciferase reporter gene detection system and site-directed mutation technique. The EMSA and ChIP assay were used to verify whether MZF-1 directly and specifically binds to the core region of MLAA-34 promoter. The over-expression vector and interference vector of MZF-1 were constructed to transfect U937 cells, and RT-PCR and Western blot were used to detect the transcription and expression changes of MLAA-34 gene. RESULTS: The transcription factor MZF-1 had a regulatory effect on MLAA-34 gene expression, and the relative luciferase activity was decreased after MZF-1 binding point mutation (P<0.01). EMSA and ChIP experiments demonstrated that MZF-1 could directly bind to MLAA-34 promoter and play a regulatory role. In the over-expression test, the increase of MZF-1 could up-regulate the expression of MLAA-34 (P<0.05). In the interference test, the decrease of MZF-1 could down-regulate the expression of MLAA-34 (P<0.05). CONCLUSION: Transcription factor MZF-1 can bind to the transcriptional regulatory region on the promoter of MLAA-34 gene and promote the transcription of MLAA-34 gene in acute monocytic leukemia.


Assuntos
Antígenos de Neoplasias/genética , Proteínas Reguladoras de Apoptose/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Leucemia Monocítica Aguda , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Fator 1-alfa Nuclear de Hepatócito , Humanos , Regiões Promotoras Genéticas , Transcrição Genética
12.
Exp Suppl ; 111: 385-416, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31588541

RESUMO

In addition to the common types of diabetes mellitus, two major monogenic diabetes forms exist. Maturity-onset diabetes of the young (MODY) represents a heterogenous group of monogenic, autosomal dominant diseases. MODY accounts for 1-2% of all diabetes cases, and it is not just underdiagnosed but often misdiagnosed to type 1 or type 2 diabetes. More than a dozen MODY genes have been identified to date, and their molecular classification is of great importance in the correct treatment decision and in the judgment of the prognosis. The most prevalent subtypes are HNF1A, GCK, and HNF4A. Genetic testing for MODY has changed recently due to the technological advancements, as contrary to the sequential testing performed in the past, nowadays all MODY genes can be tested simultaneously by next-generation sequencing. The other major group of monogenic diabetes is neonatal diabetes mellitus which can be transient or permanent, and often the diabetes is a part of a syndrome. It is a severe monogenic disease appearing in the first 6 months of life. The hyperglycemia usually requires insulin. There are two forms, permanent neonatal diabetes mellitus (PNDM) and transient neonatal diabetes mellitus (TNDM). In TNDM, the diabetes usually reverts within several months but might relapse later in life. The incidence of NDM is 1:100,000-1:400,000 live births, and PNDM accounts for half of the cases. Most commonly, neonatal diabetes is caused by mutations in KCNJ11 and ABCC8 genes encoding the ATP-dependent potassium channel of the ß cell. Neonatal diabetes has experienced a quick and successful transition into the clinical practice since the discovery of the molecular background. In case of both genetic diabetes groups, recent guidelines recommend genetic testing.


Assuntos
Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus/genética , Doenças do Recém-Nascido/genética , Testes Genéticos , Quinases do Centro Germinativo , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/genética , Humanos , Recém-Nascido , Mutação , Canais de Potássio Corretores do Fluxo de Internalização/genética , Proteínas Serina-Treonina Quinases/genética , Receptores Sulfonilureia/genética
13.
Nat Rev Immunol ; 19(11): 665-674, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31570879

RESUMO

'T cell exhaustion' is a broad term that has been used to describe the response of T cells to chronic antigen stimulation, first in the setting of chronic viral infection but more recently in response to tumours. Understanding the features of and pathways to exhaustion has crucial implications for the success of checkpoint blockade and adoptive T cell transfer therapies. In this Viewpoint article, 18 experts in the field tell us what exhaustion means to them, ranging from complete lack of effector function to altered functionality to prevent immunopathology, with potential differences between cancer and chronic infection. Their responses highlight the dichotomy between terminally differentiated exhausted T cells that are TCF1- and the self-renewing TCF1+ population from which they derive. These TCF1+ cells are considered by some to have stem cell-like properties akin to memory T cell populations, but the developmental relationships are unclear at present. Recent studies have also highlighted an important role for the transcriptional regulator TOX in driving the epigenetic enforcement of exhaustion, but key questions remain about the potential to reverse the epigenetic programme of exhaustion and how this might affect the persistence of T cell populations.


Assuntos
Linfócitos T/imunologia , Animais , Fator 1-alfa Nuclear de Hepatócito/fisiologia , Proteínas de Grupo de Alta Mobilidade/fisiologia , Humanos , Infecções/imunologia , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/fisiologia
14.
Nat Genet ; 51(10): 1459-1474, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31578528

RESUMO

Elevated serum urate levels cause gout and correlate with cardiometabolic diseases via poorly understood mechanisms. We performed a trans-ancestry genome-wide association study of serum urate in 457,690 individuals, identifying 183 loci (147 previously unknown) that improve the prediction of gout in an independent cohort of 334,880 individuals. Serum urate showed significant genetic correlations with many cardiometabolic traits, with genetic causality analyses supporting a substantial role for pleiotropy. Enrichment analysis, fine-mapping of urate-associated loci and colocalization with gene expression in 47 tissues implicated the kidney and liver as the main target organs and prioritized potentially causal genes and variants, including the transcriptional master regulators in the liver and kidney, HNF1A and HNF4A. Experimental validation showed that HNF4A transactivated the promoter of ABCG2, encoding a major urate transporter, in kidney cells, and that HNF4A p.Thr139Ile is a functional variant. Transcriptional coregulation within and across organs may be a general mechanism underlying the observed pleiotropy between urate and cardiometabolic traits.


Assuntos
Doenças Cardiovasculares/sangue , Marcadores Genéticos , Gota/sangue , Doenças Metabólicas/sangue , Polimorfismo de Nucleotídeo Único , Transdução de Sinais , Ácido Úrico/sangue , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/genética , Estudos de Coortes , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Gota/epidemiologia , Gota/genética , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/genética , Humanos , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Fígado/patologia , Doenças Metabólicas/epidemiologia , Doenças Metabólicas/genética , Proteínas de Neoplasias/genética , Especificidade de Órgãos
15.
Inflamm Res ; 68(12): 1025-1034, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31531682

RESUMO

OBJECTIVE: Saikosaponin c (SSc), a compound purified from the traditional Chinese herb of Radix Bupleuri was previously identified to exhibit anti-HBV replication activity. However, the mechanism through which SSc acts against HBV remains unknown. In this study, we investigated the mechanism of SSc mediated anti-HBV activity. METHODS: HepG2.2.15 cells were cultured at 37 â„ƒ in the presence of 1-40 µg/mL of SSc or DMSO as a control. The expression profile of HBV markers, cytokines, HNF1α and HNF4α were investigated by real-time quantitative PCR, Elisa, Western blot and Dot blotting. Knockdown of HNF1α or HNF4α in HepG2.2.15 cells was mediated by two small siRNAs specifically targeting HNF1α or HNF4α. RESULTS: We found that SSc stimulates IL-6 expression, leading to attenuated HNF1α and HNF4α expression, which further mediates suppression of HBV pgRNA synthesis. Knockdown of HNF1α or HNF4α in HepG2.2.15 cells by RNA interference abrogates SSc's anti-HBV role. Moreover, SSc is effective to both wild-type and drug-resistant HBV mutants. CONCLUSION: SSc inhibits pgRNA synthesis by targeting HNF1α and HNF4α. These results indicate that SSc acts as a promising compound for modulating pgRNA transcription in the therapeutic strategies against HBV infection.


Assuntos
Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Fator 4 Nuclear de Hepatócito/metabolismo , Ácido Oleanólico/análogos & derivados , RNA Viral/biossíntese , RNA/biossíntese , Saponinas/farmacologia , Células Hep G2 , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/metabolismo , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/genética , Humanos , Ácido Oleanólico/farmacologia , Interferência de RNA , RNA Interferente Pequeno/genética
16.
Proc Natl Acad Sci U S A ; 116(40): 20070-20076, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31530725

RESUMO

T cell maintenance in chronic infection and cancer follows a hierarchical order. Short-lived effector CD8 T cells are constitutively replaced from a proliferation-competent Tcf1-expressing progenitor population. This occurs spontaneously at low levels and increases in magnitude upon blocking PD-1 signaling. We explore how CD4 T cell help controls transition and survival of the progenitors and their progeny by utilizing single-cell RNA sequencing. Unexpectedly, absence of CD4 help caused reductions in cell numbers only among terminally differentiated cells while proliferation-competent progenitor cells remained unaffected with regard to their numbers and their overall phenotype. In fact, upon restoration of a functional CD4 compartment, the progenitors began to regenerate the effector CD8 T cells. Thus, unlike memory T cells for which secondary expansion requires CD4 T cell help, this is not a necessity for proliferation-competent progenitor cells in dysfunctional populations. Our data therefore reveals that proliferation-competent cells in dysfunctional populations show a previously unrecognized uncoupling of CD4 T cell help that is otherwise required by conventional memory T cells.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Ativação Linfocitária/imunologia , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Diferenciação Celular/imunologia , Movimento Celular , Proliferação de Células , Células Cultivadas , Epitopos de Linfócito T/imunologia , Camundongos , Camundongos Transgênicos , Fenótipo , Transdução de Sinais
17.
Endocr Regul ; 53(2): 110-134, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31517624

RESUMO

MODY (Maturity Onset Diabetes of the Young) is a type of diabetes resulting from a pathogenic effect of gene mutations. Up to date, 13 MODY genes are known. Gene HNF1A is one of the most common causes of MODY diabetes (HNF1A-MODY; MODY3). This gene is polymorphic and more than 1200 pathogenic and non-pathogenic HNF1A variants were described in its UTRs, exons and introns. For HNF1A-MODY, not just gene but also phenotype heterogeneity is typical. Although there are some clinical instructions, HNF1A-MODY patients often do not meet every diagnostic criteria or they are still misdiagnosed as type 1 and type 2 diabetics. There is a constant effort to find suitable biomarkers to help with in distinguishing of MODY3 from Type 1 Diabetes (T1D) and Type 2 Diabetes (T2D). DNA sequencing is still necessary for unambiguous confirmation of clinical suspicion of MODY. NGS (Next Generation Sequencing) methods brought discoveries of multiple new gene variants and new instructions for their pathogenicity classification were required. The most actual problem is classification of variants with uncertain significance (VUS) which is a stumbling-block for clinical interpretation. Since MODY is a hereditary disease, DNA analysis of family members is helpful or even crucial. This review is updated summary about HNF1A-MODY genetics, pathophysiology, clinics functional studies and variant classification.


Assuntos
Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/terapia , Fator 1-alfa Nuclear de Hepatócito/genética , Mutação , Biomarcadores/análise , Análise Mutacional de DNA , Diabetes Mellitus Tipo 2/classificação , Diagnóstico Diferencial , Humanos , Fenótipo
18.
Environ Toxicol ; 34(12): 1313-1319, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31423742

RESUMO

Syzygium cumini (Myrtaceae) is commonly called as Jamun or Jambolan. It has antidiabetic, anti-inflammatory, antipyretic, and antioxidant activities. Hepatocellular carcinoma is the most frequent and deadliest cancers worldwide. We investigated the cytotoxic potentials of S. cumini methanolic seed kernel extract against human hepatoma HepG2 cells. HepG2 cells were treated with 10, 20, and 40 µg/mL of seed kernel extract for 24 hours and cytotoxic analysis was performed by MTT assay. S. cumini induced apoptosis related morphological changes in HepG2 cells were analyzed by annexin V and propidium iodide double staining. Nuclear fragmentation and chromatin condensation were analyzed by Hoechst nuclear staining. Mitochondrial membrane potential (MMP) was investigated by 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolyl-carbocyanine iodide (JC-1) staining. Protein expressions of hepatocyte nuclear factor-1α (HFN-1α) was performed using western blotting. S. cumini treatments caused a significant and a concentration-dependent increase in the cytotoxicity of HepG2 cells. S. cumini treatments increased the percentage of cells in an early and late apoptosis stage. This treatment also caused chromatin condensation and nuclear fragmentation. Further, S. cumini treatments decreased MMP and also caused a significant downregulation of HFN-1α protein expression. The present study demonstrated that S. cumini seed extract induced apoptosis in HepG2 cells through decrease in MMP and downregulation of HFN-1α.


Assuntos
Apoptose/efeitos dos fármacos , Myrtaceae/química , Extratos Vegetais/farmacologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Regulação para Baixo/efeitos dos fármacos , Células Hep G2 , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Metanol/química , Myrtaceae/metabolismo , Extratos Vegetais/análise , Extratos Vegetais/química , Sementes/química , Sementes/metabolismo
19.
Nucleic Acids Res ; 47(18): 9637-9657, 2019 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-31410472

RESUMO

Establishing causal relationship between epigenetic marks and gene transcription requires molecular tools, which can precisely modify specific genomic regions. Here, we present a modular and extensible CRISPR/dCas9-based toolbox for epigenetic editing and direct gene regulation. It features a system for expression of orthogonal dCas9 proteins fused to various effector domains and includes a multi-gRNA system for simultaneous targeting dCas9 orthologs to up to six loci. The C- and N-terminal dCas9 fusions with DNMT3A and TET1 catalytic domains were thoroughly characterized. We demonstrated simultaneous use of the DNMT3A-dSpCas9 and TET1-dSaCas9 fusions within the same cells and showed that imposed cytosine hyper- and hypo-methylation altered level of gene transcription if targeted CpG sites were functionally relevant. Dual epigenetic manipulation of the HNF1A and MGAT3 genes, involved in protein N-glycosylation, resulted in change of the glycan phenotype in BG1 cells. Furthermore, simultaneous targeting of the TET1-dSaCas9 and VPR-dSpCas9 fusions to the HNF1A regulatory region revealed strong and persistent synergistic effect on gene transcription, up to 30 days following cell transfection, suggesting involvement of epigenetic mechanisms in maintenance of the reactivated state. Also, modulation of dCas9 expression effectively reduced off-target effects while maintaining the desired effects on target regions.


Assuntos
Sistemas CRISPR-Cas/genética , Epigênese Genética , Edição de Genes/métodos , Transcrição Genética , Aciltransferases/genética , Domínio Catalítico/genética , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA/genética , Regulação da Expressão Gênica/genética , Genoma/genética , Glicosilação , Fator 1-alfa Nuclear de Hepatócito/genética , Humanos , Oxigenases de Função Mista/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/genética , RNA Guia/genética
20.
Nat Immunol ; 20(9): 1150-1160, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31358996

RESUMO

Innate lymphoid cells (ILCs) play important functions in immunity and tissue homeostasis, but their development is poorly understood. Through the use of single-cell approaches, we examined the transcriptional and functional heterogeneity of ILC progenitors, and studied the precursor-product relationships that link the subsets identified. This analysis identified two successive stages of ILC development within T cell factor 1-positive (TCF-1+) early innate lymphoid progenitors (EILPs), which we named 'specified EILPs' and 'committed EILPs'. Specified EILPs generated dendritic cells, whereas this potential was greatly decreased in committed EILPs. TCF-1 was dispensable for the generation of specified EILPs, but required for the generation of committed EILPs. TCF-1 used a pre-existing regulatory landscape established in upstream lymphoid precursors to bind chromatin in EILPs. Our results provide insight into the mechanisms by which TCF-1 promotes developmental progression of ILC precursors, while constraining their dendritic cell lineage potential and enforcing commitment to ILC fate.


Assuntos
Linhagem da Célula/imunologia , Células Dendríticas/citologia , Fator 1-alfa Nuclear de Hepatócito/imunologia , Células Progenitoras Linfoides/citologia , Linfócitos T/citologia , Animais , Diferenciação Celular/imunologia , Células Cultivadas , Regulação da Expressão Gênica/genética , Fator 1-alfa Nuclear de Hepatócito/genética , Camundongos , Camundongos Endogâmicos C57BL , Transcrição Genética/genética
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