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1.
Acta Neuropathol ; 139(2): 365-382, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31552482

RESUMO

Oligodendrocyte progenitor cells (OPCs) account for about 5% of total brain and spinal cord cells, giving rise to myelinating oligodendrocytes that provide electrical insulation to neurons of the CNS. OPCs have also recently been shown to regulate inflammatory responses and glial scar formation, suggesting functions that extend beyond myelination. Low-density lipoprotein receptor-related protein 1 (LRP1) is a multifaceted phagocytic receptor that is highly expressed in several CNS cell types, including OPCs. Here, we have generated an oligodendroglia-specific knockout of LRP1, which presents with normal myelin development, but is associated with better outcomes in two animal models of demyelination (EAE and cuprizone). At a mechanistic level, LRP1 did not directly affect OPC differentiation into mature oligodendrocytes. Instead, animals lacking LRP1 in OPCs in the demyelinating CNS were characterized by a robust dampening of inflammation. In particular, LRP1-deficient OPCs presented with impaired antigen cross-presentation machinery, suggesting a failure to propagate the inflammatory response and thus promoting faster myelin repair and neuroprotection. Our study places OPCs as major regulators of neuroinflammation in an LRP1-dependent fashion.

2.
Nat Cell Biol ; 21(12): 1532-1543, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31792382

RESUMO

Apoptotic cell clearance (efferocytosis) elicits an anti-inflammatory response by phagocytes, but the mechanisms that underlie this response are still being defined. Here, we uncover a chloride-sensing signalling pathway that controls both the phagocyte 'appetite' and its anti-inflammatory response. Efferocytosis transcriptionally altered the genes that encode the solute carrier (SLC) proteins SLC12A2 and SLC12A4. Interfering with SLC12A2 expression or function resulted in a significant increase in apoptotic corpse uptake per phagocyte, whereas the loss of SLC12A4 inhibited corpse uptake. In SLC12A2-deficient phagocytes, the canonical anti-inflammatory program was replaced by pro-inflammatory and oxidative-stress-associated gene programs. This 'switch' to pro-inflammatory sensing of apoptotic cells resulted from the disruption of the chloride-sensing pathway (and not due to corpse overload or poor degradation), including the chloride-sensing kinases WNK1, OSR1 and SPAK-which function upstream of SLC12A2-had a similar effect on efferocytosis. Collectively, the WNK1-OSR1-SPAK-SLC12A2/SLC12A4 chloride-sensing pathway and chloride flux in phagocytes are key modifiers of the manner in which phagocytes interpret the engulfed apoptotic corpse.

3.
J Am Soc Nephrol ; 30(10): 2000-2016, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31537649

RESUMO

BACKGROUND: Although diabetic kidney disease demonstrates both familial clustering and single nucleotide polymorphism heritability, the specific genetic factors influencing risk remain largely unknown. METHODS: To identify genetic variants predisposing to diabetic kidney disease, we performed genome-wide association study (GWAS) analyses. Through collaboration with the Diabetes Nephropathy Collaborative Research Initiative, we assembled a large collection of type 1 diabetes cohorts with harmonized diabetic kidney disease phenotypes. We used a spectrum of ten diabetic kidney disease definitions based on albuminuria and renal function. RESULTS: Our GWAS meta-analysis included association results for up to 19,406 individuals of European descent with type 1 diabetes. We identified 16 genome-wide significant risk loci. The variant with the strongest association (rs55703767) is a common missense mutation in the collagen type IV alpha 3 chain (COL4A3) gene, which encodes a major structural component of the glomerular basement membrane (GBM). Mutations in COL4A3 are implicated in heritable nephropathies, including the progressive inherited nephropathy Alport syndrome. The rs55703767 minor allele (Asp326Tyr) is protective against several definitions of diabetic kidney disease, including albuminuria and ESKD, and demonstrated a significant association with GBM width; protective allele carriers had thinner GBM before any signs of kidney disease, and its effect was dependent on glycemia. Three other loci are in or near genes with known or suggestive involvement in this condition (BMP7) or renal biology (COLEC11 and DDR1). CONCLUSIONS: The 16 diabetic kidney disease-associated loci may provide novel insights into the pathogenesis of this condition and help identify potential biologic targets for prevention and treatment.

4.
Sci Rep ; 9(1): 4836, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30894605

RESUMO

Single-cell transcriptomic methods classify new and existing cell types very effectively, but alternative approaches are needed to quantify the individual regulatory states of cells in their native tissue context. We combined the tissue preservation and single-cell resolution of laser capture with an improved preamplification procedure enabling RNA sequencing of 10 microdissected cells. This in situ 10-cell RNA sequencing (10cRNA-seq) can exploit fluorescent reporters of cell type in genetically engineered mice and is compatible with freshly cryoembedded clinical biopsies from patients. Through recombinant RNA spike-ins, we estimate dropout-free technical reliability as low as ~250 copies and a 50% detection sensitivity of ~45 copies per 10-cell reaction. By using small pools of microdissected cells, 10cRNA-seq improves technical per-cell reliability and sensitivity beyond existing approaches for single-cell RNA sequencing (scRNA-seq). Detection of low-abundance transcripts by 10cRNA-seq is comparable to random 10-cell groups of scRNA-seq data, suggesting no loss of gene recovery when cells are isolated in situ. Combined with existing approaches to deconvolve small pools of cells, 10cRNA-seq offers a reliable, unbiased, and sensitive way to measure cell-state heterogeneity in tissues and tumors.

5.
Diabetes Care ; 42(3): 406-415, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30659077

RESUMO

OBJECTIVE: Genetic risk scores (GRS) have been developed that differentiate individuals with type 1 diabetes from those with other forms of diabetes and are starting to be used for population screening; however, most studies were conducted in European-ancestry populations. This study identifies novel genetic variants associated with type 1 diabetes risk in African-ancestry participants and develops an African-specific GRS. RESEARCH DESIGN AND METHODS: We generated single nucleotide polymorphism (SNP) data with the ImmunoChip on 1,021 African-ancestry participants with type 1 diabetes and 2,928 control participants. HLA class I and class II alleles were imputed using SNP2HLA. Logistic regression models were used to identify genome-wide significant (P < 5.0 × 10-8) SNPs associated with type 1 diabetes in the African-ancestry samples and validate SNPs associated with risk in known European-ancestry loci (P < 2.79 × 10-5). RESULTS: African-specific (HLA-DQA1*03:01-HLA-DQB1*02:01) and known European-ancestry HLA haplotypes (HLA-DRB1*03:01-HLA-DQA1*05:01-HLA-DQB1*02:01, HLA-DRB1*04:01-HLA-DQA1*03:01-HLA-DQB1*03:02) were significantly associated with type 1 diabetes risk. Among European-ancestry defined non-HLA risk loci, six risk loci were significantly associated with type 1 diabetes in subjects of African ancestry. An African-specific GRS provided strong prediction of type 1 diabetes risk (area under the curve 0.871), performing significantly better than a European-based GRS and two polygenic risk scores in independent discovery and validation cohorts. CONCLUSIONS: Genetic risk of type 1 diabetes includes ancestry-specific, disease-associated variants. The GRS developed here provides improved prediction of type 1 diabetes in African-ancestry subjects and a means to identify groups of individuals who would benefit from immune monitoring for early detection of islet autoimmunity.


Assuntos
Grupo com Ancestrais do Continente Africano/genética , Diabetes Mellitus Tipo 1/etnologia , Diabetes Mellitus Tipo 1/genética , Testes Genéticos , Antígenos HLA-D/genética , Grupo com Ancestrais do Continente Africano/estatística & dados numéricos , Alelos , Estudos de Casos e Controles , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Predisposição Genética para Doença , Testes Genéticos/métodos , Testes Genéticos/normas , Estudo de Associação Genômica Ampla , Cadeias alfa de HLA-DQ/genética , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Haplótipos , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Valor Preditivo dos Testes , Projetos de Pesquisa , Fatores de Risco
6.
Diabetes ; 68(4): 847-857, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30655385

RESUMO

The risk for autoimmunity and subsequently type 1 diabetes is 10-fold higher in children with a first-degree family history of type 1 diabetes (FDR children) than in children in the general population (GP children). We analyzed children with high-risk HLA genotypes (n = 4,573) in the longitudinal TEDDY birth cohort to determine how much of the divergent risk is attributable to genetic enrichment in affected families. Enrichment for susceptible genotypes of multiple type 1 diabetes-associated genes and a novel risk gene, BTNL2, was identified in FDR children compared with GP children. After correction for genetic enrichment, the risks in the FDR and GP children converged but were not identical for multiple islet autoantibodies (hazard ratio [HR] 2.26 [95% CI 1.6-3.02]) and for diabetes (HR 2.92 [95% CI 2.05-4.16]). Convergence varied depending upon the degree of genetic susceptibility. Risks were similar in the highest genetic susceptibility group for multiple islet autoantibodies (14.3% vs .12.7%) and diabetes (4.8% vs. 4.1%) and were up to 5.8-fold divergent for children in the lowest genetic susceptibility group, decreasing incrementally in GP children but not in FDR children. These findings suggest that additional factors enriched within affected families preferentially increase the risk of autoimmunity and type 1 diabetes in lower genetic susceptibility strata.


Assuntos
Autoimunidade/fisiologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Autoanticorpos/imunologia , Autoimunidade/genética , Predisposição Genética para Doença/genética , Genótipo , Antígenos HLA-DQ/genética , Antígenos HLA-DQ/imunologia , Humanos , Ilhotas Pancreáticas/metabolismo , Modelos de Riscos Proporcionais , Fatores de Risco
7.
Genome Med ; 10(1): 97, 2018 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-30572963

RESUMO

BACKGROUND: In recent years, research has consistently proven the occurrence of genetic overlap across autoimmune diseases, which supports the existence of common pathogenic mechanisms in autoimmunity. The objective of this study was to further investigate this shared genetic component. METHODS: For this purpose, we performed a cross-disease meta-analysis of Immunochip data from 37,159 patients diagnosed with a seropositive autoimmune disease (11,489 celiac disease (CeD), 15,523 rheumatoid arthritis (RA), 3477 systemic sclerosis (SSc), and 6670 type 1 diabetes (T1D)) and 22,308 healthy controls of European origin using the R package ASSET. RESULTS: We identified 38 risk variants shared by at least two of the conditions analyzed, five of which represent new pleiotropic loci in autoimmunity. We also identified six novel genome-wide associations for the diseases studied. Cell-specific functional annotations and biological pathway enrichment analyses suggested that pleiotropic variants may act by deregulating gene expression in different subsets of T cells, especially Th17 and regulatory T cells. Finally, drug repositioning analysis evidenced several drugs that could represent promising candidates for CeD, RA, SSc, and T1D treatment. CONCLUSIONS: In this study, we have been able to advance in the knowledge of the genetic overlap existing in autoimmunity, thus shedding light on common molecular mechanisms of disease and suggesting novel drug targets that could be explored for the treatment of the autoimmune diseases studied.


Assuntos
Doenças Autoimunes/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Artrite Reumatoide/genética , Doença Celíaca/genética , Diabetes Mellitus Tipo 1/genética , Estudo de Associação Genômica Ampla , Humanos , Anotação de Sequência Molecular , Escleroderma Sistêmico/genética
8.
Nature ; 563(7733): 714-718, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30464343

RESUMO

Development and routine tissue homeostasis require a high turnover of apoptotic cells. These cells are removed by professional and non-professional phagocytes via efferocytosis1. How a phagocyte maintains its homeostasis while coordinating corpse uptake, processing ingested materials and secreting anti-inflammatory mediators is incompletely understood1,2. Here, using RNA sequencing to characterize the transcriptional program of phagocytes actively engulfing apoptotic cells, we identify a genetic signature involving 33 members of the solute carrier (SLC) family of membrane transport proteins, in which expression is specifically modulated during efferocytosis, but not during antibody-mediated phagocytosis. We assessed the functional relevance of these SLCs in efferocytic phagocytes and observed a robust induction of an aerobic glycolysis program, initiated by SLC2A1-mediated glucose uptake, with concurrent suppression of the oxidative phosphorylation program. The different steps of phagocytosis2-that is, 'smell' ('find-me' signals or sensing factors released by apoptotic cells), 'taste' (phagocyte-apoptotic cell contact) and 'ingestion' (corpse internalization)-activated distinct and overlapping sets of genes, including several SLC genes, to promote glycolysis. SLC16A1 was upregulated after corpse uptake, increasing the release of lactate, a natural by-product of aerobic glycolysis3. Whereas glycolysis within phagocytes contributed to actin polymerization and the continued uptake of corpses, lactate released via SLC16A1 promoted the establishment of an anti-inflammatory tissue environment. Collectively, these data reveal a SLC program that is activated during efferocytosis, identify a previously unknown reliance on aerobic glycolysis during apoptotic cell uptake and show that glycolytic by-products of efferocytosis can influence surrounding cells.


Assuntos
Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Glucose/metabolismo , Ácido Láctico/metabolismo , Fagócitos/metabolismo , Fagocitose/genética , Transcriptoma/genética , Aerobiose , Animais , Apoptose , Linhagem Celular , Glicólise , Humanos , Inflamação/genética , Inflamação/prevenção & controle , Células Jurkat , Fagócitos/citologia , Análise de Sequência de RNA , Transcrição Genética , Peixe-Zebra
9.
Nature ; 564(7734): E7, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30397347

RESUMO

Change history: In this Article, Extended Data Fig. 9 was appearing as Fig. 2 in the HTML, and in Fig. 2, the panel labels 'n' and 'o' overlapped the figure; these errors have been corrected online.

10.
Nat Genet ; 50(10): 1366-1374, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30224649

RESUMO

To define potentially causal variants for autoimmune disease, we fine-mapped1,2 76 rheumatoid arthritis (11,475 cases, 15,870 controls)3 and type 1 diabetes loci (9,334 cases, 11,111 controls)4. After sequencing 799 1-kilobase regulatory (H3K4me3) regions within these loci in 568 individuals, we observed accurate imputation for 89% of common variants. We defined credible sets of ≤5 causal variants at 5 rheumatoid arthritis and 10 type 1 diabetes loci. We identified potentially causal missense variants at DNASE1L3, PTPN22, SH2B3, and TYK2, and noncoding variants at MEG3, CD28-CTLA4, and IL2RA. We also identified potential candidate causal variants at SIRPG and TNFAIP3. Using functional assays, we confirmed allele-specific protein binding and differential enhancer activity for three variants: the CD28-CTLA4 rs117701653 SNP, MEG3 rs34552516 indel, and TNFAIP3 rs35926684 indel.


Assuntos
Artrite Reumatoide/genética , Diabetes Mellitus Tipo 1/genética , Polimorfismo de Nucleotídeo Único , Alelos , Artrite Reumatoide/epidemiologia , Antígenos CD28/genética , Antígeno CTLA-4/genética , Estudos de Casos e Controles , Mapeamento Cromossômico , Diabetes Mellitus Tipo 1/epidemiologia , Frequência do Gene , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Humanos , Células Jurkat , Mutação , Locos de Características Quantitativas , RNA Longo não Codificante/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética
11.
Nature ; 560(7717): 185-191, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30046111

RESUMO

Ageing is a major risk factor for many neurological pathologies, but its mechanisms remain unclear. Unlike other tissues, the parenchyma of the central nervous system (CNS) lacks lymphatic vasculature and waste products are removed partly through a paravascular route. (Re)discovery and characterization of meningeal lymphatic vessels has prompted an assessment of their role in waste clearance from the CNS. Here we show that meningeal lymphatic vessels drain macromolecules from the CNS (cerebrospinal and interstitial fluids) into the cervical lymph nodes in mice. Impairment of meningeal lymphatic function slows paravascular influx of macromolecules into the brain and efflux of macromolecules from the interstitial fluid, and induces cognitive impairment in mice. Treatment of aged mice with vascular endothelial growth factor C enhances meningeal lymphatic drainage of macromolecules from the cerebrospinal fluid, improving brain perfusion and learning and memory performance. Disruption of meningeal lymphatic vessels in transgenic mouse models of Alzheimer's disease promotes amyloid-ß deposition in the meninges, which resembles human meningeal pathology, and aggravates parenchymal amyloid-ß accumulation. Meningeal lymphatic dysfunction may be an aggravating factor in Alzheimer's disease pathology and in age-associated cognitive decline. Thus, augmentation of meningeal lymphatic function might be a promising therapeutic target for preventing or delaying age-associated neurological diseases.


Assuntos
Envelhecimento/líquido cefalorraquidiano , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/fisiopatologia , Vasos Linfáticos/fisiopatologia , Meninges/fisiopatologia , Envelhecimento/patologia , Doença de Alzheimer/patologia , Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/metabolismo , Cognição , Transtornos Cognitivos/fisiopatologia , Transtornos Cognitivos/terapia , Modelos Animais de Doenças , Líquido Extracelular/metabolismo , Feminino , Homeostase , Humanos , Linfonodos/metabolismo , Vasos Linfáticos/patologia , Masculino , Meninges/patologia , Camundongos , Camundongos Transgênicos , Perfusão
12.
J Autoimmun ; 89: 90-100, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29310926

RESUMO

Traditional linkage analysis and genome-wide association studies have identified HLA and a number of non-HLA genes as genetic factors for islet autoimmunity (IA) and type 1 diabetes (T1D). However, the relative risk associated with previously identified non-HLA genes is usually very small as measured in cases/controls from mixed populations. Genetic associations for IA and T1D may be more accurately assessed in prospective cohorts. In this study, 5806 subjects from the TEDDY (The Environmental Determinants of Diabetes in the Young) study, an international prospective cohort study, were genotyped for 176,586 SNPs on the ImmunoChip. Cox proportional hazards analyses were performed to discover the SNPs associated with the risk for IA, T1D, or both. Three regions were associated with the risk of developing any persistent confirmed islet autoantibody: one known region near SH2B3 (HR = 1.35, p = 3.58 × 10-7) with Bonferroni-corrected significance and another known region near PTPN22 (HR = 1.46, p = 2.17 × 10-6) and one novel region near PPIL2 (HR = 2.47, p = 9.64 × 10-7) with suggestive evidence (p < 10-5). Two known regions (PTPN22: p = 2.25 × 10-6, INS; p = 1.32 × 10-7) and one novel region (PXK/PDHB: p = 8.99 × 10-6) were associated with the risk for multiple islet autoantibodies. First appearing islet autoantibodies differ with respect to association. Two regions (INS: p = 5.67 × 10-6 and TTC34/PRDM16: 6.45 × 10-6) were associated if the fist appearing autoantibody was IAA and one region (RBFOX1: p = 8.02 × 10-6) was associated if the first appearing autoantibody was GADA. The analysis of T1D identified one region already known to be associated with T1D (INS: p = 3.13 × 10-7) and three novel regions (RNASET2, PLEKHA1, and PPIL2; 5.42 × 10-6 > p > 2.31 × 10-6). These results suggest that a number of low frequency variants influence the risk of developing IA and/or T1D and these variants can be identified by large prospective cohort studies using a survival analysis approach.


Assuntos
Diabetes Mellitus Tipo 1/genética , Genótipo , Ilhotas Pancreáticas/imunologia , Autoanticorpos/metabolismo , Autoimunidade/genética , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Lactente , Recém-Nascido , Masculino , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Risco
13.
Diabetes ; 67(1): 146-154, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29061729

RESUMO

We examined the association between plasma 25-hydroxyvitamin D [25(OH)D] concentration and islet autoimmunity (IA) and whether vitamin D gene polymorphisms modify the effect of 25(OH)D on IA risk. We followed 8,676 children at increased genetic risk of type 1 diabetes at six sites in the U.S. and Europe. We defined IA as positivity for at least one autoantibody (GADA, IAA, or IA-2A) on two or more visits. We conducted a risk set sampled nested case-control study of 376 IA case subjects and up to 3 control subjects per case subject. 25(OH)D concentration was measured on all samples prior to, and including, the first IA positive visit. Nine polymorphisms in VDR, CYP24A, CYP27B1, GC, and RXRA were analyzed as effect modifiers of 25(OH)D. Adjusting for HLA-DR-DQ and ancestry, higher childhood 25(OH)D was associated with lower IA risk (odds ratio = 0.93 for a 5 nmol/L difference; 95% CI 0.89, 0.97). Moreover, this association was modified by VDR rs7975232 (interaction P = 0.0072), where increased childhood 25(OH)D was associated with a decreasing IA risk based upon number of minor alleles: 0 (1.00; 0.93, 1.07), 1 (0.92; 0.89, 0.96), and 2 (0.86; 0.80, 0.92). Vitamin D and VDR may have a combined role in IA development in children at increased genetic risk for type 1 diabetes.


Assuntos
Autoimunidade/fisiologia , Vitamina D/análogos & derivados , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/genética , Feminino , Predisposição Genética para Doença/genética , Humanos , Lactente , Recém-Nascido , Masculino , Polimorfismo de Nucleotídeo Único/genética , Vitamina D/sangue
14.
Sci Rep ; 7(1): 14623, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29116131

RESUMO

Phagocytes express multiple phosphatidylserine (PtdSer) receptors that recognize apoptotic cells. It is unknown whether these receptors are interchangeable or if they play unique roles during cell clearance. Loss of the PtdSer receptor Mertk is associated with apoptotic corpse accumulation in the testes and degeneration of photoreceptors in the eye. Both phenotypes are linked to impaired phagocytosis by specialized phagocytes: Sertoli cells and the retinal pigmented epithelium (RPE). Here, we overexpressed the PtdSer receptor BAI1 in mice lacking MerTK (Mertk -/- Bai1 Tg ) to evaluate PtdSer receptor compensation in vivo. While Bai1 overexpression rescues clearance of apoptotic germ cells in the testes of Mertk -/- mice it fails to enhance RPE phagocytosis or prevent photoreceptor degeneration. To determine why MerTK is critical to RPE function, we examined visual cycle intermediates and performed unbiased RNAseq analysis of RPE from Mertk +/+ and Mertk -/- mice. Prior to the onset of photoreceptor degeneration, Mertk -/- mice had less accumulation of retinyl esters and dysregulation of a striking array of genes, including genes related to phagocytosis, metabolism, and retinal disease in humans. Collectively, these experiments establish that not all phagocytic receptors are functionally equal, and that compensation among specific engulfment receptors is context and tissue dependent.


Assuntos
Apoptose , Células Germinativas/metabolismo , Fagocitose , Epitélio Pigmentado da Retina/metabolismo , Células de Sertoli/metabolismo , c-Mer Tirosina Quinase/metabolismo , Proteínas Angiogênicas/genética , Proteínas Angiogênicas/metabolismo , Animais , Células Germinativas/patologia , Humanos , Masculino , Camundongos , Camundongos Knockout , Epitélio Pigmentado da Retina/patologia , Células de Sertoli/patologia , c-Mer Tirosina Quinase/genética
15.
J Neurosci ; 37(48): 11744-11757, 2017 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-29066557

RESUMO

The retrotrapezoid nucleus (RTN) consists, by definition, of Phox2b-expressing, glutamatergic, non-catecholaminergic, noncholinergic neurons located in the parafacial region of the medulla oblongata. An unknown proportion of RTN neurons are central respiratory chemoreceptors and there is mounting evidence for biochemical diversity among these cells. Here, we used multiplexed in situ hybridization and single-cell RNA-Seq in male and female mice to provide a more comprehensive view of the phenotypic diversity of RTN neurons. We now demonstrate that the RTN of mice can be identified with a single and specific marker, Neuromedin B mRNA (Nmb). Most (∼75%) RTN neurons express low-to-moderate levels of Nmb and display chemoreceptor properties. Namely they are activated by hypercapnia, but not by hypoxia, and express proton sensors, TASK-2 and Gpr4. These Nmb-low RTN neurons also express varying levels of transcripts for Gal, Penk, and Adcyap1, and receptors for substance P, orexin, serotonin, and ATP. A subset of RTN neurons (∼20-25%), typically larger than average, express very high levels of Nmb mRNA. These Nmb-high RTN neurons do not express Fos after hypercapnia and have low-to-undetectable levels of Kcnk5 or Gpr4 transcripts; they also express Adcyap1, but are essentially devoid of Penk and Gal transcripts. In male rats, Nmb is also a marker of the RTN but, unlike in mice, this gene is expressed by other types of nearby neurons located within the ventromedial medulla. In sum, Nmb is a selective marker of the RTN in rodents; Nmb-low neurons, the vast majority, are central respiratory chemoreceptors, whereas Nmb-high neurons likely have other functions.SIGNIFICANCE STATEMENT Central respiratory chemoreceptors regulate arterial PCO2 by adjusting lung ventilation. Such cells have recently been identified within the retrotrapezoid nucleus (RTN), a brainstem nucleus defined by genetic lineage and a cumbersome combination of markers. Using single-cell RNA-Seq and multiplexed in situ hybridization, we show here that a single marker, Neuromedin B mRNA (Nmb), identifies RTN neurons in rodents. We also suggest that >75% of these Nmb neurons are chemoreceptors because they are strongly activated by hypercapnia and express high levels of proton sensors (Kcnk5 and Gpr4). The other RTN neurons express very high levels of Nmb, but low levels of Kcnk5/Gpr4/pre-pro-galanin/pre-pro-enkephalin, and do not respond to hypercapnia. Their function is unknown.


Assuntos
Bulbo/metabolismo , Neurocinina B/análogos & derivados , Animais , Feminino , Expressão Gênica , Hipóxia/genética , Hipóxia/metabolismo , Masculino , Bulbo/química , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurocinina B/análise , Neurocinina B/biossíntese , Neurocinina B/genética , Neurônios/química , Neurônios/metabolismo , Técnicas de Cultura de Órgãos , Ratos , Ratos Sprague-Dawley
16.
Genome Res ; 27(11): 1807-1815, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29025893

RESUMO

Genome-wide association studies (GWAS) have identified multiple, shared allelic associations with many autoimmune diseases. However, the pathogenic contributions of variants residing in risk loci remain unresolved. The location of the majority of shared disease-associated variants in noncoding regions suggests they contribute to risk of autoimmunity through effects on gene expression in the immune system. In the current study, we test this hypothesis by applying RNA sequencing to CD4+, CD8+, and CD19+ lymphocyte populations isolated from 81 subjects with type 1 diabetes (T1D). We characterize and compare the expression patterns across these cell types for three gene sets: all genes, the set of genes implicated in autoimmune disease risk by GWAS, and the subset of these genes specifically implicated in T1D. We performed RNA sequencing and aligned the reads to both the human reference genome and a catalog of all possible splicing events developed from the genome, thereby providing a comprehensive evaluation of the roles of gene expression and alternative splicing (AS) in autoimmunity. Autoimmune candidate genes displayed greater expression specificity in the three lymphocyte populations relative to other genes, with significantly increased levels of splicing events, particularly those predicted to have substantial effects on protein isoform structure and function (e.g., intron retention, exon skipping). The majority of single-nucleotide polymorphisms within T1D-associated loci were also associated with one or more cis-expression quantitative trait loci (cis-eQTLs) and/or splicing eQTLs. Our findings highlight a substantial, and previously underrecognized, role for AS in the pathogenesis of autoimmune disorders and particularly for T1D.


Assuntos
Processamento Alternativo , Diabetes Mellitus Tipo 1/genética , Perfilação da Expressão Gênica/métodos , Linfócitos/química , Análise de Sequência de RNA/métodos , Adulto , Linfócitos T CD4-Positivos/química , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/química , Linfócitos T CD8-Positivos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Feminino , Redes Reguladoras de Genes , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Linfócitos/imunologia , Masculino , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Locos de Características Quantitativas , Receptores CCR1/metabolismo
17.
J Clin Endocrinol Metab ; 102(8): 2873-2880, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28520980

RESUMO

Context: Genome-wide association studies identified >50 type 1 diabetes (T1D) associated non-human leukocyte antigens (non-HLA) loci. Objective: The purpose of this study was to assess the contribution of non-HLA single nucleotide polymorphisms (SNPs) to risk of disease progression. Design and Setting: The TrialNet Pathway to Prevention Study follows relatives of T1D patients for development of autoantibodies (Abs) and T1D. Participants: Using the Immunochip, we analyzed 53 diabetes-associated, non-HLA SNPs in 1016 Ab-positive, at-risk non-Hispanic white relatives. Main Outcome Measure: Effect of SNPs on the development of multiple Abs and T1D. Results: Cox proportional analyses included all substantial non-HLA SNPs, HLA genotypes, relationship to proband, sex, age at initial screening, initial Ab type, and number. Factors involved in progression from single to multiple Abs included age at screening, relationship to proband, HLA genotypes, and rs3087243 (cytotoxic T lymphocyte antigen-4). Significant factors for diabetes progression included age at screening, Ab number, HLA genotypes, rs6476839 [GLIS family zinc finger 3 (GLIS3)], and rs3184504 [SH2B adaptor protein 3 (SH2B3)]. When glucose area under the curve (AUC) was included, factors involved in disease progression included glucose AUC, age at screening, Ab number, relationship to proband, HLA genotypes, rs6476839 (GLIS3), and rs7221109 (CCR7). In stratified analyses by age, glucose AUC, age at screening, sibling, HLA genotypes, rs6476839 (GLIS3), and rs4900384 (C14orf64) were significantly associated with progression to diabetes in participants <12 years old, whereas glucose AUC, sibling, rs3184504 (SH2B3), and rs4900384 (C14orf64) were significant in those ≥12. Conclusions: In conclusion, we identified five non-HLA SNPs associated with increased risk of progression from Ab positivity to disease that may improve risk stratification for prevention trials.


Assuntos
Autoanticorpos/imunologia , Diabetes Mellitus Tipo 1/genética , Família , Adolescente , Adulto , Fatores Etários , Área Sob a Curva , Glicemia/metabolismo , Antígeno CTLA-4/genética , Proteínas de Transporte de Cátions/imunologia , Criança , Diabetes Mellitus Tipo 1/imunologia , Progressão da Doença , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Predisposição Genética para Doença , Genótipo , Teste de Tolerância a Glucose , Glutamato Descarboxilase/imunologia , Cadeias alfa de HLA-DQ/genética , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Humanos , Insulina/imunologia , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Polimorfismo de Nucleotídeo Único , Proteínas/genética , RNA Longo não Codificante/genética , Proteínas Tirosina Fosfatases Classe 8 Semelhantes a Receptores/imunologia , Receptores CCR7/genética , Risco , Medição de Risco , Fatores de Transcrição/genética , Adulto Jovem , Transportador 8 de Zinco
18.
Respir Res ; 18(1): 97, 2017 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-28521775

RESUMO

BACKGROUND: We conducted a genome-wide association study (GWAS) of subclinical interstitial lung disease (ILD), defined as high attenuation areas (HAA) on CT, in the population-based Multi-Ethnic Study of Atherosclerosis Study. METHODS: We measured the percentage of high attenuation areas (HAA) in the lung fields on cardiac CT scan defined as voxels with CT attenuation values between -600 and -250 HU. Genetic analyses were performed in MESA combined across race/ethnic groups: non-Hispanic White (n = 2,434), African American (n = 2,470), Hispanic (n = 2,065) and Chinese (n = 702), as well as stratified by race/ethnicity. RESULTS: Among 7,671 participants, regions at genome-wide significance were identified for basilar peel-core ratio of HAA in FLJ35282 downstream of ANRIL (rs7852363, P = 2.1x10-9) and within introns of SNAI3-AS1 (rs140142658, P = 9.6x10-9) and D21S2088E (rs3079677, P = 2.3x10-8). Within race/ethnic groups, 18 additional loci were identified at genome-wide significance, including genes related to development (FOXP4), cell adhesion (ALCAM) and glycosylation (GNPDA2, GYPC, GFPT1 and FUT10). Among these loci, SNP rs6844387 near GNPDA2 demonstrated nominal evidence of replication in analysis of n = 1,959 participants from the Framingham Heart Study (P = 0.029). FOXP4 region SNP rs2894439 demonstrated evidence of validation in analysis of n = 228 White ILD cases from the Columbia ILD Study compared to race/ethnicity-matched controls from MESA (one-sided P = 0.007). In lung tissue from 15 adults with idiopathic pulmonary fibrosis compared to 15 adults without lung disease. ANRIL (P = 0.001), ALCAM (P = 0.03) and FOXP4 (P = 0.046) were differentially expressed. CONCLUSIONS: Our results suggest novel roles for protein glycosylation and cell cycle disinhibition by long non-coding RNA in the pathogenesis of ILD.


Assuntos
Afro-Americanos/genética , Grupo com Ancestrais do Continente Asiático/genética , Grupo com Ancestrais do Continente Europeu/genética , Estudo de Associação Genômica Ampla/métodos , Hispano-Americanos/genética , Doenças Pulmonares Intersticiais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estudos Longitudinais , Doenças Pulmonares Intersticiais/diagnóstico , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Vigilância da População/métodos
19.
Ann Am Thorac Soc ; 14(5): 628-635, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28248552

RESUMO

RATIONALE: The receptor for advanced glycation end products (RAGE) is underexpressed in idiopathic pulmonary fibrosis (IPF) lung, but the role of RAGE in human lung fibrosis remains uncertain. OBJECTIVES: To examine (1) the association between IPF risk and variation at rs2070600, a functional missense variant in AGER (the gene that codes for RAGE), and (2) the associations between plasma-soluble RAGE (sRAGE) levels with disease severity and time to death or lung transplant in IPF. METHODS: We genotyped the rs2070600 single-nucleotide polymorphism in 108 adults with IPF and 324 race-/ethnicity-matched control subjects. We measured plasma sRAGE by ELISA in 103 adults with IPF. We used generalized linear and additive models as well as Cox models to control for potential confounders. We repeated our analyses in 168 (genetic analyses) and 177 (sRAGE analyses) adults with other forms of interstitial lung disease (ILD). RESULTS: There was no association between rs2070600 variation among adults with IPF (P = 0.31). Plasma sRAGE levels were lower among adults with IPF and other forms of ILD than in control subjects (P < 0.001). The rs2070600 allele A was associated with a 49% lower sRAGE level (95% confidence interval [CI], 11 to 71%; P = 0.02) among adults with IPF. In adjusted analyses, lower sRAGE levels were associated with greater disease severity (14% sRAGE decrement per 10% FVC decrement; 95% CI, 5 to 22%) and a higher rate of death or lung transplant at 1 year (adjusted hazard ratio, 1.9 per logarithmic unit of sRAGE decrement; 95% CI, 1.2-3.3) in IPF. Similar findings were observed in a heterogeneous group of adults with other forms of ILD. CONCLUSIONS: Lower plasma sRAGE levels may be a biological measure of disease severity in IPF. Variation at the rs2070600 single-nucleotide polymorphism was not associated with IPF risk.


Assuntos
Fibrose Pulmonar Idiopática/sangue , Fibrose Pulmonar Idiopática/genética , Receptor para Produtos Finais de Glicação Avançada/sangue , Receptor para Produtos Finais de Glicação Avançada/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Progressão da Doença , Feminino , Genótipo , Humanos , Fibrose Pulmonar Idiopática/cirurgia , Transplante de Pulmão , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Modelos de Riscos Proporcionais , Estudos Prospectivos , Solubilidade , Estados Unidos
20.
Sci Rep ; 7: 43859, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28266612

RESUMO

Depressive disorders often run in families, which, in addition to the genetic component, may point to the microbiome as a causative agent. Here, we employed a combination of behavioral, molecular and computational techniques to test the role of the microbiota in mediating despair behavior. In chronically stressed mice displaying despair behavior, we found that the microbiota composition and the metabolic signature dramatically change. Specifically, we observed reduced Lactobacillus and increased circulating kynurenine levels as the most prominent changes in stressed mice. Restoring intestinal Lactobacillus levels was sufficient to improve the metabolic alterations and behavioral abnormalities. Mechanistically, we identified that Lactobacillus-derived reactive oxygen species may suppress host kynurenine metabolism, by inhibiting the expression of the metabolizing enzyme, IDO1, in the intestine. Moreover, maintaining elevated kynurenine levels during Lactobacillus supplementation diminished the treatment benefits. Collectively, our data provide a mechanistic scenario for how a microbiota player (Lactobacillus) may contribute to regulating metabolism and resilience during stress.


Assuntos
Transtorno Depressivo/fisiopatologia , Microbioma Gastrointestinal/fisiologia , Mucosa Intestinal/metabolismo , Estresse Psicológico/fisiopatologia , Animais , Transtorno Depressivo/psicologia , Microbioma Gastrointestinal/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Intestinos/microbiologia , Cinurenina/sangue , Cinurenina/metabolismo , Lactobacillus/classificação , Lactobacillus/genética , Lactobacillus/fisiologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Dinâmica Populacional , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Estresse Psicológico/psicologia
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