Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Xenotransplantation ; 26(5): e12533, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31111577

RESUMEN

BACKGROUND: Anti-CD154 monoclonal antibody (mAb) treatment has been known to have potential to induce immune tolerance in organ transplantation. Several studies have suggested the involvement of CD4+ regulatory T cells (Treg s) in xeno-immune tolerance. However, the characteristics of Treg s and the mechanisms of their regulatory functions in islet xenotransplantation have not been clearly defined. METHOD: Adult porcine islet cells were isolated and purified, and were transplanted under the kidney capsule of diabetic C57BL/6J mice with the administration of 0.5 mg/mouse of anti-CD154 mAb on 0, 1, 3, 5, and 7 days post-transplantation (DPT). The graft survival was monitored by blood glucose level. The islet graft and recipients' cells were analyzed by immunohistochemistry (IHC), flow cytometry, enzyme-linked immunosorbent spot (ELISPOT) assay, and mixed-lymphocyte reaction. RESULTS: Short-term anti-CD154 mAb monotherapy enabled the porcine islet graft to survive indefinitely in diabetic mice (n = 18). Immunohistochemical staining showed significantly higher ratio of CD4+ Foxp3+ Treg s in the peri-graft site, but not in the spleen and kidney-draining lymph node of the recipient mice. Depletion of Treg s evoked graft rejection, and adoptive transfer of Treg s from anti-CD154 mAb-treated recipients provided protection to the graft from rejection. These Treg s showed more potent suppressive capacity than those from the untreated control and were found to be porcine antigen-specific. CONCLUSIONS: In this study, we showed that anti-CD154 mAb monotherapy resulted in indefinite porcine islet graft survival in mice. The porcine-specific CD4+ Foxp3+ Treg s in the peri-graft site played the critical role in the protection of islet graft from rejection, which suggests a prospective immunosuppressive strategy for islet xenotransplantation.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Linfocitos T CD4-Positivos/inmunología , Ligando de CD40/inmunología , Factores de Transcripción Forkhead/inmunología , Rechazo de Injerto/prevención & control , Trasplante de Islotes Pancreáticos , Trasplante Heterólogo , Animales , Anticuerpos Monoclonales/inmunología , Biomarcadores/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Diabetes Mellitus Experimental/cirugía , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Factores de Transcripción Forkhead/metabolismo , Rechazo de Injerto/diagnóstico , Rechazo de Injerto/inmunología , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Porcinos , Resultado del Tratamiento
2.
Xenotransplantation ; 23(4): 310-9, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27464486

RESUMEN

BACKGROUND: Recent progress in xenotransplantation of porcine islets to non-human primates (NHPs) gives hope for human clinical trials in the near future. Thus, implementation of an appropriate monitoring method to detect the development of detrimental porcine antigen-specific cellular immune responses is necessary. The enzyme-linked immunospot (ELISpot) assay has been widely used to monitor antigen-specific alloreactive T-cell responses in humans; however, the utility of porcine islet-specific ELISpot assay has not yet been thoroughly evaluated for pig-to-NHPs intraportal islet xenotransplantation. METHODS: The optimal ELISpot assay conditions, including the number of responder and stimulator cells and the provision of costimulation, were determined. Then, ELISpot assays were conducted on serial stocks of peripheral blood mononuclear cell (PBMC) samples previously isolated from NHP recipients transplanted with porcine islets. Either splenocytes from donor pigs or pancreatic islets from third-party pigs were used for antigen stimulation. At the same time, the ratio of CD4(+) /CD8(+) T cells and the percentage of CD4(+) FoxP3(+) T cells in the peripheral blood were evaluated. Finally, liver biopsy samples were evaluated to assess the immunopathology of the grafts. RESULTS: The optimal conditions for the ELISpot assay were defined as 2.5 × 10(5) responder cells incubated with 5.0 × 10(5) stimulator cells in 96-well, flat-bottom plates without further costimulation. Using donor splenocytes as stimulators, a serial interferon-gamma (IFN-γ) ELISpot assay with PBMCs from the monkeys with prolonged porcine islet grafts (>180 days) demonstrated that the number of donor antigen-specific IFN-γ-producing cells significantly increased upon overt graft rejection. However, use of third-party porcine islets as stimulators did not reflect graft rejection, suggesting that the use of donor-specific PBMCs, and not tissue (porcine islet)-specific cells, as stimulators could better serve the purpose of this assay in adult porcine islet transplantation. IFN-γ spot number was neither influenced by the peripheral blood CD4(+) /CD8(+) T-cell ratio nor the percentage of CD4(+) FoxP3(+) T cells. Finally, in cases of overt graft rejection, the number of IFN-γ spots and the graft-infiltrating T cells in biopsied liver samples increased simultaneously. CONCLUSION: Use of PBMCs in a porcine antigen-specific IFN-γ ELISpot assay is a reliable method for monitoring T-cell-mediated rejection in pig-to-NHP islet xenotransplantation.


Asunto(s)
Rechazo de Injerto/inmunología , Inmunidad Celular/inmunología , Interferón gamma/inmunología , Trasplante Heterólogo , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Xenoinjertos/inmunología , Islotes Pancreáticos/citología , Trasplante de Islotes Pancreáticos/métodos , Macaca mulatta , Porcinos , Trasplante Heterólogo/métodos
3.
Biochem Biophys Res Commun ; 441(2): 438-46, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24369900

RESUMEN

Human lymphoblastoid cell line (LCL) has been used as an in vitro cell model in genetic and pharmacogenomic studies, as well as a good model for studying gene expression regulatory machinery using integrated genomic analyses. In this study, we aimed to identify biological networks of LCL immortalization from transcriptomic profiles of microRNAs and their target genes in LCLs. We first selected differentially expressed genes (DEGs) and microRNAs (DEmiRs) between early passage LCLs (eLCLs) and terminally differentiated late passage LCLs (tLCLs). The in silico and correlation analysis of these DEGs and DEmiRs revealed that 1098 DEG-DEmiR pairs were found to be positively (n=591 pairs) or negatively (n=507 pairs) correlated with each other. More than 41% of DEGs are possibly regulated by miRNAs in LCL immortalizations. The target DEGs of DEmiRs were enriched for cellular functions associated with apoptosis, immune response, cell death, JAK-STAT cascade and lymphocyte activation while non-miRNA target DEGs were over-represented for basic cell metabolisms. The target DEGs correlated negatively with miR-548a-3p and miR-219-5p were significantly associated with protein kinase cascade, and the lymphocyte proliferation and apoptosis, respectively. In addition, the miR-106a and miR-424 clusters located in the X chromosome were enriched in DEmiR-mRNA pairs for LCL immortalization. In this study, the integrated transcriptomic analysis of LCLs could identify functional networks of biologically active microRNAs and their target genes involved in LCL immortalization.


Asunto(s)
Línea Celular Transformada , Regulación Leucémica de la Expresión Génica , Redes Reguladoras de Genes , MicroARNs/metabolismo , Cromosomas Humanos X/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Humanos , MicroARNs/genética , ARN Mensajero/genética , Transcriptoma
4.
J Hum Genet ; 58(1): 16-20, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23171997

RESUMEN

Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines (LCLs) promise to address the challenge posed by the limited availability of primary cells needed as a source of genomic DNA for genetic studies. However, the genetic stability of LCLs following prolonged culture has never been rigorously investigated. To evaluate genotypic errors caused by EBV integration into human chromosomes, we isolated genomic DNA from human peripheral blood mononuclear cells and LCLs collected from 20 individuals and genotyped the DNA samples using the Affymetrix 500K SNP array set. Genotype concordance measurements between two sources of DNA from the same individual indicated that genotypic discordance is negligible in early-passage LCLs (<20 passages) but substantial in late-passage LCLs (>50 passages). Analysis of concordance on a chromosome-by-chromosome basis identified genomic regions with a high frequency of genotypic errors resulting from the loss of heterozygosity observed in late-passage LCLs. Our findings suggest that, although LCLs harvested during early stages of propagation are a reliable source of genomic DNA for genetic studies, investigations that involve genotyping of the entire genome should not use DNA from late-passage LCLs.


Asunto(s)
Transformación Celular Viral/genética , Variación Genética , Leucocitos Mononucleares/virología , Adulto , Anciano , Línea Celular Transformada , Células Cultivadas , Genotipo , Herpesvirus Humano 4/fisiología , Humanos , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Integración Viral
5.
J Hum Genet ; 58(3): 120-6, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23364394

RESUMEN

Although over 30 common genetic susceptibility loci have been identified to be independently associated with coronary artery disease (CAD) risk through genome-wide association studies (GWAS), genetic risk variants reported to date explain only a small fraction of heritability. To identify novel susceptibility variants for CAD and confirm those previously identified in European population, GWAS and a replication study were performed in the Koreans and Japanese. In the discovery stage, we genotyped 2123 cases and 3591 controls with 521 786 SNPs using the Affymetrix SNP Array 6.0 chips in Korean. In the replication, direct genotyping was performed using 3052 cases and 4976 controls from the KItaNagoya Genome study of Japan with 14 selected SNPs. To maximize the coverage of the genome, imputation was performed based on 1000 Genome JPT+CHB and 5.1 million SNPs were retained. CAD association was replicated for three GWAS-identified loci (1p13.3/SORT1 (rs599839), 9p21.3/CDKN2A/2B (rs4977574), and 11q22.3/ PDGFD (rs974819)) in Koreans. From GWAS and a replication, SNP rs3782889 showed a strong association (combined P=3.95 × 10(-14)), although the association of SNP rs3782889 doesn't remain statistically significant after adjusting for SNP rs11066015 (proxy SNP with BRAP (r(2)=1)). But new possible CAD-associated variant was observed for rs9508025 (FLT1), even though its statistical significance did marginally reach at the genome-wide a significance level (combined P=6.07 × 10(-7)). This study shows that three CAD susceptibility loci, which were previously identified in European can be directly replicated in Koreans and also provides additional evidences implicating suggestive loci as risk variants for CAD in East Asian.


Asunto(s)
Enfermedad de la Arteria Coronaria/genética , Estudio de Asociación del Genoma Completo/métodos , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Pueblo Asiatico/genética , Estudios de Casos y Controles , Femenino , Sitios Genéticos , Predisposición Genética a la Enfermedad , Genoma Humano , Técnicas de Genotipaje , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
6.
Physiol Genomics ; 44(24): 1179-87, 2012 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-23073386

RESUMEN

Glucose ingestion-induced hyperglycemia has been known to induce inflammation, which is related to the pathogenesis of diabetic complications. To examine acute gene expression responses to physiological oral glucose ingestion in human circulating leukocytes, we conducted a microarray study of human circulating leukocytes sampled before, 1 h after, and 2 h after glucose ingestion in community-based participants without previous histories of diabetes (n = 60). Ingestion of 75 g glucose successfully induced acute hyperglycemia (glucose concentration 91.6 ± 5.3 mg/dl for fasting and 180.7 ± 48.5 mg/dl for 1 h after glucose ingestion). Oral glucose ingestion significantly increased the expressions of 23 genes and decreased the expressions of 13 genes [false discovery rate (FDR) P value <0.05]. These genes are significantly involved in immunity by way of natural killer cell-mediated immunity, granulocyte-mediated immunity, and the cytokine-mediated signaling pathway (FDR P value <0.05). The present study demonstrated 36 genes that showed acute gene expression change in human leukocytes within 1 h after glucose ingestion, suggesting that leukocytes participate in the inflammatory process induced by acute hyperglycemia. We believe that these results will provide some basic insight into the role of leukocytes in hyperglycemia-induced inflammation and the pathogenesis of diabetic complications.


Asunto(s)
Conducta Alimentaria/efectos de los fármacos , Perfilación de la Expresión Génica , Glucosa/administración & dosificación , Glucosa/farmacología , Hiperglucemia/genética , Inflamación/genética , Leucocitos/metabolismo , Adulto , Anciano , Glucemia/metabolismo , Células Cultivadas , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Hiperglucemia/sangre , Inmunidad/efectos de los fármacos , Inmunidad/genética , Inflamación/sangre , Insulina/sangre , Leucocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Modelos Genéticos , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados
7.
Crit Rev Eukaryot Gene Expr ; 22(3): 189-96, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23140160

RESUMEN

Human lymphoblastoid cell lines (LCLs) are generated by EBV-mediated B-cell transformation to provide unlimited genomic resources for human genetics and immunological studies. The LCL is a good in vitro cell model for assessing population differences in the basal expression of genes and miRNAs as well as in cellular responses to various stimulators. Recently, the utility of LCLs was extended to pharmacogenomic studies to discover genetic factors underlying individual variations in response to chemicals and environmental stresses. Although LCLs represent generally lymphoid tissue-specific biological characteristics, genomic signatures of LCLs can distinguish patients with brain-related diseases and nonlymphoid tumors from normal controls. MicroRNA is known to be an epigenetic transcriptional regulator, and its expression is induced in abnormal conditions such as perturbagen-stimulated, virus-infected, or cancer cells. The epigenetic regulation of gene expression mediated by microRNA and DNA methylation is important for understanding the pathogenesis of cancers and complex diseases as well as discovering for therapeutic targets. For integrative genomic analyses, LCLs can be utilized to generate cellular phenotypes and various genomic data (e.g., SNP, CNV, transcriptome, methylome, etc.), which can be linked to clinical information of donors. Here, we discuss miRNA-mediated gene expression in LCLs and its application to disease genomics and global transcriptional regulatory machinery studies.


Asunto(s)
Linfocitos B/metabolismo , Linfocitos B/virología , Línea Celular Transformada , MicroARNs/genética , Linfocitos B/citología , Transformación Celular Viral , Bases de Datos Genéticas , Epigénesis Genética , Regulación de la Expresión Génica , Herpesvirus Humano 4/fisiología , Humanos , MicroARNs/metabolismo , Transcriptoma
8.
Biochem Biophys Res Commun ; 427(2): 392-7, 2012 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-22995316

RESUMEN

Isoliquiritigenin (ISL) has been known to induce cell cycle arrest and apoptosis of various cancer cells. However, genetic factors regulating ISL effects remain unclear. The aim of this study was to identify the molecular signatures involved in ISL-induced cell death of EBV-transformed lymphoblastoid cell lines (LCLs) using microarray analyses. For gene expression and microRNA (miRNA) microarray experiments, each of 12 LCL strains was independently treated with ISL or DMSO as a vehicle control for a day prior to total RNA extraction. ISL treatment inhibited cell proliferation of LCLs in a dose-dependent manner. Microarray analysis showed that ISL-treated LCLs represented gene expression changes in cell cycle and p53 signaling pathway, having a potential as regulators in LCL survival and sensitivity to ISL-induced cytotoxicity. In addition, 36 miRNAs including five miRNAs with unknown functions were differentially expressed in ISL-treated LCLs. The integrative analysis of miRNA and gene expression profiles revealed 12 putative mRNA-miRNA functional pairs. Among them, miR-1207-5p and miR-575 were negatively correlated with p53 pathway- and cell cycle-associated genes, respectively. In conclusion, our study suggests that miRNAs play an important role in ISL-induced cytotoxicity in LCLs by targeting signaling pathways including p53 pathway and cell cycle.


Asunto(s)
Antineoplásicos/farmacología , Chalconas/farmacología , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Trastornos Linfoproliferativos/metabolismo , MicroARNs/biosíntesis , Línea Celular Tumoral , Expresión Génica/efectos de los fármacos , Humanos , Trastornos Linfoproliferativos/genética , Análisis de Secuencia por Matrices de Oligonucleótidos
9.
J Immunol ; 185(7): 4022-9, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20802154

RESUMEN

Disease amelioration by mesenchymal stem cells (MSCs) has been shown to be closely related to their immunomodulatory functions on the host immune system in many disease models. However, the underlying mechanisms of how these cells affect the immune cells in vivo are not fully understood. In this study, we report findings that a small but significant number of MSCs accumulate in the secondary lymphoid organs and attenuate delayed-type hypersensitivity (DTH) response by inducing apoptotic cell death of surrounding immune cells in the draining lymph node (LN). In the migration study, i.v. infused GFP-MSCs preferentially accumulated at the boundary between the paracortical area and the germinal center in the LNs, in close proximity to various types of immune cells including T, B, and dendritic cells in a dose-dependent manner. As a result, accumulated MSCs markedly attenuated DTH response in proportion to the number of MSCs infused. During the DTH response, the infiltration of T cells in the challenged site was significantly decreased, whereas a number of apoptotic T cells were remarkably increased in the draining LN. Apoptosis was significantly induced in activated T cells (CD3(+) and BrdU(+)), but not in the resting T cells (CD3(+) and BrdU(-)). NO was associated with these apoptotic events. Taken together, we conclude that significant numbers of i.v. infused MSCs preferentially localize in the draining LN, where they induce apoptosis of the activated T cells by producing NO and thus attenuate the DTH response.


Asunto(s)
Apoptosis/inmunología , Quimiotaxis de Leucocito/inmunología , Hipersensibilidad Tardía/inmunología , Inmunomodulación/inmunología , Células Madre Mesenquimatosas/inmunología , Linfocitos T/inmunología , Animales , Efecto Espectador/inmunología , Separación Celular , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Hipersensibilidad Tardía/metabolismo , Etiquetado Corte-Fin in Situ , Ganglios Linfáticos/citología , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/patología , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Óxido Nítrico/inmunología , Óxido Nítrico/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T/patología
10.
BMC Genomics ; 11: 426, 2010 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-20624279

RESUMEN

BACKGROUND: Recent efforts have been made to link complex human traits and disease susceptibility to DNA copy numbers. The leptin receptor (LEPR) has been implicated in obesity and diabetes. Mutations and genetic variations of LEPR gene have been discovered in rodents and humans. However, the association of DNA copy number variations at the LEPR gene locus with human complex diseases has not been reported. In an attempt to study DNA copy number variations associated with metabolic traits and type 2 diabetes mellitus (T2DM), we targeted the LEPR gene locus in DNA copy number analyses. RESULTS: We identified DNA copy number variations at the LEPR gene locus among a Korean population using genome-wide SNP chip data, and then quantified copy numbers of the E2 DNA sequence in the first two exons overlapped between LEPR and LEPROT genes by the quantitative multiplex PCR of short fluorescent fragment (QMPSF) method. Among the non-diabetic subjects (n = 1,067), lower E2 DNA copy numbers were associated with higher fasting glucose levels in men (p = 1.24 x 10(-7)) and women (p = 9.45 x 10(-5)), as well as higher total cholesterol levels in men (p = 9.96 x 10(-7)). In addition, the significant association between lower E2 DNA copy numbers and lower level of postprandial 2 hr insulin was evident only in non-diabetic women, whereas some obesity-related phenotypes and total cholesterol level exhibited significant associations only in non-diabetic men. Logistic regression analysis indicated that lower E2 DNA copy numbers were associated with T2DM (odds ratio, 1.92; 95% CI, 1.26-2.96; p < 0.003) in our nested case-control study. Interestingly, the E2 DNA copy number exhibited a negative correlation with LEPR gene expression, but a positive correlation with LEPROT gene expression. CONCLUSIONS: This work suggests that a structural variation at the LEPR gene locus is functionally associated with complex metabolic traits and the risk of T2DM.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Dosificación de Gen , Receptores de Leptina/genética , Glucemia/genética , Colesterol/sangre , Femenino , Sitios Genéticos , Predisposición Genética a la Enfermedad , Humanos , Corea (Geográfico) , Masculino
11.
Exp Mol Med ; 41(5): 315-24, 2009 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-19307751

RESUMEN

Mesenchymal stem cells (MSCs) can inhibit T cell proliferation; however, the underlying mechanisms are not clear. In this study, we investigated the mechanisms of the immunoregulatory activity of MSCs on T cells. Irradiated MSCs co-cultured with either na?ve or pre-activated T cells in a mixed lymphocyte reaction (MLR) significantly suppressed T cell proliferation in a dose-dependent manner, irrespective of allogeneic disparity between responders and MSCs. Transwell assays revealed that the suppressive effect was primarily mediated by soluble factors that induced apoptosis. Splenocytes stimulated with alloantigen in the presence of the MSC culture supernatant (CS) produced a significant amount of IL-10, which was attributed to an increase in the number of IL-10 secreting cells, confirmed by an ELISPOT assay. The blockade of IL-10 and IL-10 receptor interaction by anti-IL-10 or anti-IL-10-receptor antibodies abrogated the suppressive capacity of MSC CS, indicating that IL-10 plays a major role in the suppression of T cell proliferation. The addition of 1-methyl-DL-tryptophan (1-MT), an indoleamine 2,3-dioxygenase (IDO) inhibitor, also restored the proliferative capacity of T cells. In conclusion, we demonstrated that soluble mediators from culture supernatant of MSCs could suppress the proliferation of both naive and pre-activated T cells in which IL-10 and IDO play important roles.


Asunto(s)
Interleucina-10/biosíntesis , Activación de Linfocitos , Células Madre Mesenquimatosas/metabolismo , Linfocitos T/inmunología , Animales , Proliferación Celular , Células Cultivadas , Indolamina-Pirrol 2,3,-Dioxigenasa/antagonistas & inhibidores , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Linfocinas/farmacología , Células Madre Mesenquimatosas/citología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Receptores de Interleucina-10/metabolismo , Linfocitos T/citología , Linfocitos T/metabolismo , Triptófano/análogos & derivados , Triptófano/farmacología
12.
Mol Cells ; 27(2): 143-8, 2009 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-19277495

RESUMEN

EBV-transformed lymphoblastoid cell lines (LCLs) are used as a resource for human genetic, immunological, and pharmacogenomic studies. We investigated the biological activity of 20 LCL strains during continuous long-term subculture up to a passage number of 160. Out of 20 LCL strains, 17 proliferated up to a passage number of 160, at which point LCLs are generally considered as "immortalized". The other three LCL strains lost the ability to proliferate at an average passage number of 41, during which these LCLs may have undergone cellular crisis. These non-immortal LCL strains exhibited no telomerase activity, decreased EBV gene expression, and a lower copy number of the EBV genome and mitochondrial DNA when compared with immortal LCLs. Thus, this study suggests that sustained EBV viral activity as well as telomerase activity may be required for complete LCL immortalization.


Asunto(s)
Linfocitos B/patología , Linfocitos B/virología , Transformación Celular Viral/fisiología , Herpesvirus Humano 4/fisiología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Telomerasa/metabolismo , Telómero/fisiología
13.
J Allergy Clin Immunol ; 122(6): 1119-1126.e7, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18962861

RESUMEN

BACKGROUND: CXCR3 is a chemokine receptor that plays important roles in mediating chemotactic signals and modulating the activation of lymphocytes. We have previously conducted a case-control study by using a candidate gene approach to investigate the association of CXCR3 polymorphisms with the risk of asthma. Results from the epidemiologic study showed that a common nucleotide variant in the CXCR3 intron (rs2280964G>A) was associated with disease susceptibility (1006 cases and 384 control subjects; odds ratio, 0.81; 95% CI, 0.69-0.94; P = .007). OBJECTIVE: The aim of our study was to evaluate the epidemiologic study and provide functional evidence for the association of rs2280964G>A with asthma by investigating the effects of intronic variant on chemokine-mediated phenotypes of human-derived T cells. METHODS: We used cell line-based in vitro and human primary T cell-based ex vivo studies to examine the functional consequences of the intronic polymorphism, focusing on the regulation of gene expression, splicing, and immune responsiveness toward activating signals. RESULTS: We present functional evidence indicating that the rs2280964A allele significantly correlates with decreased CXCR3 gene expression, which would lead to variation in immune cell responses to chemokine-cytokine signals in vitro and ex vivo that includes a decrease in chemotactic activity. CONCLUSION: These findings, in conjunction with those of our previous epidemiologic studies, might implicate a functional link between a common nucleotide variant of a chemokine receptor gene, CXCR3, and a cause for a complex-trait disease, asthma.


Asunto(s)
Asma/genética , Regulación de la Expresión Génica/genética , Predisposición Genética a la Enfermedad , Intrones/genética , Polimorfismo de Nucleótido Simple , Receptores CXCR3/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Asma/epidemiología , Asma/inmunología , Estudios de Casos y Controles , Línea Celular Transformada , Quimiocinas/inmunología , Quimiotaxis/genética , Quimiotaxis/inmunología , Niño , Preescolar , Femenino , Regulación de la Expresión Génica/inmunología , Humanos , Intrones/inmunología , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Masculino , Persona de Mediana Edad , Sitios de Carácter Cuantitativo/genética , Sitios de Carácter Cuantitativo/inmunología , Receptores CXCR3/inmunología , Transducción de Señal/genética , Transducción de Señal/inmunología , Linfocitos T/inmunología
14.
Mol Cancer Res ; 17(1): 84-96, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30131446

RESUMEN

The Cancer Genome Atlas (TCGA) and other large-scale genomic data pipelines have been integral to the current understanding of the molecular events underlying renal cell carcinoma (RCC). These data networks have focused mostly on primary RCC, which often demonstrates indolent behavior. However, metastatic disease is the major cause of mortality associated with RCC and data sets examining metastatic tumors are sparse. Therefore, a more comprehensive analysis of gene expression and DNA methylome profiling of metastatic RCC in addition to primary RCC and normal kidney was performed. Integrative analysis of the methylome and transcriptome identified over 30 RCC-specific genes whose mRNA expression inversely correlated with promoter methylation, including several known targets of hypoxia inducible factors. Notably, genes encoding several metabolism-related proteins were identified as differentially regulated via methylation including hexokinase 2, aldolase C, stearoyl-CoA desaturase, and estrogen-related receptor-γ (ESRRG), which has a known role in the regulation of nuclear-encoded mitochondrial metabolism genes. Several gene expression changes could portend prognosis in the TCGA cohort. Mechanistically, ESRRG loss occurs via DNA methylation and histone repressive silencing mediated by the polycomb repressor complex 2. Restoration of ESRRG in RCC lines suppresses migratory and invasive phenotypes independently of its canonical role in mitochondrial metabolism. IMPLICATIONS: Collectively, these data provide significant insight into the biology of aggressive RCC and demonstrate a novel role for DNA methylation in the promotion of HIF signaling and invasive phenotypes in renal cancer.


Asunto(s)
Epigenómica/métodos , Regulación Neoplásica de la Expresión Génica/genética , Neoplasias Renales/genética , Progresión de la Enfermedad , Humanos , Neoplasias Renales/patología , Metástasis de la Neoplasia
15.
Mol Cells ; 26(5): 459-61, 2008 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-18688176

RESUMEN

Much research evidence supports the hypothesis that chronic, low-grade inflammation related to innate immunity may play an important role in the pathophysiology of type 2 diabetes mellitus (T2DM). Runt-related transcription factor 2 (RUNX2; MIM# 600211) acts as a scaffold that controls the integration, organization, and assembly of nucleic acids. To examine whether the novel promoter variant in RUNX2 is associated with the risk of T2DM and related phenotypes, RUNX2-742G > T was genotyped in 378 T2DM patients and 382 normal controls recruited in the Korean T2DM Study. Statistical analysis revealed that RUNX2-742G > T was associated with serum triglyceride level (TG) in nondiabetic controls, although it was not associated with the risk of T2DM. Individuals who carry T/T, T/G, and G/G genotypes had the highest (2.061 +/- 0.20), intermediate (2.01 +/- 0.19), and the lowest (1.97 +/- 0.18) levels of log [TG (mmol/l)] (P = 0.007), respectively. Our data on this important variant of RUNX2 suggest that lipid metabolism might be affected by genetic polymorphisms in the promoter region.


Asunto(s)
Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas , Triglicéridos/sangre , Adulto , Anciano , Anciano de 80 o más Años , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Análisis de Regresión , Caracteres Sexuales
16.
Protein Pept Lett ; 15(9): 980-4, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18991775

RESUMEN

An efficient asymmetric synthesis of 6-aminobicyclo[2.2.1]heptane-2-carboxylic acid as a novel gamma-turn mimic has been achieved. Structural analysis of the gamma-amino acid derivative was carried out using (1)H NMR spectroscopy and intramolecular hydrogen bonding between side chain amides confirmed the turn structure, which had been predicted by Ab initio computational study.


Asunto(s)
Aminoácidos Cíclicos/química , Aminoácidos Cíclicos/síntesis química , Compuestos Bicíclicos con Puentes/química , Compuestos Bicíclicos con Puentes/síntesis química , Heptanos/química , Enlace de Hidrógeno , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Imitación Molecular , Estructura Molecular , Norbornanos , Estructura Secundaria de Proteína
17.
Cancer Genet Cytogenet ; 173(2): 122-30, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17321327

RESUMEN

Array CGH has been applied to detect chromosomal aberrations in cancer and genetic diseases. Epstein-Barr virus (EBV)-infected B lymphocytes are transformed to continuously proliferating lymphoblastoid cell lines (LCLs), which are a very common genome resource for human genetic studies. We used bacterial artificial chromosome (BAC) array CGH to assess a chromosomal aberration of LCLs in EBV-induced B-cell transformation. At early passages, LCLs exhibited a greater copy number variation in 1p36.33 compared to primary B-cells. Quantitative polymerase chain reaction (PCR) confirmed the increase in the copy number in 1p36.33. Because a segment of 1p36.33 is nearly identical to a part of the mitochondrial DNA, this increase was attributed to an increase in the copy number of mitochondrial DNA. The expression levels of mitochondrial biogenesis-related genes were elevated in the LCLs, which is consistent with the increased copy numbers of mitochondrial DNA, suggesting that increased mitochondrial biogenesis is indicative of the progression of EBV-mediated B-cell transformation. In addition, our array CGH of LCLs revealed potential copy number polymorphisms of chromosomal segments among Korean populations. Taken together, these findings suggest that LCLs in the early passages preserve the chromosomal integrity of primary B-cells at the cytogenetic level during EBV-transformed B-cell immortalization, except for a copy number variation in 1p36.33 due to increased mitochondrial DNA copy numbers. Thus, analyses of array CGH profiles of diseases should take into account the potential for copy number variation of 1p36.33.


Asunto(s)
Aneuploidia , Cromosomas Humanos Par 1/genética , ADN Mitocondrial/genética , Amplificación de Genes , Linfocitos/metabolismo , Línea Celular Transformada , Transformación Celular Viral/genética , Cromosomas Artificiales Bacterianos/genética , Expresión Génica , Genoma Humano/genética , Herpesvirus Humano 4/fisiología , Humanos , Linfocitos/patología , Linfocitos/virología , Análisis por Micromatrices/métodos , Proteínas Mitocondriales/genética , Hibridación de Ácido Nucleico/métodos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
18.
Sci Rep ; 7: 43203, 2017 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-28251996

RESUMEN

Here, we tested the performance of the mitochondrial DNA copy number (mtDNA-CN) in predicting future type 2 diabetes (n = 1108). We used the baseline clinical data (age, sex, body mass index, waist-to-hip ratio, systolic and diastolic blood pressure) and the mtDNA-CN, hemoglobin A1c (A1C) levels and results of oral glucose tolerance test (OGTT) including fasting plasma glucose, 1-hour glucose, and 2-hour glucose levels, to predict future diabetes. We built a prediction model using the baseline data and the diabetes status at biannual follow-up of 8 years. The mean area under curve (AUC) for all follow-ups of the full model including all variables was 0.92 ± 0.04 (mean ± standard deviation), while that of the model excluding the mtDNA-CN was 0.90 ± 0.03. The sensitivity of the f4ull model was much greater than that of the model not including mtDNA-CN: the mean sensitivities of the model with and without mtDNA-CN were 0.60 ± 0.06 and 0.53 ± 0.04, respectively. We found that the mtDNA-CN of peripheral leukocytes is a biomarker that augments the predictive power for future diabetes of A1C and OGTT. We believe that these results could provide invaluable information for developing strategies for the management of diabetes.


Asunto(s)
Variaciones en el Número de Copia de ADN , ADN Mitocondrial/genética , Técnicas de Apoyo para la Decisión , Diabetes Mellitus Tipo 2/diagnóstico , Prueba de Tolerancia a la Glucosa , Hemoglobina Glucada/análisis , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
19.
Colloids Surf B Biointerfaces ; 157: 215-222, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28599182

RESUMEN

We developed a calcium phosphate (CaP)-assembled polymer nanocarrier for intracellular doxorubicin (DOX) delivery based on a mussel-inspired mineralization approach. A DOX-loaded core-shell polymer nanoparticle (DOX-NP) consisting of a poly(3,4-dihydroxy-l-phenylalanine) (PDOPA) core and a poly (ethylene glycol) (PEG) shell was utilized as a nanotemplate for CaP mineralization. The mean hydrodynamic diameter of the DOX-loaded CaP-mineralized polymer nanoparticles (DOX-CaP-NPs) was 154.3nm. Energy-dispersive X-ray spectroscopy confirmed that the DOX-CaP-NPs contained substantial amounts of Ca and P, elements found only in the CaP mineral. The loading efficiency and content of DOX, estimated by fluorescence spectroscopy, were 54.0% and 10.8wt%, respectively. The CaP deposited in the PDOPA core domain enabled the DOX-CaP-NPs to maintain a robust structure and effectively inhibit DOX release at extracellular pH, whereas at endosomal pH, the CaP core dissolved to trigger a facilitated DOX release. The DOX-CaP-NPs may serve as robust nanocarriers with a high delivery efficacy for cancer chemotherapy.


Asunto(s)
Bivalvos , Fosfatos de Calcio/química , Portadores de Fármacos/química , Polietilenglicoles/química , Animales , Doxorrubicina/química , Nanopartículas/química , Espectrometría de Fluorescencia
20.
Cell Mol Immunol ; 12(5): 592-603, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26211666

RESUMEN

Regulatory T cells (Tregs) are a specialized subpopulation of T cells that control the immune response and thereby maintain immune system homeostasis and tolerance to self-antigens. Many subsets of CD4(+) Tregs have been identified, including Foxp3(+), Tr1, Th3, and Foxp3neg iT(R)35 cells. In this study, we identified a new subset of CD4(+)VEGFR1(high) Tregs that have immunosuppressive capacity. CD4(+)VEGFR1high T cells, which constitute approximately 1.0% of CD4(+) T cells, are hyporesponsive to T-cell antigen receptor stimulation. Surface marker and FoxP3 expression analysis revealed that CD4(+)VEGFR1(high) T cells are distinct from known Tregs. CD4(+)VEGFR1(high) T cells suppressed the proliferation of CD4(+)CD25(-) T cell as efficiently as CD4(+)CD25(high) natural Tregs in a contact-independent manner. Furthermore, adoptive transfer of CD4(+)VEGFR1(+) T cells from wild type to RAG-2-deficient C57BL/6 mice inhibited effector T-cell-mediated inflammatory bowel disease. Thus, we report CD4(+) VEGFR1(high) T cells as a novel subset of Tregs that regulate the inflammatory response in the intestinal tract.


Asunto(s)
Antígenos CD4/metabolismo , Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades Inflamatorias del Intestino/inmunología , Linfopenia/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T Reguladores/inmunología , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Traslado Adoptivo , Animales , Anticuerpos Monoclonales/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Factores de Transcripción Forkhead/metabolismo , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Linfopenia/complicaciones , Ratones Endogámicos C57BL , Ratones Noqueados , Pruebas de Neutralización , Fenotipo , Receptores de Antígenos de Linfocitos T/metabolismo , Solubilidad , Subgrupos de Linfocitos T/efectos de los fármacos , Linfocitos T Reguladores/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA