941 resultados para T(H)17 CELLS


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The gene transfer efficiency of human hematopoietic stem cells is still inadequate for efficient gene therapy of most disorders. To overcome this problem, a selectable retroviral vector system for gene therapy has been developed for gene therapy of Gaucher disease. We constructed a bicistronic retroviral vector containing the human glucocerebrosidase (GC) cDNA and the human small cell surface antigen CD24 (243 bp). Expression of both cDNAs was controlled by the long terminal repeat enhancer/promoter of the Molony murine leukemia virus. The CD24 selectable marker was placed downstream of the GC cDNA and its translation was enhanced by inclusion of the long 5' untranslated region of encephalomyocarditis virus internal ribosomal entry site. Virus-producing GP+envAM12 cells were created by multiple supernatant transductions to create vector producer cells. The vector LGEC has a high titer and can drive expression of GC and the cell surface antigen CD24 simultaneously in transduced NIH 3T3 cells and Gaucher skin fibroblasts. These transduced cells have been successfully separated from untransduced cells by fluorescence-activated cell sorting, based on cell surface expression of CD24. Transduced and sorted NIH 3T3 cells showed higher GC enzyme activity than the unsorted population, demonstrating coordinated expression of both genes. Fibroblasts from Gaucher patients were transduced and sorted for CD24 expression, and GC enzyme activity was measured. The transduced sorted Gaucher fibroblasts had a marked increase in enzyme activity (149%) compared with virgin Gaucher fibroblasts (17% of normal GC enzyme activity). Efficient transduction of CD34+ hematopoietic progenitors (20-40%) was accomplished and fluorescence-activated cell sorted CD24(+)-expressing progenitors generated colonies, all of which (100%) were vector positive. The sorted, CD24-expressing progenitors generated erythroid burst-forming units, colony-forming units (CFU)-granulocyte, CFU-macrophage, CFU-granulocyte/macrophage, and CFU-mix hematopoietic colonies, demonstrating their ability to differentiate into these myeloid lineages in vitro. The transduced, sorted progenitors raised the GC enzyme levels in their progeny cells manyfold compared with untransduced CD34+ progenitors. Collectively, this demonstrates the development of high titer, selectable bicistronic vectors that allow isolation of transduced hematopoietic progenitors and cells that have been metabolically corrected.

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The t(15;17) chromosomal translocation, specific for acute promyelocytic leukemia (APL), fuses the PML gene to the retinoic acid receptor alpha (RAR alpha) gene, resulting in expression of a PML-RAR alpha hybrid protein. In this report, we analyzed the nature of PML-RAR alpha-containing complexes in nuclear protein extracts of t(15;17)-positive cells. We show that endogenous PML-RAR alpha can bind to DNA as a homodimer, in contrast to RAR alpha that requires the retinoid X receptor (RXR) dimerization partner. In addition, these cells contain oligomeric complexes of PML-RAR alpha and endogenous RXR. Treatment with retinoic acid results in a decrease of PML-RAR alpha protein levels and, as a consequence, of DNA binding by the different complexes. Using responsive elements from various hormone signaling pathways, we show that PML-RAR alpha homodimers have altered DNA-binding characteristics when compared to RAR alpha-RXR alpha heterodimers. In transfected Drosophila SL-3 cells that are devoid of endogenous retinoid receptors PML-RAR alpha inhibits transactivation by RAR alpha-RXR alpha heterodimers in a dominant fashion. In addition, we show that both normal retinoid receptors and the PML-RAR alpha hybrid bind and activate the peroxisome proliferator-activated receptor responsive element from the Acyl-CoA oxidase gene, indicating that retinoids and peroxisome proliferator receptors may share common target genes. These properties of PML-RAR alpha may contribute to the transformed phenotype of APL cells.

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The lacZ transgenic mouse (Muta mouse) model was used to examine the timing of ethylnitrosourea (ENU)-induced mutations in germ cells. The spectrum of mutations was also determined. Animals received five daily treatments with ENU at 50 mg/kg and were sampled at times up to 55 days after treatment. In mixed germ-cell populations isolated from seminiferous tubules, there was little increase in the mutant frequency 5 days after treatment; subsequently, there was a continuous increase until the maximum (17.5-fold above background) was reached by approximately 35 days. In the spermatozoa, an increase in mutant frequency was not seen until 20 days after treatment, with the maximum (4.3-fold above background) being achieved no sooner than approximately 35 days. Based on the timing of sampling, these data demonstrate the detection of both spermatogonial and postspermatogonial, mutations. The most prominent feature of the ENU-induced base-pair mutations in testicular germ cells sampled 55 days after treatment is that 70% are induced in A.T base pairs, compared to only 16% in spontaneous mutations. These findings are consistent with comparable data from ENU studies using assays for inherited germ-cell mutations in mice. This study has demonstrated the utility and potential of the transgenic mouse lacZ model (Muta mouse) for the detection and study of germ-cell mutations and provides guidance in the selection of simplified treatment and sampling protocols.

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Erythroid progenitor growth in vitro is stimulated by exogenous platelet-derived growth factor (PDGF). We now report that both normal and transformed erythroid progenitor cells produce authentic PDGF in vitro and in vivo. Importantly, this production is highly regulated during erythropoiesis. Addition of soluble lysates from Rauscher murine erythroleukemia cells--an erythropoietin-responsive model progenitor cell line--to quiescent BALB/c 3T3 fibroblasts resulted in a mitogenic response identical to that observed with the addition of authentic recombinant PDGF. Polyclonal and monoclonal anti-PDGF antibodies immunoabsorbed 50-100% of this activity. Induction of Rauscher cell differentiation in vitro with dimethyl sulfoxide or erythropoietin for 48-72 hr markedly upregulated PDGF production by 17- to 18-fold and 14- to 38-fold, respectively. Importantly, stimulation of normal erythropoiesis in vivo in mice treated either with phenylhydrazine or with erythropoietin increased PDGF levels in the spleen by 11- to 48-fold and 20- to 34-fold, respectively. These results strongly suggest a role for erythroid cell-derived PDGF in normal erythropoiesis and provide documentation of the regulated production of a pleiotropic cytokine by erythroid cells.

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We have attempted to model human metastatic disease by implanting human target organs into the immunodeficient C.B-17 scid/scid (severe combined immunodeficiency; SCID) mouse, creating SCID-hu mice. Preferential metastasis to implants of human fetal lung and human fetal bone marrow occurred after i.v. injection of human small cell lung cancer (SCLC) cells into SCID-hu mice; the homologous mouse organs were spared. Clinically more aggressive variant SCLC cells metastasized more efficiently to human fetal lung implants than did cells from classic SCLC. Metastasis of variant SCLC to human fetal bone marrow was enhanced in SCID-hu mice exposed to gamma-irradiation or to interleukin 1 alpha. These data indicate that the SCID-hu mice may provide a model in which to study species- and tissue-specific steps of the human metastatic process.

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This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Acknowledgements The authors would like to thank Dr Marius Sudol for the hYAP plasmids (obtained through Addgene), Dr Pete Zammit for the pMSCV-IRES-eGFP plasmid, Dr Robert Judson for subcloning the hYAP cDNAs into the pMSCV-IRES-eGFP plasmid, Dr Lynda Erskine for the provision of mouse embryo samples, and Professor Jimmy Hutchison and the Orthopaedics Department at the Aberdeen Royal Infirmary for the provision of human tissue samples. The authors are also grateful to Denise Tosh and Susan Clark for excellent technical support. This work was funded by Arthritis Research UK (grant 19429).

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Les glucocorticoïdes sont les médicaments les plus efficaces pour le contrôle de l'obstruction respiratoire chez les chevaux atteints du souffle, et de l'asthme humain. Toutefois, les neutrophiles persistent dans les voies respiratoires suite à ce traitement. Nous avons précédemment rapporté que les neutrophiles sanguins humains et équins sont sensibles à l'action des glucocorticoïdes. Comme elle contribue à l'insensibilité des cellules épithéliales pulmonaires humaines aux glucocorticoïdes, nous avons émis l'hypothèse que l'IL-17 a un effet similaire sur les neutrophiles et qu’elle contribue à leur persistance dans les voies respiratoires asthmatiques. Objectifs : Évaluer 1. L’expression des deux sous-unités du récepteur de l’IL-17 (l'IL-17RA/IL-17RC) chez les neutrophiles équins hautement purifiés. 2. Si l'IL-17 active directement les neutrophiles et si cette réponse est sensible à l'action des glucocorticoïdes. 3. L'effet de l'IL-17 sur la viabilité et l'apoptose des neutrophiles. Résultats: 1. Les neutrophiles expriment l’IL-17RA/IL-17RC aux niveaux translationnel et protéique. 2. L’IL-17 induit une activation sélective des neutrophiles (surrégulation de l’IL-8), qui n’est pas atténuée par dexaméthasone et 3. l’IL-17 augmente la viabilité des neutrophiles stimulés (LPS) par une diminution de l'apoptose. Nos résultats indiquent que l'IL-17 active directement le neutrophile équin, et que l’augmentation de l’IL-8 (puissant chimioatractant des neutrophiles) qui en résulte n’est pas contrôlée par la dexaméthasone. L'IL-17 pourrait aussi contribuer à la persistance de neutrophiles dans les voies respiratoires chez les chevaux atteints du souffle, en diminuant l'apoptose.

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El lenguado de California Paralichthys californicus es una especie con alto valor comercial debido a su gran tamaño y calidad de su carne. Esta especie presenta dimorfismo sexual en el crecimiento donde las hembras crecen más rápido que los machos, por lo tanto el cultivo monosexual de hembras resulta favorable para la producción. En el presente estudio se registró el proceso de diferenciación sexual mediante cortes histológicos de las larvas y gónadas del lenguado de California asimismo se probó el efecto de diferentes concentraciones de 17β-estradiol (E2) (2.5, 5 y 10 mg/kg) a través de la dieta para incrementar la proporción de hembras en el cultivo. A los 25 días después de la eclosión (DDE) se observó el primordio gonadal en ejemplares con una longitud total promedio de 6.96 ± 0.92 mm, hasta el día 75 DDE (37.58 ± 6.58 mm) se observó una gónada indiferenciada evidenciada por la presencia de células germinales primordiales. La primera evidencia de diferenciación se registró a los 115 DDE (55.93 ± 14.67 mm) donde se observó la cavidad ovárica y posteriormente a los 180 DDE (115.70 ± 17.02 mm) se evidencian ovarios con ovocitos en crecimiento y testículos con espermátidas. Por lo tanto, el periodo lábil para la diferenciación sexual se encuentra entre los días 75 y 115 después de la eclosión. Por otro lado, el suministro de E2 a través de la dieta a concentraciones de 2.5, 5 y 10 mg/kg incrementó el porcentaje de hembras de 26.67% (control, no adición de E2) a un 100% en todos los tratamientos. Se encontraron diferencias en la proporción de los tipos celulares (ovogonias, ovocitos primarios en fase I y II) entre el control y los tratamientos mientras que no se registraron alteraciones histológicas como atrofia gonadal en ninguno de los casos.

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Changes in blood dendritic cell (BDC) counts (CD123(hi)BDC and CD11c(+)BDC) and expression of CD62L, CCR7, and CD49d were analyzed in healthy donors, multiple myeloma (MM), and non-Hodgkin lymphoma (NHL) patients, who received granulocyte-colony stimulating factor (G-CSF) containing peripheral blood stem cell (PBSC) mobilization protocols. Low-dose G-CSF in healthy donors (8-10 mug/ kg/d subcutaneously) and high-dose G-CSF in patients (30 mug/kg/d) increased CD123(hi)BDC (2- to 22-fold, mean 3.7 x 10(6)/ L-17.7 x 10(6)/L and 1.9 x 10(6)/L-12.0 x 10(6)/ L) in healthy donors and MM but decreased CD11c(+)BDC (2- to 10-fold, mean 5.7 x 10(6)/L-1.6 x 10(6)/L) in NHL patients, on the day of apheresis, compared with steady state. After apheresis, CD123(hi)BDC counts remained high, whereas low CD11c(+)BDC counts tended to recover in the following 2-5 days. Down-regulation of CD62L and up-regulation of CCR7 on CD123(hi)BDC were found in most healthy donors and MM patients. CD49d expression was unchanged. Thus, PBSC mobilization may change BDC counts by altering molecules necessary for BDC homing from blood into tissues.

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Immunotherapy strategies aimed at increasing human Valpha24(+)Vbeta11(+) natural killer T (NKT) cell numbers are currently a major focus. To provide further information towards the goal of NKT cell-based immunotherapy, we assessed the effects of age, cancer status and prior anticancer treatment on NKT cell numbers and their expansion capacity following alpha-galactosylceramide (alpha-GalCer) stimulation. The percentage and absolute number of peripheral blood NKT cells was assessed in 40 healthy donors and 109 solid cancer patients ( colorectal ( n = 33), breast ( n = 10), melanoma ( n = 17), lung ( n = 8), renal cell carcinoma ( n = 10), other cancers ( n = 31)). Responsiveness to alpha-GalCer stimulation was also assessed in 28 of the cancer patients and 37 of the healthy donors. Natural killer T cell numbers were significantly reduced in melanoma and breast cancer patients. While NKT numbers decreased with age in healthy donors, NKT cells were decreased in these cancer subgroups despite age and sex adjustments. Prior radiation treatment was shown to contribute to the observed reduction in melanoma patients. Although cancer patient NKT cells were significantly less responsive to alpha-GalCer stimulation, they remained capable of substantial expansion. Natural killer T cells are therefore modulated by age, malignancy and prior anticancer treatment; however, cancer patient NKT cells remain capable of responding to alpha-GalCer-based immenotherapies.

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The uptake and metabolism profiles of ginsenoside Rh2 and its aglycon protopanaxadiol (ppd) were studied in the human epithelial Caco-2 cell line. High-performance liquid chromatography-mass spectrometry was applied to determine Rh2 and its aglycon ppd concentration in the cells at different pH, temperature, concentration levels and in the presence or absence of inhibitors. Rh2 uptake was time and concentration dependent, and its uptake rates were reduced by metabolic inhibitors and influenced by low temperature, thus indicating that the absorption process was energy-dependent. Drug uptake was maximal when the extracellular pH was 7.0 for Rh2 and 8.0 for ppd. Rh2 kinetic analysis showed that a non-saturable component (K-d 0.17 nmol (.) h(-1) (.) mg(-1) protein) and an active transport system with a K-m of 3.95 mumol (.) l(-1) and a V-max of 4.78 nmol(.)h(-1) (.)mg(-1) protein were responsible for the drug uptake. Kinetic analysis of ppd showed a non-saturable component (K-d 0.78 nmol (.) h(-1) (.) mg(-1) protein). It was suggested that active extrusion of P-glycoprotein and drug degradation in the intestine may influence Rh2 bioavailability.

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Australian lungfish Neoceratodus forsteri may be the closest living relative to the first tetrapods and yet little is known about their retinal ganglion cells. This study reveals that lungfish possess a heterogeneous population of ganglion cells distributed in a horizontal streak across the retinal meridian, which is formed early in development and maintained through to adult stages. The number and complement of both ganglion cells and a population of putative amacrine cells within the ganglion cell layer are examined using retrograde labelling from the optic nerve and transmission electron-microscopic analysis of axons within the optic nerve. At least four types of retinal ganglion cells are present and lie predominantly within a thin ganglion cell layer, although two subpopulations are identified, one within the inner plexiform and the other within the inner nuclear layer. A subpopulation of retinal ganglion cells comprising up to 7% or the total population are significantly larger (> 400 mu m(2)) and are characterized as giant or alpha-like cells. Up to 44% of cells within the retinal ganglion cell layer represent a population of presumed amacrine cells. The optic nerve is heavily fasciculated and the proportion of myelinated axons increases with body length from 17% in subadults to 74% in adults. Spatial resolving power, based on ganglion cell spacing, is low (1.6-1.9 cycles deg(-1), n = 2) and does not significantly increase with growth. This represents the first detailed study of retinal ganglion cells in sarcopterygian fish, and reveals that, despite variation amongst animal groups, trends in ganglion cell density distribution and characteristics of cell types were defined early in vertebrate evolution.