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1.
Purinergic Signal ; 20(1): 73-82, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37055675

RESUMO

Plasmacytoid dendritic cells (pDCs) are a specialized DC subset mainly associated with sensing viral pathogens and high-type I interferon (IFN-I) release in response to toll-like receptor (TLR)-7 and TLR-9 signaling. Currently, pDC contribution to inflammatory responses is extensively described; nevertheless, their regulatory mechanisms require further investigation. CD39 and CD73 are ectoenzymes driving a shift from an ATP-proinflammatory milieu to an anti-inflammatory environment by converting ATP to adenosine. Although the regulatory function of the purinergic halo CD39/CD73 has been reported in some immune cells like regulatory T cells and conventional DCs, its presence in pDCs has not been examined. In this study, we uncover for the first time the expression and functionality of the purinergic halo in human blood pDCs. In healthy donors, CD39 was expressed in the cell surface of 14.0 ± 12.5% pDCs under steady-state conditions, while CD73 showed an intracellular location and was only expressed in 8.0 ± 2.2% of pDCs. Nevertheless, pDCs stimulation with a TLR-7 agonist (R848) induced increased surface expression of both molecules (43.3 ± 23.7% and 18.6 ± 9.3%, respectively), as well as high IFN-α secretion. Furthermore, exogenous ATP addition to R848-activated pDCs significantly increased adenosine generation. This effect was attributable to the superior CD73 expression and activity because blocking CD73 reduced adenosine production and improved pDC allostimulatory capabilities on CD4 + T cells. The functional expression of the purinergic halo in human pDCs described in this work opens new areas to investigate its participation in the regulatory pDC mechanisms in health and disease.


Assuntos
Adenosina , Linfócitos T CD4-Positivos , Humanos , Adenosina/metabolismo , Transdução de Sinais , Trifosfato de Adenosina/metabolismo , Células Dendríticas/metabolismo
2.
J Mater Sci Mater Med ; 25(10): 2229-36, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24573458

RESUMO

Magnetic materials, which have the potential for application in heating therapy by hyperthermia, were prepared. This alternative treatment is used to eliminate cancer cells. Magnetite, magnesium-calcium ferrites and manganese-calcium ferrites were synthesized by sol-gel method followed by heat treatment at different temperatures for 30 min in air. Materials with superparamagnetic behavior and nanometric sizes were obtained in all the cases. Thus, these nanopowders may be suitable for their use in human tissue. The average sizes were 14 nm for magnetite, 10 nm for both Mg(0.4)Ca(0.6)Fe(2)O(4) and Mg(0.6)Ca(0.4)Fe(2)O(4) and 11 nm for Mn(0.2)Ca(0.8)Fe(2)O(4). Taking into account that the Mg(0.4)Ca(0.6)Fe(2)O(4) and Mg(0.6)Ca(0.4)Fe(2)O(4) treated at 350 °C showed the lower coercivity values, these nanoparticles were selected for heating tests and cell viability. Heating curves of Mg(0.4)Ca(0.6)Fe(2)O(4) subjected to a magnetic field of 195 kHz and 10 kA/m exhibited a temperature increase up to 45 °C in 15 min. A high human osteosarcoma cell viability of 90-99.5% was displayed. The human osteosarcoma cell with magnesium-calcium ferrites exposed to a magnetic field revealed a death cell higher than 80% in all the cases.


Assuntos
Compostos Férricos/química , Óxido Ferroso-Férrico/química , Hipertermia Induzida/instrumentação , Fenômenos Magnéticos , Nanopartículas/química , Cálcio/química , Sobrevivência Celular , Células Cultivadas , Humanos , Compostos de Magnésio/química , Magnetismo/instrumentação , Magnetismo/métodos , Compostos de Manganês/química , Teste de Materiais , Nanopartículas/uso terapêutico
3.
Scand J Immunol ; 64(6): 668-76, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17083624

RESUMO

Dendritic cells (DC) play a dual role in the immune response, participating in its induction, and the maintenance of immune tolerance. The aim of this work was to perform a quantitative and phenotypic analysis of DC generated in vitro in the presence of IL-10 in patients with systemic lupus erythematosus (SLE). Blood samples were obtained from 10 active and untreated patients with SLE and six controls. Monocyte-derived DC were generated in vitro in the presence or absence of IL-10, and a quantitative and phenotypic analysis was performed. We found that freshly isolated monocytes from SLE patients had an increased expression of CD11b. On the other hand, the efficiency of in vitro DC generation was diminished in blood samples from SLE patients for conventional DC, but not for IL-10-treated DC. A diminished expression of HLA-DR, CD9 and CD86 was observed in conventional DC from SLE patients compared with controls. In contrast, enhanced levels of HLA-DR, CD80, CD9 and CD151 tetraspanins, FN1 (a class II MHC-tetraspanin epitope), CD85j/ILT2 and CD69 were detected in IL-10-treated DC from SLE patients. Accordingly, the phenotypic profile of IL-10-treated DC was very different in SLE and controls. However, the synthesis of IL-10 and IL-12 was similar in IL-10-treated and conventional cells in both SLE patients and controls. Our findings on the aberrant phenotype of IL-10-treated DC in SLE and their normal efficiency of in vitro generation may be important for the design of future therapies of this condition based on the administration of DC to induce immune tolerance.


Assuntos
Antígenos CD/análise , Células Dendríticas/química , Células Dendríticas/efeitos dos fármacos , Antígenos HLA-DR/análise , Interleucina-10/farmacologia , Lúpus Eritematoso Sistêmico/imunologia , Adulto , Diferenciação Celular , Células Dendríticas/imunologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/química , Monócitos/citologia , Fenótipo , Receptores de Superfície Celular/análise
4.
Lab Anim ; 40(1): 87-95, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16460593

RESUMO

The present study was performed to optimize a superovulation protocol in rats in order to produce a large number of good-quality embryos suitable to develop rat embryonic stem (rES) cells. We first evaluated the ovulation kinetics of three rat strains: Wistar, Fisher and ACI/N. Animals (n=30 per strain) were treated with 50 IU of pregnant mare serum gonadotrophin (PMSG), and ovulation was induced with 50 IU of human chorionic gonadotrophin (hCG) 50 h apart. Next, we evaluated the dose-response curves of PMSG and hCG in Wistar rats in order to obtain the highest number of embryos. The parameters evaluated for superovulation efficiency were: percentage of mated females, percentage of pregnant females and the average number of embryos collected per female. The results of these experiments suggested that the best dose combination was 50 IU for each hormone. Subsequent experiments, again with Wistar rats, were designed to test which of four hormonal combination treatments (30/30, 30/50, 50/30, and 50/50 IU of PMSG/hCG) will produce the largest numbers of good-quality embryos. Embryo quality was evaluated by embryo development uniformity, embryo morphology, embryo survival in an in vitro culture and embryo ability to generate rES-like cells. Results from these experiments showed that 30/50 IU of PMSG/hCG was the treatment that induced the best embryo quality. In conclusion, our results indicated that, in Wistar rats, the most appropriate hormonal combination dose for superovulation protocols with high number of good-quality embryos was 30 IU of PMSG and 50 IU of hCG given 50 h apart. We are performing further studies with rES-like cells produced with the present methodology to evaluate if they are able to participate in the production of germ-line chimeras.


Assuntos
Criação de Animais Domésticos/normas , Gonadotropina Coriônica/farmacologia , Embrião de Mamíferos/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Gonadotropinas Equinas/farmacologia , Superovulação/efeitos dos fármacos , Criação de Animais Domésticos/métodos , Animais , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Embrião de Mamíferos/fisiologia , Desenvolvimento Embrionário/fisiologia , Feminino , Técnicas In Vitro , Gravidez , Ratos , Ratos Endogâmicos F344 , Ratos Wistar , Superovulação/fisiologia
5.
Arch Virol ; 148(12): 2307-23, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14648288

RESUMO

Monocytes-macrophages, the target cells of African swine fever virus (ASFV) are highly heterogeneous in phenotype and function. In this study, we have investigated the correlation between the phenotype of specific populations of porcine macrophages and their permissiveness to ASFV infection. Bone marrow cells and fresh blood monocytes were less susceptible to in vitro infection by ASFV than more mature cells, such as alveolar macrophages. FACS analyses of monocytes using a panel of mAbs specific for porcine monocyte/macrophages showed that infected cells had a more mature phenotype, expressing higher levels of several macrophage specific markers and SLA II antigens. Maturation of monocytes led to an increase in the percentage of infected cells, which correlated with an enhanced expression of CD163. Separation of CD163+ and CD163- monocytes demonstrated the specific sensitivity of the CD163+ subset to ASFV infection. In vivo experiments also showed a close correlation between CD163 expression and virus infection. Finally, mAb 2A10 and, in a lower extent, mAb 4E9 were able to inhibit, in a dose-dependent manner, both ASFV infection and viral particle binding to alveolar macrophages. Altogether, these results strongly suggest a role of CD163 in the process of infection of porcine monocytes/macrophages by ASFV.


Assuntos
Antígenos CD/fisiologia , Antígenos de Diferenciação Mielomonocítica/fisiologia , Asfarviridae/fisiologia , Macrófagos/virologia , Monócitos/virologia , Receptores de Superfície Celular/fisiologia , Animais , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Células Cultivadas , Macrófagos/química , Monócitos/química , Fenótipo , Receptores de Superfície Celular/análise , Suínos
6.
Int Immunol ; 13(12): 1571-81, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11717198

RESUMO

Experimental protocols for cancer immunotherapy include the utilization of autologous monocyte-derived dendritic cells (moDC) pulsed with tumor antigens. However, disease can alter the characteristics of monocyte precursors and some patients have increased numbers (up to 40%) of the minor CD16(+) monocyte subpopulation, which in healthy individuals represent 10% of blood monocytes. At the present, the capacity of CD16(+) monocytes to differentiate into DC has not been evaluated. Here, we investigated the ability of CD16(+) monocytes cultured with granulocyte- macrophage colony-stimulating factor, IL-4 and tumor necrosis factor-alpha to generate DC in vitro, and we compared them to DC derived from regular CD16(-) monocytes. Both monocyte subsets gave rise to cells with DC characteristics. They internalized soluble and particulate antigens similarly, and both were able to stimulate T cell proliferation in autologous and allogeneic cultures. Nevertheless, CD16(+) moDC expressed higher levels of CD86, CD11a and CD11c, and showed lower expression of CD1a and CD32 compared to CD16(-) moDC. Lipopolysaccharide-stimulated CD16(-) moDC expressed increased levels of IL-12 p40 mRNA and secreted greater amounts of IL-12 p70 than CD16(+) moDC, whereas levels of transforming growth factor-beta1 mRNA were higher on CD16(+) moDC. Moreover, CD4(+) T cells stimulated with CD16(+) moDC secreted increased amounts of IL-4 compared to those stimulated by CD16(-) moDC. These data demonstrate that both moDC are not equivalent, suggesting either that they reach different stages of maturation during the culture or that the starting monocytes belong to cell lineages with distinct differentiation capabilities.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Ativação Linfocitária/imunologia , Monócitos/citologia , Monócitos/imunologia , Receptores de IgG/biossíntese , Receptores de IgG/sangue , Autoantígenos/imunologia , Diferenciação Celular/imunologia , Separação Celular , Células Cultivadas , Citocinas/biossíntese , Células Dendríticas/metabolismo , Dextranos/imunologia , Dextranos/metabolismo , Humanos , Imunofenotipagem , Isoantígenos/imunologia , Lipopolissacarídeos/farmacologia , Teste de Cultura Mista de Linfócitos , Monócitos/metabolismo , Fagocitose , Zimosan/imunologia , Zimosan/metabolismo
7.
Rev. esp. pediatr. (Ed. impr.) ; 57(5): 397-402, sept. 2001.
Artigo em Es | IBECS | ID: ibc-542

RESUMO

Se realizó un estudio descriptivo con el objetivo de conocer el comportamiento de algunos factores de riesgo del bajo peso al nacer, en un universo de 74 madres de niños nacidos con peso inferior a 2.500 gramos, pertenecientes al municipio Guáimaro, Camagüey, en el período comprendido entre enero de 1995 y diciembre de 1999. El carné de atención prenatal, el libro de patios y la historia clínica individual constituyeron la fuente primaria de datos, los que se registraron en una encuesta coaccionada al efecto por el autor. Las variables objeto de estudio fueron: edad materna, hábito de fumar, mala nutrición por defecto, antecedentes de hijos con bajo peso, abortos provocados, presencia de embarazo gemelar y afecciones asociadas al embarazo como hipertensión arterial, anemia, incompetencia cervical e infección vaginal. Los principales resultados encontrados fueron: la infección vaginal durante el embarazo se presentó en el 47,3 por ciento de las madres, la mala nutrición materna por defecto en el 37,8 por ciento y el antecedente de abortos provocados en el 32,4 por ciento. Los restantes factores de riesgo analizados se comportaron de la siguiente forma: en el 29,7 por ciento de las madres estuvo presente la anemia durante la gestación, el 24,3 por ciento de las madres fumaron en el embarazo, en el 17,5 por ciento de las madres la edad fue de hasta 19 y 35 años o más y el 14,8 por ciento de las mujeres tuvieron hijos con bajo peso en partos anteriores. Los factores de riesgo de bajo peso al nacer más frecuentemente identificados en fueron: la infección vaginal durante el embarazo, los antecedentes de abortos provocados y la mala nutrición maternal. Los otros factores de riesgo se presentaron con menor frecuencia (AU)


Assuntos
Gravidez , Humanos , Recém-Nascido , Feminino , Recém-Nascido de Baixo Peso , Fatores de Risco
8.
J Comput Assist Tomogr ; 17(3): 495-7, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8491921

RESUMO

A case of Ramsay-Hunt syndrome has been studied with pre- and postcontrast MR imaging, using a three-dimensional Fourier transform fast imaging with steady precession sequence with axially oriented sections and coronal reformatted images. A clear demonstration of the abnormal enhancement of the labyrinth and of the intratemporal cranial nerves was obtained. This demonstration assisted us in establishing the diagnosis of Ramsay-Hunt syndrome.


Assuntos
Herpes Zoster da Orelha Externa/diagnóstico , Imageamento por Ressonância Magnética , Adulto , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Imageamento por Ressonância Magnética/métodos , Compostos Organometálicos , Ácido Pentético
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