Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Front Immunol ; 14: 1203614, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600815

RESUMO

Introduction: Early recovery of donor-derived invariant natural killer T (iNKT) cells are associated with reduced risk of graft-versus-host disease (GvHD) and overall survival. Patients with severe GvHD, however, had much slower iNKT cell reconstitution relative to conventional T cells. Methods: To characterize the delay of iNKT cell reconstitution and explore its possible causes, we used a haploidentical bone marrow transplantation (haplo-BMT) mouse model with GvHD. We found the delayed recovery of thymic and peripheral iNKT cell numbers with markedly decreased thymic NKT1 subset in GvHD mice. The defective generation of thymic iNKT precursors with egress capability contributed to the reduced peripheral iNKT cells in GvHD mice. We further identified intermediate NK1.1- NKT1 precursor subpopulations under steady-state conditions and found that the differentiation of these subpopulations was impaired in the thymi of GvHD mice. Detailed characterization of iNKT precursors and thymic microenvironment showed a close association of elevated TCR/co-stimulatory signaling provided by double positive thymocytes and macrophages with defective down-regulation of proliferation, metabolism, and NKT2 signature in iNKT precursor cells. Correspondingly, NKT2 but not NKT1 differentiation was favored in GvHD mice. Discussion: These data underline the important roles of TCR and co-stimulatory signaling in the differentiation of thymic iNKT subsets under transplantation conditions.


Assuntos
Doença Enxerto-Hospedeiro , Células T Matadoras Naturais , Animais , Camundongos , Transplante de Medula Óssea , Diferenciação Celular , Receptores de Antígenos de Linfócitos T/genética
2.
Cell Mol Immunol ; 17(4): 395-406, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31076725

RESUMO

Thymic natural killer T (NKT)2 cells are a subset of invariant NKT cells with PLZFhiGATA3hiIL-4+. The differentiation of NKT2 cells is not fully understood. In the present study, we report an important role of TRAF3-interacting protein 3 (TRAF3IP3) in the functional maturation and expansion of committed NKT2s in thymic medulla. Mice with T-cell-specific deletion of TRAF3IP3 had decreased thymic NKT2 cells, decreased IL-4-producing peripheral iNKTs, and defects in response to α-galactosylceramide. Positive selection and high PLZF expression in CD24+CD44- and CCR7+CD44- immature iNKTs were not affected. Only CD44hiNK1.1- iNKTs in Traf3ip3-/- mice showed reduced expression of Egr2, PLZF, and IL-17RB, decreased proliferation, and reduced IL-4 production upon stimulation. This Egr2 and IL-4 expression was augmented by MEK1/ERK activation in iNKTs, and TRAF3IP3 at the trans-Golgi network recruited MEK1 and facilitated ERK phosphorylation and nuclear translocation. LTßR-regulated bone marrow-derived nonlymphoid cells in the medullary thymic microenvironment were required for MEK/ERK activation and NKT2 maturation. These data demonstrate an important functional maturation process in NKT2 differentiation that is regulated by MEK/ERK signaling at the trans-Golgi network.


Assuntos
Proteínas de Transporte/metabolismo , Diferenciação Celular , Sistema de Sinalização das MAP Quinases , Proteínas de Membrana/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Células T Matadoras Naturais/citologia , Células T Matadoras Naturais/metabolismo , Rede trans-Golgi/metabolismo , Animais , Proliferação de Células , Microambiente Celular , Ativação Enzimática , Células HEK293 , Humanos , Proteínas de Membrana/deficiência , Camundongos Endogâmicos C57BL , Camundongos Knockout , Timo/citologia
3.
Cell Mol Immunol ; 17(5): 507-518, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31171863

RESUMO

Newborn animals require tightly regulated local and systemic immune environments to govern the development and maturation of multiple organs/tissues even though the immune system itself is far from mature during the neonatal period. Regulatory T cells (Tregs) are essential for maintaining immune tolerance/homeostasis and modulating inflammatory responses. The features of Tregs in the neonatal liver under steady-state conditions are not well understood. The present study aimed to investigate the phenotype, functions, and significance of neonatal Tregs in the liver. We found a wave of thymus-derived Treg influx into the liver during 1-2 weeks of age. Depletion of these Tregs between days 7 and 11 after birth rapidly resulted in Th1-type liver inflammation and metabolic disorder. More Tregs in the neonatal liver than in the spleen underwent MHC II-dependent activation and proliferation, and the liver Tregs acquired stronger suppressive functions. The transcriptomic profile of these neonatal liver Tregs showed elevated expression of PPARγ and T-bet and features of Tregs that utilize lipid metabolic machinery and are capable of regulating Th1 responses. The accumulation of Tregs with unique features in the neonatal liver is critical to ensure self-tolerance and liver maturation.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Tolerância Imunológica , Fígado/imunologia , Linfócitos T Reguladores/imunologia , Animais , Animais Recém-Nascidos , Antígenos de Bactérias/imunologia , Apoptose/genética , Proliferação de Células/genética , Perfilação da Expressão Gênica , Antígenos de Histocompatibilidade Classe II/imunologia , Tolerância Imunológica/genética , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Fígado/patologia , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Camundongos Endogâmicos C57BL , Fenótipo , Baço/patologia
4.
Cell Mol Immunol ; 16(9): 746-756, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-29921968

RESUMO

Invariant natural killer T1 (iNKT1) cells are characterized by the preferential expression of T-box transcription factor T-bet (encoded by Tbx21) and the production of cytokine IFN-γ, but the relationship between the developmental process and iNKT1 lineage diversification in the thymus remains elusive. We report in the present study a crucial role of programmed cell death 5 (PDCD5) in iNKT cell terminal maturation and iNKT1 fate determination. Mice with T cell-specific deletion of PDCD5 had decreased numbers of thymic and peripheral iNKT cells with a predominantly immature phenotype and defects in response to α-galactosylceramide. Loss of PDCD5 also selectively abolished the iNKT1 lineage by reducing T-bet expression in iNKT cells at an early thymic developmental stage (before CD44 upregulation). We further demonstrated that TOX2, one of the high mobility group proteins that was highly expressed in iNKT cells at stage 1 and could be stabilized by PDCD5, promoted the permissive histone H3K4me3 modification in the promoter region of Tbx21. These data indicate a pivotal and unique role of PDCD5/TOX2 in iNKT1 lineage determination. They also suggest that the fate of iNKT1 may be programmed at the developmental stage of iNKT cells in the thymus.


Assuntos
Proteínas Reguladoras de Apoptose/fisiologia , Diferenciação Celular , Regulação da Expressão Gênica , Células T Matadoras Naturais/citologia , Células T Matadoras Naturais/imunologia , Proteínas de Neoplasias/fisiologia , Proteínas com Domínio T/metabolismo , Animais , Linhagem da Célula , Células Cultivadas , Citocinas , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Fenótipo , Proteínas com Domínio T/genética
5.
J Immunol ; 200(3): 1064-1077, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29288207

RESUMO

Mature naive T cells circulate through the secondary lymphoid organs in an actively enforced quiescent state. Impaired cell survival and cell functions could be found when T cells have defects in quiescence. One of the key features of T cell quiescence is low basal metabolic activity. It remains unclear at which developmental stage T cells acquire this metabolic quiescence. We compared mitochondria among CD4 single-positive (SP) T cells in the thymus, CD4+ recent thymic emigrants (RTEs), and mature naive T cells in the periphery. The results demonstrate that RTEs and naive T cells had reduced mitochondrial content and mitochondrial reactive oxygen species when compared with SP thymocytes. This downregulation of mitochondria requires T cell egress from the thymus and occurs early after young T cells enter the circulation. Autophagic clearance of mitochondria, but not mitochondria biogenesis or fission/fusion, contributes to mitochondrial downregulation in RTEs. The enhanced apoptosis signal-regulating kinase 1/MAPKs and reduced mechanistic target of rapamycin activities in RTEs relative to SP thymocytes may be involved in this mitochondrial reduction. These results indicate that the gain of metabolic quiescence is one of the important maturation processes during SP-RTE transition. Together with functional maturation, it promotes the survival and full responsiveness to activating stimuli in young T cells.


Assuntos
Metabolismo Basal/fisiologia , Linfócitos T CD4-Positivos/metabolismo , Mitocôndrias/metabolismo , Timo/citologia , Transferência Adotiva , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/transplante , Proteína Forkhead Box O1/metabolismo , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Espécies Reativas de Oxigênio/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Timo/imunologia
6.
FASEB J ; 31(8): 3695-3709, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28495755

RESUMO

Exposure to microgravity leads to alterations in multiple systems, but microgravity-related changes in the gastrointestinal tract and its clinical significance have not been well studied. We used the hindlimb unloading (HU) mouse model to simulate a microgravity condition and investigated the changes in intestinal microbiota and colonic epithelial cells. Compared with ground-based controls (Ctrls), HU affected fecal microbiota composition with a profile that was characterized by the expansion of Firmicutes and decrease of Bacteroidetes. The colon epithelium of HU mice showed decreased goblet cell numbers, reduced epithelial cell turnover, and decreased expression of genes that are involved in defense and inflammatory responses. As a result, increased susceptibility to dextran sulfate sodium-induced epithelial injury was observed in HU mice. Cohousing of Ctrl mice with HU mice resulted in HU-like epithelial changes in Ctrl mice. Transplantation of feces from Ctrl to HU mice alleviated these epithelial changes in HU mice. Results indicate that HU changes intestinal microbiota, which leads to altered colonic epithelial cell homeostasis, impaired barrier function, and increased susceptibility to colitis. We further demonstrate that alteration in gastrointestinal motility may contribute to HU-associated dysbiosis. These animal results emphasize the necessity of evaluating astronauts' intestinal homeostasis during distant space travel.-Shi, J., Wang, Y., He, J., Li, P., Jin, R., Wang, K., Xu, X., Hao, J., Zhang, Y., Liu, H., Chen, X., Wu, H., Ge, Q. Intestinal microbiota contributes to colonic epithelial changes in simulated microgravity mouse model.


Assuntos
Bactérias/classificação , Colo/patologia , Mucosa Intestinal/microbiologia , Microbiota/fisiologia , Simulação de Ausência de Peso , Animais , Bactérias/genética , Disbiose , Células Epiteliais/fisiologia , Fezes/química , Feminino , Homeostase , Imunoglobulina A/química , Mucosa Intestinal/patologia , Camundongos , Camundongos Endogâmicos C57BL , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Distribuição Aleatória
7.
Toxicol Res (Camb) ; 6(4): 487-498, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30090517

RESUMO

Silica is frequently used in oral drug delivery; however, its biosafety, particularly concerned with its nanostructure, has not been comprehensively studied yet. Here, the in vitro and in vivo biosafety of two types of silica (A200, nano-sized or micron-sized agglomerates; S350, micro-sized particles with nanopores) were compared and the possible reasons for the differences were explored. The results indicated that both A200 and S350 could inhibit the growth of Caco-2 cells by inducing apoptosis and changing the cell cycle progression. A200 showed a stronger influence than S350 in most of the in vitro experiments. In the in vivo study in KM mice, both A200 and S350 could change the blood constituents under the tested conditions; A200 also increased the levels of inflammatory factors in plasma and the numbers of CD4+ lymphocyte subsets. No obvious organic damage was observed in either the A200-treated or S350-treated groups. The transport study showed that neither A200 nor S350 were readily transported across the intestinal epithelial barrier in vitro and in vivo, but A200 could transport across the lymphatic-associated epithelium and accumulate in the Peyer's Patches, which might explain the A200-induced immune response. The increased transport of A200 might relate to its particle size, dispersion state and specific surface area. In conclusion, these results demonstrated that A200 and S350 exhibited diverse biosafety aspects, which correlated with their different nanostructures. We believe this study will provide some scientific information about the biosafety of A200 and S350 for their applications in oral drug delivery systems.

8.
Cytometry A ; 89(9): 844-51, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27560925

RESUMO

High purity chromosome sorting can be performed on instruments such as MoFlo MLS and BD influx, which are stream-in-air sorters equipped with water-cooled high power lasers. The FACSAria is a true fixed alignment, low laser powered instrument with a quartz flow cell gel-coupled to the collection optics. However, whether high purity mouse and human chromosomes can be obtained by sorting on the BD FACSAria(TM) Special Order Research Product (FACSAria SORP) remains to be determined. Here, we report that the high resolution flow karyotype of mouse lymphocytes and normal male human peripheral blood mononuclear cells (hPBMCs) can be obtained on the FACSAria SORP using laser power settings of 50 mW for 355 nm and 20 mW for 444 nm excitation. Furthermore, the use of Fluorescence in situ hybridization (FISH) confirmed that chromosome paints prepared from the sorted chromosomes demonstrated high purity and signal specificity. Notably, human chromosome 12 was separated from the chromosome 9-12 cluster in the flow karyotype, and its identity was confirmed using FISH in trisomy 12 human ES cell lines B2-C7 and B2-B8. In addition, multicolor FISH (mFISH) with human chromosome painting probes to 13,18, 21, and sex chromosomes X and Y showed high signal specificity in hPBMCs. Taken together, our findings demonstrated that high resolution flow karyotype can be obtained using FACSAria SORP. Moreover, a FISH analysis confirmed high purity of the sorted chromosomes. Additionally, in contrast to centromeric satellite probes, chromosome painting probes with high specificity are more suitable for detection of chromosome aberrations, such as deletions and translocations, in prenatal diagnosis. © 2016 International Society for Advancement of Cytometry.


Assuntos
Cromossomos/genética , Citometria de Fluxo/métodos , Hibridização in Situ Fluorescente/métodos , Leucócitos Mononucleares/citologia , Animais , Coloração Cromossômica , Humanos , Cariotipagem , Camundongos
9.
Sci Rep ; 6: 19861, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26794038

RESUMO

The liver is a unique lymphoid organ whose microenvironment is biased towards tolerance induction. We previously found that a proportion of CD4(+) autoreactive recent thymic emigrants (RTEs) retained in the liver after thymic egress and acquired IL-10 producing capability. To investigate the tolerance of these liver persisting CD4(+) RTEs in more detail and to study the liver stromal cell types that facilitate the tolerogenic changes in young T cells, the phenotype and function of liver RTEs were further characterized and the impact of liver sinusoidal endothelial cells (LSECs) and Kupffer cells on RTEs were examined using an in vitro co-culture system. More than 70% of CD4(+) CD44(hi) RTEs in the liver acquired Foxp3(-)LAG3(+) CD49b(-) regulatory phenotype and function. But higher ratio of apoptosis with enhanced FasL and Bim expression was also found in these CD4(+) liver RTEs when compared to those in the lymph nodes and spleen. LSECs played an important role in RTEs' acquisition of tolerogenic and regulatory phenotype. These results indicate an important role of liver microenvironment in enforcing peripheral tolerance to CD4(+) thymic emigrants against self- and gut-derived antigens.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Células Endoteliais/citologia , Tolerância Imunológica , Fígado/citologia , Timo/citologia , Animais , Apoptose , Comunicação Celular , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Receptores Notch/metabolismo , Transdução de Sinais
10.
FASEB J ; 29(8): 3263-73, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25877215

RESUMO

The immune systems can be altered by spaceflight in many aspects, but microgravity-related mucosal immune changes and its clinical significance have not been well studied. The purpose of this study was to investigate whether simulated microgravity influences the intestinal homeostasis and increases the susceptibility to colon inflammation. The hindlimb unloading (HU) mouse model was used to simulate the microgravity condition. Three percent dextran sulfate sodium (DSS) was given to mice to induce colitis. Compared to ground control (Ctrl) mice, the HU ones revealed an impaired intestinal homeostasis and increased susceptibility to DSS-induced colitis. This includes an early-onset, 4-fold expansion of segmented filamentous bacteria (SFB), more than 2-fold decrease in regulatory T (Treg) cell numbers and IL-10 production, ∼2-fold increase in colonic IL-1ß expression, 2-fold increase in circulating neutrophils, and colonic neutrophil infiltration. The application of antibiotics ameliorated the Treg and IL-10 reductions but did not significantly dampen neutrophilia and elevated expression of colonic IL-1ß. These results indicate that the intestinal microflora and innate immune system both respond to simulated microgravity and together, contribute to the proinflammatory shift in the gut microenvironment. The data also emphasize the necessity for evaluating the susceptibility to inflammatory bowel diseases (IBDs) in distant space travels.


Assuntos
Colite/etiologia , Suscetibilidade a Doenças/etiologia , Homeostase/fisiologia , Intestinos/fisiologia , Animais , Colite/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças/metabolismo , Feminino , Inflamação/etiologia , Inflamação/metabolismo , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/metabolismo , Simulação de Ausência de Peso/métodos
11.
J Autoimmun ; 56: 87-97, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25468259

RESUMO

Mechanisms of peripheral tolerance play a critical role in preventing T cells that escape from negative selection in the thymus from initiating autoimmune reactions. To investigate the site of peripheral tolerance induction, we examined migration and activation of recent thymic emigrants (RTEs) in liver, spleen, lymph node and peripheral blood. We show that a fraction of RTE precursors were retained in the liver independent of the secondary lymphoid organs. Compared to RTEs from the lymph nodes, RTEs from the liver proliferated more and many exhibited an activated phenotype with the capability of producing IL-10 upon activation. Liver RTEs also responded poorly to interleukin (IL)-7 and were more prone to apoptosis. Following transfer into RAG(-/-) recipients, liver RTEs induced more severe inflammation and T cell infiltration in the lung and colon. The extrathymic expression of MHC and Aire is required for the acquisition of tolerogenic phenotype of newly generated thymic emigrants in the liver. These results suggest that the liver is the first checkpoint in the periphery to filter, retain, and enforce tolerance to autoreactive CD4(+) thymic emigrants that escape from negative selection.


Assuntos
Autoimunidade , Linfócitos T CD4-Positivos/imunologia , Movimento Celular/imunologia , Tolerância Imunológica , Fígado/imunologia , Subpopulações de Linfócitos T/imunologia , Timócitos/imunologia , Animais , Antígenos de Superfície/metabolismo , Autoimunidade/genética , Linfócitos T CD4-Positivos/metabolismo , Sobrevivência Celular/imunologia , Antígenos de Histocompatibilidade/imunologia , Tolerância Imunológica/genética , Interleucina-10/metabolismo , Interleucina-7/metabolismo , Ativação Linfocitária/imunologia , Camundongos , Camundongos Knockout , Nódulos Linfáticos Agregados/imunologia , Nódulos Linfáticos Agregados/metabolismo , Fenótipo , Subpopulações de Linfócitos T/metabolismo , Timócitos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína AIRE
12.
Biochem Biophys Res Commun ; 447(2): 224-30, 2014 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-24709078

RESUMO

Antitumor antibiotic lidamycin (LDM) is widely used in the treatment of a variety of cancers. Here we demonstrated that LDM up-regulates the expression of the tumor suppressor p53 gene by repressing Oct4 transcription. We showed that low dose LDM-induced increase of p53 expression and decrease of Oct4 expression in P19 and HCT116-p53(+/+) cells. Knockdown of Oct4 expression by siRNA led to activation of p53 in both cell lines, whereas ectopical expression of Oct4 significantly inhibited p53 expression in P19 cells. LDM-induced p53 activation was blocked by ectopical expression of Oct4.


Assuntos
Aminoglicosídeos/farmacologia , Antibióticos Antineoplásicos/farmacologia , Enedi-Inos/farmacologia , Expressão Gênica/efeitos dos fármacos , Fator 3 de Transcrição de Octâmero/genética , Transcrição Gênica/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Animais , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA Interferente Pequeno/genética , Regulação para Cima
13.
Artigo em Inglês | MEDLINE | ID: mdl-24523825

RESUMO

The senescence accelerated mouse prone 8 substrain (SAM-P8), widely accepted as an animal model for studying aging and antiaging drugs, was used to examine the effects of dietary supplementation with extracts of Cistanche deserticola (ECD) which has been used extensively in traditional Chinese medicine because of its perceived ability to promote immune function in the elderly. Eight-month-old male SAM-P8 mice were treated with ECD by daily oral administrations for 4 weeks. The results showed that dietary supplementation of 150 mg/kg and 450 mg/kg of ECD could extend the life span measured by Kaplan-Meier survival analysis in dose-dependent manner. Dietary supplementation of SAM-P8 mice for 4 weeks with 100, 500, and 2500 mg/kg of ECD was shown to result in significant increases in both naive T and natural killer cells in blood and spleen cell populations. In contrast, peripheral memory T cells and proinflammatory cytokine, IL-6 in serum, were substantially decreased in the mice that ingested 100 and 500 mg/kg of ECD daily. Additionally, Sca-1 positive cells, the recognized progenitors of peripheral naive T cells, were restored in parallel. Our results provide clear experimental support for long standing clinical observational studies showing that Cistanche deserticola possesses significant effects in extending life span and suggest this is achieved by antagonizing immunosenescence.

14.
Part Fibre Toxicol ; 10: 47, 2013 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-24088372

RESUMO

BACKGROUND: Nanocarriers represent an attractive means of drug delivery, but their biosafety must be established before their use in clinical research. OBJECTIVES: Four kinds of amphiphilic polymeric (PEG-PG-PCL, PEEP-PCL, PEG-PCL and PEG-DSPE) micelles with similar hydrophilic or hydrophobic structure were prepared and their in vitro and in vivo safety were evaluated and compared. METHODS: In vitro nanotoxicity evaluations included assessments of cell morphology, cell volume, inflammatory effects, cytotoxicity, apoptosis and membrane fluidity. An umbilical vein cell line (Eahy.926) and a kind of macrophages (J774.A1) were used as cell models considering that intravenous route is dominant for micelle delivery systems. In vivo analyses included complete blood count, lymphocyte subset analysis, detection of plasma inflammatory factors and histological observations of major organs after intravenous administration to KM mice. RESULTS: All the micelles enhanced inflammatory molecules in J774.A1 cells, likely resulting from the increased ROS levels. PEG-PG-PCL and PEEP-PCL micelles were found to increase the J774.A1 cell volume. This likely correlated with the size of PEG-PG-PCL micelles and the polyphosphoester structure in PEEP-PCL. PEG-DSPE micelles inhibited the growth of Eahy.926 cells via inducing apoptosis. This might relate to the structure of DSPE, which is a type of phospholipid and has good affinity with cell membrane. No evidence was found for cell membrane changes after treatment with these micelles for 24 h. In the in vivo study, during 8 days of 4 time injection, each of the four nanocarriers altered the hematic phase differently without changes in inflammatory factors or pathological changes in target organs. CONCLUSIONS: These results demonstrate that the micelles investigated exhibit diverse nanotoxicity correlated with their structures, their biosafety is different in different cell model, and there is no in vitro and in vivo correlation found. We believe that this study will certainly provide more scientific understandings on the nanotoxicity of amphiphilic polymeric micelles.


Assuntos
Portadores de Fármacos/toxicidade , Nanopartículas/toxicidade , Poliésteres/toxicidade , Polietilenoglicóis/toxicidade , Tensoativos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocinas/imunologia , Portadores de Fármacos/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Fluidez de Membrana/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos , Micelas , Estrutura Molecular , Nanopartículas/química , Especificidade de Órgãos , Tamanho da Partícula , Poliésteres/química , Polietilenoglicóis/química , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Propriedades de Superfície , Tensoativos/química , Testes de Toxicidade
15.
PLoS One ; 8(10): e77401, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24143230

RESUMO

Spaceflight is associated with deregulation in the immune system. Head-down bed rest (HDBR) at -6° is believed to be the most practical model for examining multi-system responses to microgravity in humans during spaceflight. In the present study, a 45-day HDBR was performed to investigate the alterations in human immune cell distributions and their functions in response to various stimuli. The effect of countermeasure, Rhodiola rosea (RR) treatment, was also examined. A significant decrease of interferon-γ (IFN-γ) and interleukin-17 (IL-17) productions by activated T cells, increase of IL-1ß and IL-18 by activated B and myeloid cells were observed during HDBR. The upregulation of serum cortisol was correlated with the changes of IL-1 family cytokines. In addition, a significant increase of memory T and B cell and regulatory T cells (Treg) were also detected. The uptake of RR further decreased IFN-γ level and slowed down the upregulation of IL-1 family cytokines. These data suggest that for prolonged HDBR and spaceflight, the decreased protective T cell immunity and enhanced proinflammatory cytokines should be closely monitored. The treatment with RR may play an important role in suppressing proinflammatory cytokines but not in boosting protective T cell immunity.


Assuntos
Repouso em Cama , Citocinas/sangue , Cabeça , Voo Espacial , Simulação de Ausência de Peso/métodos , Adulto , Citocinas/biossíntese , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Masculino , Extratos Vegetais/farmacologia , Rhodiola/química
16.
PLoS One ; 8(2): e56378, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23409179

RESUMO

After a tightly regulated developmental program in the thymus, "mature" single positive (SP) thymocytes leave the thymus and enter the periphery. These newly arrived recent thymic emigrants (RTEs) are phenotypically and functionally immature, and will complete a dynamic maturation in the peripheral lymphoid organs before being licensed to be resident naïve T cells. To study the early events occurring in the RTE maturation process, we identified the phenotype of CD4(+) pre-RTEs, a population of CD4(+) SP thymocytes that have acquired the thymus egress capability. Compared to peripheral naïve T cells, CD4(+) pre-RTEs displayed superior survival capability in lymphoreplete mice and faster proliferation under lymphopenic condition. The differences in Bcl2/Bim expression and/or heightened IL-7 signaling pathway may account for the pre-RTEs' better responsiveness to homeostatic signals. Qa2, the expression of which indicates the phenotypic maturation of SPs and RTEs, was found to be upregulated in CD4(+) pre-RTEs in thymic perivascular space. Migratory dendritic cells that surround this region contribute to Qa2 expression in pre-RTEs. The dendritic cell-driven Qa2 induction of CD4(+) pre-RTEs is independent of MHC class II and Aire molecules.


Assuntos
Linfócitos T CD4-Positivos/citologia , Homeostase/imunologia , Fenótipo , Timo/imunologia , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Proliferação de Células , Sobrevivência Celular , Células Dendríticas/citologia , Células Dendríticas/imunologia , Lectinas Tipo C/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/imunologia , Timócitos/citologia , Timócitos/imunologia , Regulação para Cima
17.
Biomaterials ; 34(9): 2277-88, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23290525

RESUMO

Interstitial fluid pressure (IFP) in tumor is much higher than that in normal tissue and it constitutes a great obstacle for the delivery of chemodrugs, which makes it a potential target for cancer therapy. In this study, imatinib, a molecular targeting drug, was loaded in sterically stabilized liposomes (SSL-IMA) to reduce the tumor IFP, in an attempt to deliver more liposomal doxorubicin (SSL-DOX) into tumor tissue. In a mouse B16 melanoma model, intravenous injection of 20 mg/kg SSL-IMA achieved the most reduction of tumor IFP and the effect lasted for at least 50 h with the least hematotoxicity. However, intragastric administration of 100 mg/kg free IMA did not decrease the tumor IFP significantly. Mechanisms of the reduction of tumor IFP by SSL-IMA were proved to be the inhibition of PDGF receptor beta, the inhibition of tumor fibroblasts as well as the anti-angiogenesis effect of SSL-IMA. Then it was demonstrated by in vivo imaging that the decrease of tumor IFP by SSL-IMA led to a more and longer intratumoral distribution of the lipid vehicles. The improved delivery was proved again in the anti-tumor study. The combination of SSL-IMA and SSL-DOX inhibited tumor growth and induced apoptosis of tumor cells the most, at a low dose in which neither SSL-DOX nor SSL-IMA showed obvious anti-tumor efficacy. Since no synergy against B16 cells was found between SSL-IMA and SSL-DOX, it was clear that the improved combinational therapy was basically due to the decrease of tumor IFP by SSL-IMA. In conclusion, reducing tumor IFP by SSL-IMA seems to be a promising strategy to potentiate chemotherapies.


Assuntos
Benzamidas/farmacologia , Doxorrubicina/análogos & derivados , Líquido Extracelular/efeitos dos fármacos , Lipossomos/farmacologia , Piperazinas/farmacologia , Polietilenoglicóis/farmacologia , Pirimidinas/farmacologia , Inibidores da Angiogênese/farmacologia , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Quimioterapia Combinada , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Mesilato de Imatinib , Imuno-Histoquímica , Melanoma Experimental/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Receptor beta de Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo
18.
Biomaterials ; 34(3): 756-64, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23117217

RESUMO

Tumor metastasis accounts for 90% of cancer-associated deaths and is almost inaccessible by chemotherapy, surgical operation or radiotherapy. Here, a tumor metastasis-specific nanocarrier system has been constructed by modification of stealth lipid nanoparticles with a specific peptide ligand. Highly metastatic breast cancer MDA-MB-231 that stably expressed luciferase (MDA-MB-231/Luc) was used as tumor cell model. The nanocarrier was very specific for highly metastatic cancer cells in vitro and could specifically target to cancer metastases foci following systemic administration in vivo by both fluorescence imaging and bioluminescence imaging compared to a passive-targeted system. It greatly facilitated the efficacy of doxorubicin loaded in inhibiting tumor metastasis growth and prolonging the survival time of mice. Importantly, this system was also found to prevent the initiation and progression of tumor metastasis. The tumor metastasis-targeted nanocarriers hold great potential in the treatment of cancer metastasis foci and even for the prevention of tumor metastasis. This study may also provide new strategy in the development of nanomedicine for diagnosis and therapy of tumor metastasis.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Neoplasias da Mama/patologia , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Lipossomos/química , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/secundário , Peptídeos/química , Animais , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/uso terapêutico , Mama/patologia , Linhagem Celular Tumoral , Doxorrubicina/farmacocinética , Doxorrubicina/uso terapêutico , Feminino , Humanos , Lipossomos/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/patologia , Neoplasias Pulmonares/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Peptídeos/metabolismo
19.
Biomaterials ; 33(33): 8451-60, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22940213

RESUMO

Tumor metastasis is responsible for 90% of cancer-associated deaths and highly metastatic cancers are more prone to form metastasis foci and acquire the drug resistance. Here, a nanocarrier system (TMT-LS) has been constructed by modification of stealth liposomes with a metastatic cancer specific peptide, using the unmodified stealth liposomes (LS) as the control. The active targeted nanocarriers presented satisfactory particle size (about 100 nm) and drug release characteristics in vitro. Highly metastatic cancer cells (MDA-MB-435S and MDA-MB-231) and non-metastatic cancer cells (MCF-7) were applied as tumor cell models. The highly metastatic cancer cells were found to endocytose more TMT-LS in a faster way than TS, through a receptor-mediated pathway proved by specific receptor inhibition. Co-localization technique indicated the integrity of nanocarriers in cytoplasm. The significant targeting of TMT-LS to highly metastatic tumors was demonstrated in vivo and ex vivo in an orthotopic model as well as in a double tumor-bearing animal model with both metastatic and non-metastatic tumors in the same mouse. Importantly, the active targeted drug delivery system was found to penetrate deeper into tumor mass and have a longer retention within the malignant tissue. Further, TMT-LS greatly facilitated the efficacy of doxorubicin loaded in terms of inhibiting xenograft tumor growth and inducing cancer cell apoptosis, with only minor side effects. Together, the specific nanocarriers hold great potential in the development of nanomedicine for diagnosis and therapy of metastatic tumor.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Lipossomos/química , Metástase Neoplásica/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Camundongos , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Int J Gynecol Cancer ; 20(3): 316-22, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20375790

RESUMO

INTRODUCTION: LyGDI is an inhibitor of Rho protein activation by blocking its transformation between guanosine 5'-diphosphate- and guanosine 5'-triphosphate-bound states. The aim of this study was to investigate the usefulness of LyGDI as a biomarker for the detection of ovarian cancer, and its specificity and sensitivity were compared with those of cancer antigen 125 (CA125). METHODS: The serum levels of LyGDI were determined by enzyme-linked immunosorbent assay in 42 patients with ovarian disease, including 30 ovarian cancers and 12 benign ovarian lesions, and 76 healthy controls. The expression of LyGDI was also evaluated by immunohistochemical staining in resected ovarian tissues of these patients. RESULTS: The serum LyGDI level of cancers was significantly greater than those of the benign and healthy groups (P = 0.002 and P < 0.0001, respectively), whereas no difference was observed between the benign and control groups (P = 0.889). Based upon receiver operating characteristic curve analysis, LyGDI levels were able to distinguish ovarian cancer from benign ovarian disease (P = 0.0001) and healthy control (P < 0.0001; areas under the receiver operating characteristic curves, 0.876 and 0.833, respectively). For ovarian cancers, 83.3% (25/30) or 80.0% (24/30) was identified by serum LyGDI (> or = 1.5 ng/mL) alone or by CA125 (>35 U/mL) alone. It is of particular importance to note that all cancer patients were identified by use of both markers, and the specificity was 83.3% for the benign group. Moreover, in early-stage cancers, 88.9% (8/9) had elevated serum LyGDI levels as compared with 44.4% (4/9) elevation of CA125 levels (P = 0.125). Immunohistochemical staining confirmed the expression of LyGDI on cancerous epithelial cells other than benign ovarian epithelium. CONCLUSIONS: These results suggest that LyGDI has significant potential as a marker for detection of ovarian cancer in the patients with ovarian enlargement, including detection of early-stage cancers.


Assuntos
Biomarcadores Tumorais/sangue , Inibidores de Dissociação do Nucleotídeo Guanina/sangue , Neoplasias Ovarianas/diagnóstico , Proteínas Supressoras de Tumor/sangue , Adenocarcinoma de Células Claras/sangue , Adenocarcinoma de Células Claras/diagnóstico , Adenocarcinoma Mucinoso/sangue , Adenocarcinoma Mucinoso/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígeno Ca-125/sangue , Estudos de Casos e Controles , Cistadenocarcinoma Seroso/sangue , Cistadenocarcinoma Seroso/diagnóstico , Neoplasias do Endométrio/sangue , Neoplasias do Endométrio/diagnóstico , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/sangue , Ovário/metabolismo , Prognóstico , Sensibilidade e Especificidade , Inibidor beta de Dissociação do Nucleotídeo Guanina rho , Inibidores da Dissociação do Nucleotídeo Guanina rho-Específico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...