Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Exp Cell Res ; 440(1): 114115, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38844260

RESUMO

The process of aging is characterized by structural degeneration and functional decline, as well as diminished adaptability and resistance. The aging kidney exhibits a variety of structural and functional impairments. In aging mice, thinning and graying of fur were observed, along with a significant increase in kidney indices compared to young mice. Biochemical indicators revealed elevated levels of creatinine, urea nitrogen and serum uric acid, suggesting impaired kidney function. Histological analysis unveiled glomerular enlargement and sclerosis, severe hyaline degeneration, capillary occlusion, lymphocyte infiltration, tubular and glomerular fibrosis, and increased collagen deposition. Observations under electron microscopy showed thickened basement membranes, altered foot processes, and increased mesangium and mesangial matrix. Molecular marker analysis indicated upregulation of aging-related ß-galactosidase, p16-INK4A, and the DNA damage marker γH2AX in the kidneys of aged mice. In metabolomics, a total of 62 significantly different metabolites were identified, and 10 pathways were enriched. We propose that citrulline, dopamine, and indoxyl sulfate have the potential to serve as markers of kidney damage related to aging in the future. Phosphoproteomics analysis identified 6656 phosphosites across 1555 proteins, annotated to 62 pathways, and indicated increased phosphorylation at the Ser27 site of Minichromosome maintenance complex component 2 (Mcm2) and decreased at the Ser284 site of heterogeneous nuclear ribonucleoprotein K (hnRNP K), with these modifications being confirmed by western blotting. The phosphorylation changes in these molecules may contribute to aging by affecting genome stability. Eleven common pathways were detected in both omics, including arginine biosynthesis, purine metabolism and biosynthesis of unsaturated fatty acids, etc., which are closely associated with aging and renal insufficiency.


Assuntos
Envelhecimento , Instabilidade Genômica , Rim , Componente 2 do Complexo de Manutenção de Minicromossomo , Animais , Envelhecimento/metabolismo , Envelhecimento/genética , Envelhecimento/patologia , Instabilidade Genômica/genética , Camundongos , Fosforilação , Rim/metabolismo , Rim/patologia , Componente 2 do Complexo de Manutenção de Minicromossomo/metabolismo , Componente 2 do Complexo de Manutenção de Minicromossomo/genética , Camundongos Endogâmicos C57BL , Masculino , Metabolômica/métodos , Dano ao DNA , Multiômica
2.
Heliyon ; 9(11): e21011, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37920504

RESUMO

Aging is associated with gradual changes in liver structure, altered metabolites and other physiological/pathological functions in hepatic cells. However, its characterized phenotypes based on altered metabolites and the underlying biological mechanism are unclear. Advancements in high-throughput omics technology provide new opportunities to understand the pathological process of aging. Here, in our present study, both metabolomics and phosphoproteomics were applied to identify the altered metabolites and phosphorylated proteins in liver of young (the WTY group) and naturally aged (the WTA group) mice, to find novel biomarkers and pathways, and uncover the biological mechanism. Analysis showed that the body weights, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) increased in the WTA group. The grips decreased with age, while the triglyceride (TG) and cholesterol (TC) did not change significantly. The increase of fibrosis, accumulation of inflammatory cells, hepatocytes degeneration, the deposition of lipid droplets and glycogen, the damaged mitochondria, and deduction of endoplasmic reticulum were observed in the aging liver under optical and electron microscopes. In addition, a network of metabolites and phosphorylated proteomes of the aging liver was established. Metabolomics detected 970 metabolites in the positive ion mode and 778 metabolites in the negative ion mode. A total of 150 pathways were pooled. Phosphoproteomics identified 2618 proteins which contained 16621 phosphosites. A total of 164 pathways were detected. 65 common pathways were detected in two omics. Phosphorylated protein heat shock protein HSP 90-alpha (HSP90A) and v-raf murine viral oncogene homolog B1(BRAF), related to cancer pathway, were significantly upregulated in aged mice liver. Western blot verified that protein expression of MEK and ERK, downstream of BRAF pathway were elevated in the liver of aging mice. However, the protein expression of BRAF was not a significant difference. Overall, these findings revealed a close link between aging and cancer and contributed to our understanding of the multi-omics changes in natural aging.

3.
ACS Appl Mater Interfaces ; 15(2): 2901-2910, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36602816

RESUMO

The conventional lithium-ion battery technology relies on the liquid carbonate-based electrolyte solution, which causes excessive side reactions, serious risk of electrolyte leakage, high flammability, and significant safety hazards. In this work, phosphonate-functionalized imidazolium ionic liquid (PFIL) is synthesized and used as a gel polymer electrolyte (GPE) to replace the organic carbonate-based electrolyte solution. The as-prepared ionic liquid-based gel polymer electrolyte (IL-GPE) shows low crystallinity, flame retardance, and excellent electrochemical performance. Thanks to the fast double channel transport of lithium ions in the IL-GPE electrolyte, a high ionic conductivity of 0.48 mS cm-1 and a lithium-ion transference number of 0.37 are exhibited. Symmetrical lithium cells with IL-GPE retain stable cycling even after 3000 h under 0.1 mA cm-2. IL-GPE exhibits good compatibility toward lithium metal, yielding excellent long-term electrochemical kinetic stability. IL-GPE induces the formation of a uniform and robust SEI layer, inhibiting the growth of lithium dendrites and improving the rate performance and cycle stability. Furthermore, Li/LiFePO4 cells exhibit a specific capacity of 63 mA h g-1 after 150 cycles at 5.0 C, with a capacity retention of 90.2%. It is foreseen that this GPE is a promising candidate to enhance the safety of high-performance lithium metal batteries.

4.
J Cell Biochem ; 120(9): 15098-15105, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31131472

RESUMO

There are diverse investigations focused on the therapies of lymphoma. Our research was taken to identify the effects of lentiviral-mediated Smad4 gene silencing on chemosensitivity of human lymphoma cells to adriamycin (ADM) via transforming growth factor ß (TGFß) signaling pathway. Raji/ADM cells were cultured and infected with lentiviral particles Smad4-short hairpin (shRNA) and control-shRNA. Then, the messenger RNA (mRNA) and protein levels of TGFß signaling pathway-related factors (Smad4, Smad3, cyclinE, cyclinD1, and p21) in Raji/ADM cells were determined. The effect of Smad4-shRNA on cell viability, invasion and migration, and apoptosis were also detected. Compared with the Raji group, increased mRNA and protein levels of Smad4, Smad3, cyclinE, cyclinD1, enhanced cell proliferation, migration and invasion as well as decreased mRNA, and protein levels of p21 and cell apoptosis rate were found in the Raji/ADM and control-shRNA groups. However, Smad4 gene silencing resulted in decreased mRNA and protein levels of Smad4, Smad3, cyclinE, and cyclinD1 along with inhibited cell proliferation, migration and invasion but increased expression of p21 together with cell apoptosis. Collectively, Smad4 gene silencing can inhibit the activation of TGFß signaling pathway, thereby enhancing the chemosensitivity of human lymphoma cells to ADM.


Assuntos
Doxorrubicina/uso terapêutico , Inativação Gênica , Linfoma/tratamento farmacológico , Linfoma/genética , Transdução de Sinais , Proteína Smad4/genética , Fator de Crescimento Transformador beta/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Ciclinas/metabolismo , Doxorrubicina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Humanos , Lentivirus/metabolismo , Linfoma/patologia , Invasividade Neoplásica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Smad3/metabolismo , Proteína Smad4/metabolismo
5.
ScientificWorldJournal ; 2014: 620150, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25258727

RESUMO

This paper considers single machine scheduling and due date assignment with setup time. The setup time is proportional to the length of the already processed jobs; that is, the setup time is past-sequence-dependent (p-s-d). It is assumed that a job's processing time depends on its position in a sequence. The objective functions include total earliness, the weighted number of tardy jobs, and the cost of due date assignment. We analyze these problems with two different due date assignment methods. We first consider the model with job-dependent position effects. For each case, by converting the problem to a series of assignment problems, we proved that the problems can be solved in O(n(4)) time. For the model with job-independent position effects, we proved that the problems can be solved in O(n(3)) time by providing a dynamic programming algorithm.


Assuntos
Algoritmos , Eficiência , Modelos Teóricos , Gerenciamento do Tempo/métodos , Simulação por Computador , Humanos , Reprodutibilidade dos Testes , Fatores de Tempo
7.
Neuro Endocrinol Lett ; 28(6): 775-80, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18063935

RESUMO

The expression of vascular endothelial growth factor receptor 1(VEGFR-1) in human multiple myeloma KM3 cells in vitro, effects of valproic acid (VPA), as a histone deacetylase inhibitor, on cell proliferation and apoptosis and the underlying molecular mechanism were investigated. The effects of VPA on the growth of KM3 cells were studied by MTT assay. The apoptosis rate was determined with flow cytometry. The mRNA level of VEGFR was determined by RT-PCR; and immunocytochemistry was used to detect the protein level of ac-H4 and VEGFR. VPA inhibited proliferation of KM3 cells in a time- and dose-dependent manner. Treatment with VPA (4, 2, 1 and 0.5 mmol/L) for 48h, the apoptosis rates of KM3 cells were (13.27+/-3.54)%, (22.13+/-1.20)%, (24.41+/-2.23)% and(40.62+/-4.28)% respectively. The expression of VEGFR-1 in KM3 cells were decreased in VPA-treated group by the immunochemistry and RT-PCR, whereas the acetylated histone H4(ac-H4) accumulated. It suggested VPA could decrease the expression of VEGFR-1 in KM3 cells, and it might play an important role in regulating the proliferation and apoptosis of multiple myeloma cell line KM3 cells. These results provide the framework for clinical trials.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Mieloma Múltiplo/metabolismo , Ácido Valproico/farmacologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Acetilação/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo , Inibidores de Histona Desacetilases , Histonas/metabolismo , Humanos , Imuno-Histoquímica , Mieloma Múltiplo/tratamento farmacológico , RNA Mensageiro/análise , Fatores de Tempo , Células Tumorais Cultivadas , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/efeitos dos fármacos , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética
8.
Zhonghua Yi Xue Za Zhi ; 84(11): 932-6, 2004 Jun 02.
Artigo em Chinês | MEDLINE | ID: mdl-15329282

RESUMO

OBJECTIVE: To investigate the feasibility of using dendritic cell (DC)-beads-antigen (Ag) as novel cancer vaccine form with E7 as the target antigen. METHODS: C57BL/6 mouse was killed and the femora were taken out. Marrow cells were isolated and cultured with IL-3 and granulocyte-macrophage growth stimulating factor (GM-CSF) so as to prepare DCs. Flow cytometry was conducted to analyze the phenotype. FITC-labeled polystyrene beads-ovalbumin (OVA) or polystyrene beads-human papillomavirus (HPV) E7 protein were added into the culture fluid to be co-cultured with the DCs for 3 hours. Flow cytometry was conducted to analyze the up-taking rates of polystyrene beads-OVA and of polystyrene beads-HPV E7 protein by the DCs and B3Z T cell hybridoma cells were co-cultured and then beads-OVA or beads-SIIFEKL polypeptide was added into the culture fluid. The absorbance was read. Twelve mice were injected with DC-beads-OVA, DC-beads-E7, DC-OVA antigen epitope (SIIFEKL), or DC-E7 epitope (RAHYNIVTF) into the plantae and killed in 36 hours to take out the iliac lymph nodes. Flow cytometry was conducted to analyze the phenotypes of the bead-positive cells. Mice were killed 10 days after immunization and their heart blood was collected. Enzyme linked immunosorbent assay was used to detect the levels of antibodies. Immunized and non-immunized mice were killed and their spleens were taken out. ELISPOT was used to detect the number of cells secreting interferon (IFN)gamma. RESULTS: DCs were seen in the culture fluid of mice marrow cells 5 days after culture with IL-3 and GM-CSF. The bead-positive rates of bead-E7 and bead-OVA were 64% +/- 18% and 58% +/- 16% respectively (P > 0.05) in the IL-3DCs. The CD40 expression rate in the bead-positive cells in the graining iliac lymph nodes was significantly higher after feeding by beads-E7 in comparison with that before the feeding (P < 0.05), the NLDC145, and MHC-II expression rates were increased to a certain degree, however the F4/80 expression rate was decreased. The DCs fed with bead-OVA or with OVA antigen epitope SIIFEKL, especially the former, significantly activated the B3Z cells. The serum IgG level in the mice immunized by beads-E7 was significantly increases, the IgM level was increased slightly, however, the IgA level almost remained unchanged. The numbers of IFNgamma SFU in the splenic cells of the mice immunized by DC-bead-OVA and DC-bead-E7 were significantly higher than that in the unimmunized mice, especially those immunized by DC-bead-OVA. CONCLUSION: DCs fed with beads-E7 can migrate to the draining lymph nodes and induce high level humeral and cellular immunity. DC-beads-Ag seems better than DC-epitope according to the strength of induced immunity. DC-beads-Ag may be an ideal vaccine form and can be used to develop other cancer vaccine.


Assuntos
Células da Medula Óssea/citologia , Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Proteínas Oncogênicas Virais/imunologia , Animais , Formação de Anticorpos/imunologia , Células da Medula Óssea/imunologia , Vacinas Anticâncer/síntese química , Técnicas de Cocultura , Citotoxicidade Imunológica , Células Dendríticas/transplante , Epitopos/imunologia , Técnicas de Transferência de Genes , Imunidade Celular/imunologia , Interleucina-3/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Papillomaviridae/imunologia , Proteínas E7 de Papillomavirus , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/imunologia , Infecções Tumorais por Vírus/complicações , Infecções Tumorais por Vírus/imunologia
9.
J Immunol ; 173(2): 932-44, 2004 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15240680

RESUMO

Adenosine is a purine nucleoside with immunosuppressive activity that acts through cell surface receptors (A(1), A(2a), A(2b), A(3)) on responsive cells such as T lymphocytes. IL-2 is a major T cell growth and survival factor that is responsible for inducing Jak1, Jak3, and STAT5 phosphorylation, as well as causing STAT5 to translocate to the nucleus and bind regulatory elements in the genome. In this study, we show that adenosine suppressed IL-2-dependent proliferation of CTLL-2 T cells by inhibiting STAT5a/b tyrosine phosphorylation that is associated with IL-2R signaling without affecting IL-2-induced phosphorylation of Jak1 or Jak3. The inhibitory effect of adenosine on IL-2-induced STAT5a/b tyrosine phosphorylation was reversed by the protein tyrosine phosphatase inhibitors sodium orthovanadate and bpV(phen). Adenosine dramatically increased Src homology region 2 domain-containing phosphatase-2 (SHP-2) tyrosine phosphorylation and its association with STAT5 in IL-2-stimulated CTLL-2 T cells, implicating SHP-2 in adenosine-induced STAT5a/b dephosphorylation. The inhibitory effect of adenosine on IL-2-induced STAT5a/b tyrosine phosphorylation was reproduced by A(2) receptor agonists and was blocked by selective A(2a) and A(2b) receptor antagonists, indicating that adenosine was mediating its effect through A(2) receptors. Inhibition of STAT5a/b phosphorylation was reproduced with cell-permeable 8-bromo-cAMP or forskolin-induced activation of adenylyl cyclase, and blocked by the cAMP/protein kinase A inhibitor Rp-cAMP. Forskolin and 8-bromo-cAMP also induced SHP-2 tyrosine phosphorylation. Collectively, these findings suggest that adenosine acts through A(2) receptors and associated cAMP/protein kinase A-dependent signaling pathways to activate SHP-2 and cause STAT5 dephosphorylation that results in reduced IL-2R signaling in T cells.


Assuntos
Adenosina/metabolismo , AMP Cíclico/metabolismo , Proteínas de Ligação a DNA/metabolismo , Interleucina-2/metabolismo , Proteínas do Leite , Receptores A2 de Adenosina/metabolismo , Linfócitos T/metabolismo , Transativadores/metabolismo , Animais , Divisão Celular , Feminino , Janus Quinase 1 , Janus Quinase 3 , Camundongos , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Proteínas Tirosina Quinases/metabolismo , Fator de Transcrição STAT5
10.
Zhonghua Xue Ye Xue Za Zhi ; 25(4): 209-12, 2004 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-15182557

RESUMO

OBJECTIVE: To investigate the expression of T cell early activation marker (CD(69)) on peripheral CD(4)(+) and CD(8)(+) lymphocytes and serum levels of soluble tumor necrosis factor receptor 1 and 2 (sTNF-R1 and sTNF-R2) in serum and bone marrow in patients with aplastic anemia (AA) and their pathophysiological significance. METHODS: In vitro activation of T lymphocytes was carried out by whole blood cell culture containing PHA (20 micro g/ml). The CD(69) expressions on CD(4)(+) and CD(8)(+) lymphocytes at 0 h and 4 h after PHA exposure were analyzed by two-color flow cytometry. The levels of sTNF-R1 and sTNF-R2 in serum and bone marrow were measured by ELISA. RESULTS: The CD(69) expression rates of CD(4)(+) and of CD(8)(+) cells in SAA patients were (8.96 +/- 7.23)% and (10.67 +/- 7.58)%, respectively, and that of CD(8)(+) cells in CAA patients was (7.36 +/- 5.49)% before PHA stimulation. The CD(69) expression rates of CD(4)(+) and of CD(8)(+) cells in SAA patients were (71.73 +/- 11.91)% and (61.74 +/- 13.44)% and in CAA (59.35 +/- 10.15)% and (48.78 +/- 8.25)% respectively, and were significantly elevated after PHA stimulation. CD(69) expression on CD(4)(+) cells was much higher than that on CD(8)(+) cells after stimulation. The levels of the two sTNF-R (sTNF-R1 and sTNF-R2) in peripheral blood and bone marrow of SAA patients were elevated and in the bone marrow of CAA patients were also increased. The serum levels of sTNF-R2 were positively related to the CD(69) expression rates of CD(8)(+) cells before PHA stimulation. CONCLUSION: Increased early activation and activated potentials of T lymphocytes, along with abnormally elevated immunologically active molecules might play a major role in the pathogenesis of AA.


Assuntos
Anemia Aplástica/imunologia , Antígenos CD/sangue , Antígenos de Diferenciação de Linfócitos T/sangue , Linfócitos T CD4-Positivos/química , Linfócitos T CD8-Positivos/química , Receptores do Fator de Necrose Tumoral/sangue , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Lectinas Tipo C , Masculino , Pessoa de Meia-Idade , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 12(2): 220-3, 2004 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-15157338

RESUMO

Waldenström's macroglobulinemia (WM) is one of malignant hematological disease on account of abnormal proliferation of B lymphocyte clone and the pathologic cells of WM possess ability to secrete monoclonal immunoglobulin M. In this study, the diagnosis and morphological characteristics of 2 patients with WM were analyzed. The results showed that a special kind of "foam cells" were found by cytochemical staining examinations in both cases, which displayed characteristics of lymphocytes, but neither monocyte-macrophage nor fatty cells. The periodic acid-Shiff's reaction (PAS) demonstrated strong positive, especially on the inclusion bodies in pathologic cell plasma while the acid phosphatase, and alpha-butanoic acetate esterase stainings, resulted both in negative. In conclusion, the cells found in the two cases reported may be described as gemmy ring-like lymphocyte in morphology, a special subtype of ring-like lymphocyte.


Assuntos
Macroglobulinemia de Waldenstrom/patologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade
12.
Eur J Haematol ; 70(6): 353-7, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12756016

RESUMO

The treatment of chronic idiopathic thrombocytopenic purpura (ITP) is difficult in those unresponsive to corticosteroids and/or splenectomy. We attempted to induce durable response in 21 patients with refractory ITP by applying mycophenolate mofetil (MMF) (1.5-2.0 g/d), a novel immunosuppressive agent. Overall response rate was 62% (13 of 21), including 24% (five of 21) in complete response (CR), 29% (six of 21) in partial response (PR), and 10% (two of 21) in minor response (MR). The response rates for non-splenectomized and splenectomized ITP patients were 64% (nine of 14) and 57% (four of seven), respectively (P > 0.05). 39% (five of 13) responders relapsed as a result of dose reduction or withdraw of MMF, and 61% (eight of 13) responders maintained their effectiveness for a median of 24 wk. Sustained response was observed in three patients in whom MMF was withdrawn. MMF was well tolerated with only slight nausea and diarrhea recorded in 3 of 21 cases. No premature withdrawal was found in this study. CD3+ peripheral blood mononuclear cells (PBMC) and CD19+ PBMC were significantly reduced 12 wk after MMF administration in the responders. Platelet-associated antibodies against glycoproteins GPIIb/IIIa were detected in 13 of 21 (62%) patients before MMF treatment, and antibody levels were significantly decreased in responders 12 wk after MMF administration. This suggested that MMF might correct the immunologic abnormalities underlying the destruction of circulating platelets in ITP. We conclude that MMF could be used as a second-line agent for the treatment of steroid-resistant ITP before or after splenectomy and thereby is worth of further evaluation in randomized studies.


Assuntos
Imunossupressores/administração & dosagem , Ácido Micofenólico/administração & dosagem , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Adulto , Idoso , Autoanticorpos/análise , Resistência a Medicamentos , Feminino , Humanos , Imunossupressores/farmacologia , Leucócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/farmacologia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/imunologia , Prednisona/uso terapêutico , Púrpura Trombocitopênica Idiopática/cirurgia , Indução de Remissão , Esplenectomia
13.
Cancer Immunol Immunother ; 52(3): 185-93, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12649748

RESUMO

Paclitaxel and vinblastine are drugs with anti-microtubule activity that are commonly used in the treatment of numerous types of cancer. In this study, we investigated the effect of prior exposure to submaximal cytotoxic concentrations (EC(25) and EC(50)) of paclitaxel or vinblastine on the subsequent susceptibility of surviving P815 murine mastocytoma cells to cytolysis by major histocompatibility complex (MHC)-unrestricted mouse cytotoxic T lymphocytes that had been induced with anti-CD3 antibody. P815 cells that had survived culture for 24 h in the presence of paclitaxel (5 or 50 micro g/ml) or vinblastine (1.5 or 15 micro g/ml) were rendered resistant to anti-CD3-activated killer-T (AK-T) cell-mediated cytolysis in a standard (51)Cr-release assay. Resistance to killing was associated with a reduced ability of AK-T cells to form conjugates with drug-treated P815 target cells, suggesting a possible effect on adhesion molecules. Flow cytometric analysis of paclitaxel- or vinblastine-treated P815 cells revealed reduced cell-surface expression of the adhesion molecules LFA-1 (CD11a /CD18) and ICAM-1 (CD54). Similar results were obtained following paclitaxel or vinblastine treatment of Yac-1 lymphoma cells. RT-PCR analysis revealed reduced levels of mRNAs coding for CD11a and CD54 in paclitaxel- or vinblastine-pretreated P815 cells. Collectively, these data lead us to conclude that paclitaxel and vinblastine render P815 mastocytoma cells resistant to T cell-mediated cytotoxicity by interfering with CD11a and CD54 expression by the tumor cells. A similar effect by these drugs on tumor cells and/or leukocytes in cancer patients might compromise tumor-specific cell-mediated immune responses.


Assuntos
Antígeno CD11a/biossíntese , Complexo CD3/metabolismo , Regulação para Baixo , Imunoterapia/métodos , Molécula 1 de Adesão Intercelular/biossíntese , Paclitaxel/farmacologia , Linfócitos T Citotóxicos/imunologia , Vimblastina/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Radioisótopos de Cromo/uso terapêutico , Citometria de Fluxo , Células Matadoras Naturais/imunologia , Mastocitoma/terapia , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T Citotóxicos/citologia , Fatores de Tempo , Células Tumorais Cultivadas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...