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1.
Eur J Immunol ; 29(11): 3485-95, 1999 11.
Artigo em Inglês | MEDLINE | ID: mdl-10556803

RESUMO

The factors mediating recruitment of immune T cells to challenge sites during contact hypersensitivity (CHS) responses remain unclear. To investigate the role of chemokines during elicitation of CHS, the temporal expression of chemokine genes in hapten-challenged ears was tested. KC (the murine homologoue of Groalpha) was expressed 30 min following hapten challenge in naive and hapten-sensitized mice. A rabbit KC-specific antiserum inhibited elicitation of CHS when administered to sensitized mice prior to hapten challenge. Injecting either neutrophils or immune CD8(+) T cells into the ear tissue of immune animals before hapten challenge circumvented the KC antiserum-mediated inhibition of CHS. Neutrophil depletion also inhibited CHS and was circumvented by injecting either neutrophils or hapten-primed CD8(+) T cells into ears of sensitized mice followed by specific hapten challenge. These results indicate that KC-directed neutrophil infiltration of hapten challenge sites is required for elicitation of CHS and suggest that neutrophils mediate recruitment of the hapten-specific CD8(+) T cells that subsequently produce cytokines mediating the hypersensitivity response.


Assuntos
Quimiocinas CXC , Fatores Quimiotáticos/imunologia , Dermatite Alérgica de Contato/imunologia , Substâncias de Crescimento/imunologia , Peptídeos e Proteínas de Sinalização Intercelular , Neutrófilos/imunologia , Animais , Células Cultivadas , Quimiocina CXCL1 , Fatores Quimiotáticos/biossíntese , Substâncias de Crescimento/biossíntese , Haptenos/imunologia , Queratinócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Coelhos
2.
Glycoconj J ; 15(1): 37-49, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9530955

RESUMO

The MUC1 glycoprotein, epitectin, a component of the human bladder epithelium, was purified from human urine. Sedimentation equilibrium analysis and gel filtration using polysaccharide or protein standards revealed a polydisperse preparation with molecular weights ranging from about 0.9 to 1.3 x 10(6). This suggests that in the native state epitectin exists as aggregates of three or four monomer units of 350-400 kDa. Epitectin was found to have significant affinity to hexyl-, octyl- or phenyl agarose indicating that hydrophobic interactions and possibly carbohydrate-carbohydrate interactions may be responsible for the self-association. Chemical and enzymic deglycosylation of [125I]-labeled urine epitectin and metabolically labeled H.Ep.2 epitectin resulted in extremely polydisperse products. The buoyant densities of epitectin purified from urine and H.Ep.2 cells were found to be 1.39-1.40 g ml(-1), suggesting that the total carbohydrate content of these preparations is not significantly different. The O-linked saccharides of epitectin were fractionated by HPLC and analyzed by permethylation and FAB-MS. The neutral saccharides from both sources contain three common structures, namely Gal1 --> 3GalNAc, GlcNAc1 --> 6 (Gal1 --> 3) GalNAc and Gal1 --> 4GlcNAc --> 6 (Gal1 --> 3)GalNAc. The sialic acid of urine epitectin consisted entirely of N-acetylneuraminic acid. The two sources of epitectin, in vitro labeled on sialic acid, were found to have the same sialyl oligosaccharides but in different proportions. Metabolic labeling and N-glycanase susceptibility experiments firmly established the presence of N-linked saccharides in epitectin as minor components. The remarkable similarities in the total carbohydrate content, the carbohydrate composition and structures of saccharides between epitectin from urine, a non-malignant source, and H.Ep.2 cells is surprising in view of the prevailing view that MUC1 glycoproteins of cancer cells are underglycosylated compared to those produced by non-malignant cells.


Assuntos
Antígenos Glicosídicos Associados a Tumores/urina , Aminoácidos/análise , Antígenos Glicosídicos Associados a Tumores/química , Sequência de Carboidratos , Centrifugação com Gradiente de Concentração , Cromatografia/métodos , Glicoconjugados/análise , Humanos , Neoplasias Laríngeas/imunologia , Masculino , Espectrometria de Massas , Dados de Sequência Molecular , Peso Molecular , Monossacarídeos/análise , Mucina-1/química , Células Tumorais Cultivadas
3.
J Immunol ; 158(10): 4721-8, 1997 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-9144485

RESUMO

Contact hypersensitivity (CHS) is a T cell-mediated response to hapten sensitization of the epidermis. Recent results from this laboratory indicated that hapten sensitization induces two populations of hapten-reactive T cells: CD8+ T cells producing IFN-gamma, which mediate the response, and CD4+ T cells producing IL-4 and IL-10, which function to limit the magnitude and the duration of the response. In the current report we first examined the hapten-presenting cell priming each of these T cell populations and then examined the influence of CD4+ T cell priming on the development of the CD8+ effector T cells. Isolation of hapten-presenting Langerhans cells from the lymph nodes of oxazolone-sensitized mice and transfer to naive mice resulted in the induction of both the regulatory CD4+ and the effector CD8+ T populations. Both CD4+ and CD8+ T cells expressing high levels of the activation determinants CD11a and CD44 appeared in the lymph nodes 3 days after hapten sensitization. The CD8+ T cells producing IFN-gamma and mediating CHS responses following transfer to naive mice were restricted to the high CD44-expressing population. In vitro activation of hapten-immune CD8+ T cells resulted in very low amounts (3 U/ml) of IL-2 production, whereas production of IL-2 by immune CD4+ T cells was approximately 70-fold higher (208 U/ml). Despite this discrepancy in IL-2 production and the coincidental priming of CD4+ and CD8+ T cells by hapten-presenting Langerhans cells during hapten sensitization, the numbers of CD8+/high CD44-expressing T cells in the lymph nodes were nearly identical when CD4+ T cells were present or absent during hapten priming. These results indicate that coincidental priming of CD4+ (and CD8+) T cells by LC does not augment CD8+ T cell development in CHS.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Dermatite de Contato/imunologia , Imunidade Celular , Animais , Epiderme/imunologia , Feminino , Haptenos , Receptores de Hialuronatos/metabolismo , Imunofenotipagem , Interferon gama/biossíntese , Interleucina-4/biossíntese , Células de Langerhans/imunologia , Cooperação Linfocítica , Depleção Linfocítica , Antígeno-1 Associado à Função Linfocitária/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Células Th1/imunologia , Células Th2/imunologia , Fatores de Tempo
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