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1.
J Immunother ; 30(1): 29-39, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17198081

RESUMO

A general hindrance to progress in adoptive cellular therapy is the lack of detailed knowledge of the fate of transferred cells in the body of the recipient. In this study, we present a novel technique for tracking of 124I-labeled cells in situ, which combines the high spatial resolution of magnetic resonance imaging with the high sensitivity and spatial accuracy of positron emission tomography. We have used this technique, together with determination of tissue radioactivity, flow cytometry, and microscopy, to characterize and quantitate the specific accumulation of transferred CD8+ T cells in tumor tissue in a mouse model. Transgenic CD8+ T cells, specific for the ovalbumin peptide SIINFEKL, were adoptively transferred to recipients carrying a subcutaneous tumor of the ovalbumin-expressing malignant melanoma cell line B16-OVA. The number of SIINFEKL-specific CD8+ cells in the tumor tissue was determined by flow cytometry each day for 8 consecutive days after adoptive transfer. From low levels 1 day after injection, their number gradually increased until day 5 when an average of 3.3x10(6) SIINFEKL-specific cells per gram tumor tissue was found. By applying the combined positron emission tomography/magnetic resonance imaging technique we were able to determine the position of the transferred, 124I-labeled SIINFEKL-specific T cells in 3 dimensions in recipient mice, and could demonstrate a highly significant accumulation of the 124I label in and around the subcutaneous B16-OVA tumors compared with normal tissue. Accumulation of 124I was significantly higher in B16-OVA than in B16 tumors not expressing the OVA antigen.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Imunoterapia Adotiva/métodos , Melanoma Experimental/imunologia , Receptores de Retorno de Linfócitos/imunologia , Animais , Proteínas do Ovo/imunologia , Feminino , Radioisótopos do Iodo , Imageamento por Ressonância Magnética , Masculino , Melanoma Experimental/diagnóstico por imagem , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Ovalbumina/imunologia , Fragmentos de Peptídeos , Tomografia por Emissão de Pósitrons
2.
Cancer Immunol Immunother ; 53(6): 560-6, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-14985861

RESUMO

PURPOSE: We wanted to study whether an allogeneic melanoma lysate would be a feasible stimulatory antigen source for detection of a peripheral CD4+ T-cell immune response in patients with medically untreated malignant melanoma. The lysate was produced from a melanoma cell line (FM3.29) which expresses high amounts of melanoma antigens. METHODS: Fresh peripheral blood was incubated with and without lysate for 6 h in the presence of anti-CD28/anti-CD49d MoAb (for costimulation). After flow cytometric estimation of the frequency of CD69+/IFN-gamma+ cells in the CD4+ population, the response to lysate was calculated as the difference between the number of activated IFN-gamma-producing CD4+ cells in the lysate-stimulated and the nonstimulated sample. RESULTS: An immune response to lysate was observed in blood samples from 11 of 15 patients (73%) with metastatic melanoma. A weak response was found in 1 of 4 patients radically operated for localized disease, whereas no responders were seen among 7 healthy donors. The fraction of circulating lysate-activated T cells ranged from 0.0037% to 0.080% of the CD4+ population. A negative result of the assay was found occasionally, especially in donors with high background levels of spontaneous IFN-gamma production, indicating an inhibitory effect of the lysate. CONCLUSIONS: This method for detection of a peripheral T-cell immune response in melanoma patients has several advantages for clinical use. The tumor lysate preparations may contain large numbers of stimulating antigens (known, as well as unknown) and are easily prepared and handled. Potentially, the assay might be useful as a diagnostic tool, a marker of residual or recurrent disease, a prognostic factor, or a predictor or monitor of the effect of antineoplastic therapy including immune-modulating therapy.


Assuntos
Antígenos de Neoplasias/imunologia , Linfócitos T CD4-Positivos/imunologia , Melanoma/sangue , Melanoma/imunologia , Adulto , Idoso , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Estudos de Casos e Controles , Diagnóstico Diferencial , Feminino , Citometria de Fluxo , Humanos , Interferon gama/metabolismo , Lectinas Tipo C , Masculino , Melanoma/secundário , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/patologia , Prognóstico , Neoplasias Cutâneas/sangue , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/secundário
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