In vivo CEST MR imaging of U87 mice brain tumor angiogenesis using targeted LipoCEST contrast agent at 7 T.
Magn Reson Med
; 69(1): 179-87, 2013 Jan.
Article
en En
| MEDLINE
| ID: mdl-22378016
LipoCEST are liposome-encapsulating paramagnetic contrast agents (CA) based on chemical exchange saturation transfer with applications in biomolecular MRI. Their attractive features include biocompatibility, subnanomolar sensitivity, and amenability to functionalization for targeting biomarkers. We demonstrate MR imaging using a targeted lipoCEST, injected intravenously. A lipoCEST carrying Tm(III)-complexes was conjugated to RGD tripeptide (RGD-lipoCEST), to target integrin α(ν)ß(3) receptors involved in tumor angiogenesis and was compared with an unconjugated lipoCEST. Brain tumors were induced in athymic nude mice by intracerebral injection of U87MG cells and were imaged at 7 T after intravenous injection of either of the two contrast agents (n = 12 for each group). Chemical exchange saturation transfer-MSME sequence was applied over 2 h with an average acquisition time interval of 13.5 min. The chemical exchange saturation transfer signal was â¼1% in the tumor and controlateral regions, and decreased to â¼0.3% after 2 h; while RGD-lipoCEST signal was â¼1.4% in the tumor region and persisted for up to 2 h. Immunohistochemical staining revealed a persistent colocalization of RGD-lipoCEST with α(ν)ß(3) receptors in the tumor region. These results constitute an encouraging step toward in vivo MRI imaging of tumor angiogenesis using intravenously injected lipoCEST.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Neoplasias Encefálicas
/
Imagen por Resonancia Magnética
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Medios de Contraste
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Liposomas
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Neovascularización Patológica
Límite:
Animals
Idioma:
En
Revista:
Magn Reson Med
Asunto de la revista:
DIAGNOSTICO POR IMAGEM
Año:
2013
Tipo del documento:
Article
País de afiliación:
Francia
Pais de publicación:
Estados Unidos