Registro completo |
Provedor de dados: |
BJMBR
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País: |
Brazil
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Título: |
Evaluation of an anti-carcinoembryonic monoclonal antibody suitable for immunoscintigraphy
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Autores: |
Moraes,D.W.
Lima,E.N.P.
Prado,I.B.
Carneiro,C.R.W.
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Data: |
1999-08-01
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Ano: |
1999
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Palavras-chave: |
Monoclonal antibody
Carcinoembryonic antigen
Colorectal carcinoma
Immunoscintigraphy
Technetium-99m
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Resumo: |
An anti-carcinoembryonic antigen (CEA) monoclonal antibody (mAb 6D1.1) was evaluated in vitro and in vivo to determine its suitability as a tracer for immunoscintigraphy of colorectal carcinomas. Determination of mAb affinity for CEA showed a constant of association of 0.63 ± 0.11 x 109 M-1. Binding of technetium-99m (99mTc)-6D1.1, labeled by a direct method, to human cultured lineages was highly specific. Binding to only CEA-positive LS-174T cells resulted in a saturable curve inhibited by pre-incubation with unlabeled mAb. No binding at all was observed for the human lineages MeWo (melanoma) or ZR75-30 (breast carcinoma), neither of them expressing CEA cells. Intravenous injection of 99mTc-6D1.1 into nude mice xenografted with human LS-174T tumors resulted in planar images of excellent quality. Localization of an irrelevant mAb labeled with either 99mTc or iodine-125 was never observed in tumor masses. Biodistribution studies on excised tumoral tissue showed retention of 28.48% of the injected dose per gram of LS-174T tumor. The tumor-to-blood ratio was 3.46. The same analysis performed on the other three human xenografted tumors studied demonstrated that only the CEA-producing HT-29 (colorectal adenocarcinoma) retained 99mTc-6D1.1 while the other two (ZR75-30 and MeWo) did not. These data demonstrate that this mAb is an adequate tool for targeting CEA-expressing tumors in experimental models.
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Tipo: |
Info:eu-repo/semantics/article
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Idioma: |
Inglês
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Identificador: |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000800006
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Editor: |
Associação Brasileira de Divulgação Científica
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Relação: |
10.1590/S0100-879X1999000800006
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Formato: |
text/html
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Fonte: |
Brazilian Journal of Medical and Biological Research v.32 n.8 1999
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Direitos: |
info:eu-repo/semantics/openAccess
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