title: Synthesis and biological investigations of a ZnPc-antiCEA bioconjugate for imaging of colorectal cancer.
abstract: Two zinc(II) phthalocyanines (ZnPcs) were conjugated with a monoclonal antibody (MAb) directed against carcinoembryonic antigen (CEA), using anin situactivated carboxylic acid on the ZnPcs. The bioconjugate with the highest ZnPc/MAb ratio of 3 was investigatedin vitrofor its ability to target and fluorescently label human colorectal HT-29 cells. The ZnPc-CEA MAb2was observed to efficiently target HT-29 cells, about 37 times more than unconjugated ZnPc. Furthermore, in the presence of a 4-fold excess of unlabelled anti-CEA antibody, the fluorescence signal of2was reduced by ~90% showing that the targeting is CEA-mediated. These studies further confirm the high specificity of Pc-antibody conjugates for antigens over-expressed on tumor cells and warrant further investigations of these immunoconjugates and their derivatives for imaging of colorectal cancer.
authors.affiliation: Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA.
authors.forename: Inder
authors.initials: I
authors.lastname: Sehgal
authors.affiliation: Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA.
authors.forename: Hairong
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA.
authors.forename: Benson
authors.initials: B
authors.lastname: Ongarora
authors.affiliation: Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Devillier
authors.affiliation: Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA.
authors.forename: M Graça H
authors.initials: MG
authors.lastname: Vicente
keywords: antibody; carcinoembryonic antigen; colorectal cancer; fluorescence; phthalocyanine