Receptor-targeted optical imaging of tumors with near-infrared fluorescent ligands.
We report here the in vivo diagnostic use of a peptide-dye conjugate consisting of a cyanine dye and the somatostatin analog octreotate as a contrast agent for optical tumor imaging. When used in whole-body in vivo imaging of mouse xenografts, indotricarbocyanine-octreotate accumulated in tumor tissue. Tumor fluorescence rapidly increased and was more than threefold higher than that of normal tissue from 3 to 24 h after application. The targeting conjugate was also specifically internalized by primary human neuroendocrine tumor cells. This imaging approach, combining the specificity of ligand/receptor interaction with near-infrared fluorescence detection, may be applied in various other fields of cancer diagnosis.
Becker
A
A
Institut für Diagnostikforschung GmbH an der Freien Universität Berlin, 14050 Berlin, Germany.
Hessenius
C
C
Licha
K
K
Ebert
B
B
Sukowski
U
U
Semmler
W
W
Wiedenmann
B
B
Grötzinger
C
C
D000818:Animals; D002232:Carbocyanines / Q000378:metabolism* / Q000493:pharmacokinetics*; D002478:Cells, Cultured; D003952:Diagnostic Imaging / Q000379:methods*; D004705:Endocytosis; D005434:Flow Cytometry / Q000379:methods; D005456:Fluorescent Dyes / Q000378:metabolism*; D006801:Humans; D008024:Ligands; D051379:Mice; D008819:Mice, Nude; D018613:Microscopy, Confocal / Q000379:methods; D008856:Microscopy, Fluorescence / Q000379:methods*; D009368:Neoplasm Transplantation; D009369:Neoplasms / Q000473:pathology*; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D051381:Rats; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D013997:Time Factors; D014407:Tumor Cells, Cultured
D002232:Carbocyanines; D005456:Fluorescent Dyes; D008024:Ligands