title: Non-Invasive In Vivo Imaging and Quantification of Tumor Growth and Metastasis in Rats Using Cells Expressing Far-Red Fluorescence Protein.
abstract: Non-invasive in vivo imaging is emerging as an important tool for basic and preclinical research. Near-infrared (NIR) fluorescence dyes and probes have been used for non-invasive optical imaging since in the NIR region absorption and auto fluorescence by body tissue is low, thus permitting for greater penetration depths and high signal to noise ratio. Currently, cell tracking systems rely on labeling cells prior to injection or administering probes targeting the cell population of choice right before imaging. These approaches do not enable imaging of tumor growth, as the cell label is diluted during cell division. In this study we have developed cell lines stably expressing the far-red fluorescence protein E2-Crimson, thus enabling continuous detection and quantification of tumor growth. In a xenograft rat model, we show that E2-Crimson expressing cells can be detected over a 5 week period using optical imaging. Fluorescence intensities correlated with tumor volume and weight and allowed for a reliable and robust quantification of the entire tumor compartment. Using a novel injection regime, the seeding of MDA-MB-231 breast cancer cells in the lungs in a rat model was established and verified.
authors.affiliation: Institute for Macromolecular Chemistry, University of Freiburg, 79104, Freiburg, Germany; BIOSS-Centre for Biological Signalling Studies, University of Freiburg, 79104, Freiburg, Germany.
authors.forename: Jon
authors.initials: J
authors.lastname: Christensen
authors.affiliation: Institute for Macromolecular Chemistry, University of Freiburg, 79104, Freiburg, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Vonwil
authors.affiliation: Institute for Macromolecular Chemistry, University of Freiburg, 79104, Freiburg, Germany; BIOSS-Centre for Biological Signalling Studies, University of Freiburg, 79104, Freiburg, Germany.
authors.forename: V Prasad
authors.initials: VP
authors.lastname: Shastri
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology / Q000648:ultrastructure*; D045744:Cell Line, Tumor; D005260:Female; D005456:Fluorescent Dyes; D015870:Gene Expression; D006801:Humans; D008164:Luminescent Proteins / Q000235:genetics* / Q000378:metabolism; D008175:Lung Neoplasms / Q000235:genetics / Q000473:pathology / Q000648:ultrastructure*; D008207:Lymphatic Metastasis; D009368:Neoplasm Transplantation; D061848:Optical Imaging / Q000295:instrumentation / Q000379:methods*; D051381:Rats; D011923:Rats, Nude; D059629:Signal-To-Noise Ratio; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation / Q000379:methods*; D019076:Transgenes; D014183:Transplantation, Heterologous; D047368:Tumor Burden; D023041:Xenograft Model Antitumor Assays; D000097573:Red Fluorescent Protein
chemical_list: D005456:Fluorescent Dyes; D008164:Luminescent Proteins; D000097573:Red Fluorescent Protein