Parts | Days | Selection | Search | Downloads | Help
BP: Fachverband Biologische Physik
BP 32: Posters: Physics of Cells
BP 32.43: Poster
Thursday, March 25, 2010, 17:15–20:00, Poster B1
Magnetic Resonance Imaging (MRI) of tumor cell migration in animals — •Christian Weis1, Ben Fabry1, and Andreas Hess2 — 1Biophysics Group, FAU Erlangen-Nürnberg — 2Lehrstuhl für Pharmakologie und Toxikologie, FAU Erlangen-Nürnberg
The process of metastasis formation involves the migration and 3-D invasion of tumor cells from a primary tumor to distant sites. Our aim was to monitor the dynamics of cell migration and invasion in animals over prolonged time periods using MRI. Human breast carcinoma cells were labeled with superparamagnetic γFe2O3 iron oxide nanoparticles. Particles were stabilized and biofunctionalized with poly-l-lysine. Approximately 10,000 cells were incubated with 1 ug of particles for 24 h. Particles are readily taken up by cancer cells and stored in intracellular clusters. During cell division, the nanoparticle clusters are divided and split between daughter cells. Nanoparticles remain stable for at least 3 weeks. In-vitro collagen gel assays show that there is no difference between the spreading or invasion behavior of tumor cells with and without nanoparticles. MRI imaging (conventional multi-spin sequences with a repetition time of 1000 ms and 8 echo times between 11 and 165 ms) of cells suspended in 2% agar gave a detection limit of the R2 relaxation rate of 20 uM Fe2O3, equivalent to 70 cells/mm2. The minimal detection volume of tumor cells in agar was 25 ul. Detection limit and minimal volume were verified by injecting labeled cancer cells in dead mice. To achieve high sensitivity in mice, however, a slice thickness of less than 250 um was necessary, which leads to whole-body scans with physiologically unacceptable duration (> 4h).