Conferences2010 - '54th Biophysical Society Congress' in San Francisco (with contribution); 2010 - 'DPG' in Regensburg (with contribution); 2010 - '8th Int. Conference on the scientific and clinical applications of magnetic carriers' in Rostock (with contribution); 2011 - '55th Biophysical Society Congress' in Baltimore (with contribution); 2011 - '19th Annual Meeting & Exhibition ISMRM' in Montréal;
FellowshipsSiemens - TOPAZ; Siemens - leaders for tomorrow; Siemens - Talent Lounge; Siemens - Innovation Think Tank;;
CollaborationsFAU Erlangen, Emil Fischer Center - Animal Imaging; FAU Erlangen, Pattern Recognition Lab - Image Registration; FAu Erlangen, PI3 - Particle Characterization; UWA, School of Physics - Particle Characterization;
Current research / employment The main motivation for studying cell migration through connective tissue is trying to understand the process of cancer metastasis formation. The formation of metastasis is the reason why cancer is often a deadly disease. In this process single cancer cells spread from the tumor, invade and migrate through the tissue, transmigrate through the endothelium into a blood or lymph vessel where they get transported along until they adhere, again transmigrate out of the vessel and through the tissue until they form a secondary tumor at a distant site. Since the cancer cell invasion is a rate limiting step for metastasis formation, the understanding of the dynamics and the pathway will lead to novel treatment strategies. The research’s aim is to monitor non-invasively the dynamics of cell migration and invasion in animals over prolonged time periods using magnetic resonance imaging (MRI). The process of metastasis formation involves the migration and 3-D invasion of tumor cells from a primary tumor to distant sites. We propose that the dynamics of the migration and invasion process of magnetically labeled tumor cells can be monitored in animal models over prolonged time periods using magnetic resonance imaging (MRI). Human breast carcinoma cells (MB-MDA-231) were labeled with superparamagnetic Fe2O3 iron oxide nanoparticles (SPIO) coated with poly-L-lysine. The particles are readily taken up by cancer cells and stored in intracellular clusters. During cell division, the nanoparticle clusters are divided and split unevenly between daughter cells (mean partitioning fraction 0.85 to 0.15). Nanoparticles are non-toxic, are not degraded by the cell and remain stable for at least 3 weeks. In vitro collagen gel assays show no differences in contractile properties and invasion behavior of magnetically labeled vs. non-labeled tumor cells. MRI of cells suspended in agarose gave a detection limit of the spin-spin-relaxation-rate above the agar background of approximately 70 cells per 1 mm3. The minimal detection volume of tumor cells in agarose was 25 μl. Detection limit and minimal volume were verified by injecting labeled cancer cells in mice. Spin-spin-relaxation-weighted (T2-weighted) and susceptibility-weighted images show a rapid relaxation behavior and pronounced phase shifts in the vicinity of the injection area compared to control scans. These studies demonstrate the feasibility of the method for long-term observation of cancer cell migration in vivo with MRI.