Page 13 - Cellular Imaging in Regenerative Medicine, Cancer and Osteoarthritis

activated macrophages during inflammatory disease in a mouse model for osteoarthritis (OA). Different phenotypes of macrophages are present overtime during inflammatory disease processes such as in OA. Knowing which phenotype is present at a certain moment can help determining the stage of disease, but also give directions how to interfere in the disease development. So, for cellular imaging in regenerative medicine, cancer and inflammatory processes such as in osteoarthritis it is important to label the cells involved in the disease, so they can be non-invasively detected with an imaging device. This to be able to stage the disease and to be able to interfere in the disease development.
Imaging cells in regenerative medicine
Regenerative medicine deals with the restoration of damaged or ageing tissues. Stem cells have infinite cell division potential and can differentiate into other types of cells and have an important role in regenerative medicine research. Earlier, evaluations of the effectiveness of regenerative approaches were limited by the inability to monitor response to treatment over time, but nowadays we are able to incorporate a label into the cells by which the transplanted cells can be distinguished from their surrounding using imaging technologies (8-10). This way it is possible to determine their fate as well as their functional capabilities and the biological role they fulfill (11). We searched for the best iron labelling protocol for cells in vitro and in vivo, and we tried to quantify the iron labelled cells.
Cancer cell imaging for diagnosis and therapy
In preclinical tumour imaging studies nuclear imaging markers can be applied and are widely being used (12). Glucose metabolism is a key cellular function in cells, which is high in tumour cells, and can be imaged with a radioactive glucose derivative: 18F[F]-FDG (13, 14). Receptors on or in tumour cells can be imaged with the use of e.g. peptide receptor radionuclide imaging. In the paragraph on targeted radiolabelled peptides, their structure and receptor- mediated uptake mechanisms are described.
For the last 20 years peptide receptor radionuclide therapy (PRRT) has been used to treat patients suffering from neuroendocrine tumours (NETs). These NETs are rare cancers, they are often already metastasized at time of diagnosis
Introduction
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