BBB seminar: Uwe Himmelreich
In vivo monitoring of cell therapy – what contributions can imaging methods make in preclinical research?
Biomedical MRI Unit, Department of Imaging and Pathology, University of Leuven, Belgium
In vivo imaging methods like CT, optical imaging (BLI, FLI), MRI, ultrasound or PET are important tools in preclinical research. They provide information for longitudinal follow-up of disease progression and therapy on individual animals that are more difficult to be acquired by invasive histological approaches. In addition to monitoring anatomical and structural changes, molecular and cellular imaging techniques also provide metabolic and functional information. Non-invasive imaging of specific cell types has become a popular field of research over the last decades. This includes imaging of engrafted, therapeutic cells (stem cells, immune cells, pancreatic islets etc.) but also the targeting of intrinsic cells, in particular in oncology and immunology/infectious diseases. While pre-labeling of engrafted cells with contrast agents, tracers or reporter genes results in high specificity, imaging of intrinsic cells often relies on the targeting of receptors specifically expressed by a particular cell type. The most obvious challenge for the latter is the specificity of receptor expression for the targeted cell type. Other hurdles to overcome for in vivo cell imaging include: sensitivity; resolution; quantification; temporal profiles and adverse effects of contrast agents on the cell biology.
The advantage of pre-clinical imaging is that shortcomings of individual imaging methods can be overcome by combining several imaging modalities. This has resulted in robust, sensitive and potentially quantitative visualization of specific cell types in disease and therapy models. An overview of different approaches will be given; limitations and challenges will be outlined. Examples include stem cell imaging, tumor targeting and imaging in diabetes research.
CT, computed tomography; BLI and FLI, bioluminescence and fluorescence imaging; MRI, magnetic resonance imaging; PET, positron emission tomography
Chairperson: Hrvoje Miletic, Department of Biomedicine