22-07-08(15:36:58)
Authors:
Himmelreich U
Crabbe A
Vandeputte C
Dresselaers T
van Laere K
Verfaillie C
Institutions:
Biomedical NMR Unit, Molecular Small Animal Imaging Center and Stem Cell Institute Leuven, Faculty of Medicine, Katholieke Universiteit Leuven
Title of abstract : Multimodal stem cell imaging.
Abstract text:
MRI is one of the most powerful tools for high-resolution, non-invasive imaging. Apart from monitoring anatomical and functional changes, the location and migration of cells can be followed by MRI. Current limitations of cell imaging by using MRI can be overcome by combining it with other imaging modalities like bioluminescence imaging or positron emission tomography.
It was the aim of this study to optimize methodological aspects of cell labelling strategies for robust, sensitive and potentially quantitative visualisation of multipotent adult progenitor, mesenchymal and embryonic stem cells. The sensitivity, stability, toxicity and adverse effects on the cell biology by the labelling procedure was studied for ultrasmall, small and micron-sized iron oxide particles. In vivo imaging was performed in control animals and stroke animal models.
Although, the actual labelling procedure can be straight forward, there are several issues that require careful consideration for (stem) cell labelling and their in vivo applications. Among these issues are:
(1) Generation of highly sensitive contrast for the visualization of small cell numbers
(2) (Semi)quantification of cell numbers in vitro and in vivo
(3) Generation of unambiguous contrast that distinguishes cells from other sources of hypo- or hyperintensity in MR images
(4) Stable binding or incorporation to avoid contrast agent leakage or transfer to cells of the host
(5) Prevention of toxicity or harmful alterations of cellular processes by the contrast agent
(6) Minimal influence on the physiological behavior of the cells in the host
(7) Generation of contrast even after continued cell proliferation.
