| Title | Collagen-based matrices improve the delivery of transplanted circulating progenitor cells: development and demonstration by ex vivo radionuclide cell labeling and in vivo tracking with positron-emission tomography. | | Author(s) | Zhang Y, Thorn S, DaSilva JN, Lamoureux M, DeKemp RA, Beanlands RS, Ruel M, Suuronen EJ | | Institution | Division of Cardiac Surgery, University of Ottawa, Ottawa, Canada. | | Source | Circ Cardiovasc Imaging 2008 Nov; 1(3):197-204. | | Abstract | BACKGROUND: Collagen delivery matrices have been reported to improve the results of cell therapy, but knowledge of their mechanisms of action is limited. To evaluate whether a collagen matrix improves early engraftment posttransplantation, 2-[(18)F]fluoro-2-deoxy-d-glucose ((18)F-FDG) was used to label transplanted circulating progenitor cells (CPCs) and track them in vivo with positron-emission tomography.
METHODS AND RESULTS: Efficiency of (18)F-FDG cell labeling was CPC-concentration dependent (r=0.61, P<0.001) but not (18)F-FDG-dose dependent. Labeled human CPCs (2x10(6)) were injected with or without a collagen-based matrix in the ischemic hind limb of rats (n=12 per group) 2 weeks after femoral artery ligation. Imaging of labeled cells, acquired by small animal positron-emission tomography at 150 minutes postinjection, revealed greater CPC retention in the ischemic hind limb and less nonspecific leakage to other tissues (retention ratio, 0.44+/-0.08) when CPCs were delivered within the matrix, compared with cells injected alone (0.22+/-0.13, P=0.040) and with (18)F-FDG injected with or without the matrix (0.10+/-0.05 and 0.11+/-0.05, respectively, P<0.005). Tissue radionuclide biodistribution was performed after completion of positron-emission tomography imaging. When (18)F-FDG-labeled cells were injected with the collagen matrix, accumulation was significantly increased (by 69.6%, P=0.021) in the target ischemic hind limb muscle and significantly reduced (by 14.8% to 31.4%, P<0.05) in nonspecific tissues, compared with cells injected alone. Histology confirmed the increased retention in target tissue associated with the matrix.
CONCLUSIONS: Early posttransplantation, a collagen matrix enhances progenitor cell retention and limits distribution to nonspecific tissues, as measured by the use of (18)F-FDG labeled cells and positron-emission tomography imaging and confirmed by biodistribution and histology. | | Language | eng | | Pub Type(s) | Journal Article
Research Support, Non-U.S. Gov't
| | PubMed ID | 19808543 |
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