Abstract 9045: MRI of Autotransplantation of Bone Marrow-Derived Stem-Progenitor Cells: Toward Cell-Based Repair of Injured Arteries
Bone marrow (BM) derived stem-progenitor cells (SPCs) are capable of migrating to injured arteries for repairing and stabilizing vulnerable atherosclerotic plaques. The aim of this study was to validate the feasibility of using clinical MRI to monitor auto-transplanted BM-SPC migration to the injured arteries of near-human-sized pigs. For in vitro study, BM cells were extracted from 6 pigs, and then purified and labeled with ferumoxides (a MR T2 contrast agent) and/or PKH26 (a cell membrane dye). Cell viability, proliferation, and labeling efficacy were determined by Trypan blue exclusion, MTS assay, and cell counting, respectively. For in vivo study, thirteen pigs with balloon-injured iliofemoral arteries were divided into 3 groups with autotransplantation of (1) ferumoxides/PKH26-co-labeled BM cells (n=5); (2) ferumoxides-only labeled BM cells (n=5); (3) non—labeled BM cells or no cell transplantation (n=3). Three weeks later, 3.0T MRI was performed to detect ferumoxides-created signal voids. Then, artery segments were harvested, cryosectioned, and stained with (a) H & E to grade the injured arteries; (b) Prussian blue stain to detect ferumoxides+ cells; (c) immunochemical anti-dextran stain to detect ferumoxides shell; and (d) fluorescent microscopy to detect PKH26+ cells. Trypan blue exclusion showed the viabilities of labeled cells at 95–98%. Proliferation efficiency was confirmed no significant difference among labeled and control cell groups. The cell labeling efficacy was about 90% for ferumoxides and 100% for PKH26. MRI revealed signal voids along the iliofemoral artery walls, which were confirmed by subsequent histology. In Conclusions, this study demonstrates the capability of using clinical MRI to monitor autotransplantation of BM cells that migrate to the injured arteries for potential repair in near-human-sized animals, which may open new avenues to effectively manage atherosclerotic cardiovascular disease.
- © 2010 by American Heart Association, Inc.