In Vivo MRI Tracking of XXXX -Wrapped Superparamagnetic @entity1933 Nanoparticle-Labeled BMSCs for Cartilage Repair: A Minipig Model.

@entity12279 @entity21044 @entity1933 @entity8681 @entity2654
OBJECTIVE: To evaluate the feasibility of tracking @entity12279 ( @entity8681 )-wrapped superparamagnetic @entity1933 (SPIO) nanoparticle-labeled, bone marrow-derived mesenchymal stem cells (BMSCs) by in vivo magnetic resonance imaging (MRI) in articular cartilage repair in a minipig model. METHODS: Eighteen Guizhou minipigs were randomly divided into three groups (groups A, B, and C). In group A, @entity8681 -wrapped SPIO nanoparticle ( @entity8681 /SPIO) and green fluorescent protein (GFP) colabeled, autologous BMSCs seeded in type II collagen gel were transplanted into the articular cartilage defects of the minipig model. In group B, GFP-labeled, autologous BMSCs seeded in type II collagen gel were transplanted. In group C, no treatment was applied for cartilage defects. All minipigs underwent clinical 3.0-T MR imaging at 4, 8, 12, and 24 weeks postsurgery. The findings were compared histologically. RESULTS: Prussian staining and transmission electron microscope showed that BMSCs were efficiently labeled by @entity8681 /SPIO. Cell viability, proliferation, and differentiation were comparable between labeled and unlabeled cells. MRI @entity21044 WI sequence revealed that marked @entity2654 representing the transplanted labeled BMSCs could be observed for at least 24 weeks. Histochemical staining confirmed the presence of Prussian blue-positive cells and GFP-positive cells at the @entity2654 . At 24 weeks postsurgery, both MR signals and histologic staining of minipigs in groups A and B at the cartilage defect were close to the normal cartilage. CONCLUSIONS: 3.0-T MRI in vivo tracking of @entity8681 /SPIO-labeled BMSCs seeded in type II collagen gel on cartilage repair following transplantation is feasible in minipigs.
