ABSTRACT
BACKGROUND:Superparamagnetic iron oxide (SPIO) labeling can trace the migration of stem cells in vivo, and the fluorescent DiI dye is suitable for marking and tracing cells because of its less influence on cellviability, proliferation and differentiation. OBJECTIVE:To observe the effect and safety of SPIO and fluorescent DiI dye to double label bone marrow mesenchymal stem cells. METHODS:The bilateral lower limbs of rats were isolated sterilely. Bone marrow was obtained by rinsing using low-glucose DMEM. Bone marrow mesenchymal stem cells were isolated by the whole bone marrow adherence method and purified by differential attachment method. Purified cells were dual-labeled with SPIO particle and fluorescent DiI dye. RESULTS AND CONCLUSION:Bone marrow mesenchymal stem cells could be separated at 8-10 days after primary culture and the subculturing cycle was 3-4 days. Rat bone marrow mesenchymal stem cells could be effectively labeled with SPIO-DiI and the labeling efficiency was almost 100%. Blue irons contained in intracytoplasmatic vesicles could be observed clearly with Prussian blue staining, and the fluorescence microscopy showed red fluorescence at cytoplasm. Survival and apoptosis percentages obtained by MTT analysis were similar among labeled and unlabeled bone marrow mesenchymal stem cells that were both about 95%.These findings indicate that the rat bone marrow mesenchymal stem cells could be efficiently labeled with SPIO-DiI to construct a nano-bioprobe, without significant changes in morphology, viability and proliferation.