Abstract: Objective: To explore the feasibility of protocols using Feridex and transfection agents for in vitro magnetic labeling of bone marrow stromal cells (BMSCs). Methods: Under the sterile condition, the crab-eating Macaque bone marrow stromal cells were harvested by means of density gradient centrifugation following a bone puncture. Feridex-poly-l-lysine (FE-PLL) complexes were used to magnetically label BMSCs. The efficiency and cellular viability of FE-PLL labeled BMSCs were evaluated by Prussian blue staining, electron microscopy, and trypan blue dye exclusion test. The proliferation and differentiation ability of FE-PLL labeling BMSCs were also investigated by Inverted phase contrast microscope and immunocytochemistry. Results: BMSCs could be effectively labeled and labeling efficiency were around 99%. Numerous blue stained fine particles and numerous vesicles filled with the electron-dense magnetic iron particles could be found in the cytoplasm of FE-PLL labeled BMSCs under optical microscopy and transmission electron microscopy respectively. Cell viability, proliferation and differentiation ability of labeled cell were not affected by endosomal incorporation of Feridex nanoparticles. Conclusion: The Feridex might be used to label BMSCs of crab-eating Macaque.

Key words: bone marrow stromal cells, neural stem cells, Feridex, superparamagnetie iron oxide