1.Experimental Study On Culturing, Identification And Differentiation Of Neural Stem Cells From Newborn Rat 2.Experimental Study On Magnetic Resonance Imaging Tracking Of Superparamagnetic Iron Oxides Labeled Neural Stem Cells Migration In Vivo

Objective:To establish the methods of culturing neural stem cells (NSCs) from newborn rat brain,observe the characteristics of multipotentialty and induced differentiation and to make the bases for further study on making magnetic labeled NSCs. Methods:Using serum free culture medium and mitogen factors,NSCs of newborn rat were isolated and cultured. Technique of subculture and single-cell clone culture was used to confirm the character of self-renewing. Ability of multi-directional differentiation and specific antigen, Nestin, were detected by indirect- immunofluorescence and immunocytochemistry . BrdU was used to show cell stage in division. Effect of combination of EGF, bFGF on proliferation of rat NSCs were evaluated by clone forming and cytometry. Results:The cultured NSCs showed multipotential of differentiate into neurons and glial cells and the ability of self-renewing. Cells expressed Nestin. The property of NSCs was stable after subculture. Combination of EGF and bFGF stimulated cell proliferation than used single. Conclusions:The cultured NSCs express Nestin and have the ability of self-renewing and multi-directional differentiation. Combination of EGF and bFGF could promote the proliferation of rat NSCs. Objetive:To track of superparamgnetic iron oxides (SPIOs) labeled neural stem cells (NSCs) migration into rat middle cerebral artery occlusion (MCAO) in vivo by magnetic resonance imaging(MRI). Methods:Resovist/Feridex (two kinds of SPIOs) and Poly-D-lysine were added into the medium to be co-cultured to make magnetic labeled NSCs.With immunocytochemistry,transmission electron microscopy (TEM) and Prussian blue staining,we researched the growth,differentiation and other biology characteristics. We migrated Feridex-labeled NSCs into the lateral ventricle of rat MCAO to monitor in vivo. And use histopathology detection to confirm the result of MRI. Results: When NSCs incubated with Resovist/Feridex, we can see the iron particles are in intracellular (non-nucleus) and also existed in dauhgter clones. With the concentration of Resovist/Feridex increased (2.8-11.2μg/ml), they have no obvious difference to the growth and differentiation of NSCs( P>0.05); When they exceeded 22.4μg/ml,there have obvious difference to the growth and differentiation of NSCs (P<0.05);In the same concentration, Resovist had no obvious difference compared to Feridex (P>0.05). Feridex-labeled NSCs are in low signal in MRI. And with time past, Magnetic labeled NSCs were migrating into occlusion area. Conclusion: We successfully labeled NSCs with Feridex to be magnetic labeled NSCs. And we were also tracking and observingmagnetic labeled NSCs migration towards ischemic area in vivo with MRI.