ES细胞来源的神经前体细胞移植Aβ损伤大鼠海马后的分化及对学习记忆的改善

Differentiation of neural precursor cells derived from mouse embryonic stem cells after transplantation into Aβ injured rat hippocampus and the improvement in memory

目的观察来源于小鼠胚胎干细胞的神经前体细胞移植Aβ海马损伤大鼠后的存活、分化以及细胞移植对模型大鼠的治疗作用。方法采用改良的无血清方法将表达绿色荧光的小鼠胚胎干细胞定向诱导为神经前体细胞,移植至单侧海马注射Aβ1-40损伤模型大鼠注射处;免疫荧光双染观察移植细胞的存活、分化。结果胚胎体在改良的N2选择性培养基生长5d后,90%以上的小鼠胚胎干细胞分化为nestin阳性神经前体细胞。移植到模型大鼠海马后神经前体细胞存活良好,EGFP荧光显示移植细胞呈集落生长,Cy3荧光显示大部分细胞分化为GFAP阳性细胞,移植区周围可见一定数量NF200阳性细胞,其中部分发出类似神经元的长突起。行为学结果显示移植大鼠记忆能力较对照组明显改善。结论胚胎干细胞来源的神经前体细胞移植Aβ1-40损伤模型大鼠海马后能有效存活,大部分移植细胞分化为胶质细胞,小部分分化为神经元,细胞移植能改善模型大鼠学习记忆功能障碍。

Objective To observe the survival, differentiation and the therapeutic effect of neural precursor cells （NPCs） derived from mouse embryonic stem cells （ESc） after transplanted into Aβ-injured rat hippocampus. Methods NPCs were generated from mouse ESc expressing EGFP with modified serum-free methods and then transplanted into the hippocampus of Alzheimer＇ s disease （AD） rat model developed by Aβ1-40 microinjection. The survival and differentiation of transplanted NPCs were observed with immunofluorescence methods. The learning and memory ability of AD rats were investigated. Results About 90% of mouse ESc were differentiated into nestin-positive NPCs 5 d after the induction with modified N2 serum-free medium. The grafted NPCs in the hippocampus of AD rats showed good survival rate and grew into GFP positive colonies, and mostly differentiated into GFAP-positive glia and some into NF200-positive neurons with long evection as to the neuron. The ability in learning and memory of AD rats was much improved after NPCs transplantation compared with that of control group. Conclusion The NPCs derived from ESc are survived and mostly differentiated into the glial cells and a few into neurons after grafted into the hippocampus of AD rats, and show therapeutic effect on AD as improved learning and memory abilities.