摘要
目的探讨人胚胎纹状体区神经干细胞在体外的生物学特性。方法从16～20周人胚胎纹状体区分离培养神经干细胞，在体外进行传代、分化，应用免疫组织化学荧光染色等方法，对此区神经干细胞在体外增殖和分化等情况进行研究。结果纹状体区神经干细胞在体外原代培养扩增1月内分裂增殖速度快，在含有EGF和bFGF的培养基中生长最为良好，平均倍增时间为3～4d。分化培养后可以形成各种神经细胞，在原代培养后2周分化情况好，分化为神经元比例高，约占50％左右，在原代培养8周以后分化为神经元的比例下降，约占20％左右。结论人胚胎纹状体区的神经干细胞在体外有较强的自我更新和增殖能力，并表达了干细胞的原始特征，在体外传代过程中，增殖速度随着时间不断下降，其分化为各种神经细胞的能力也不同。培养基中的有丝分裂原对于神经干细胞的增殖和分裂的影响不同。神经球并非均质的，内部仅有部分细胞在分裂增殖。
Objective To investigate the biological characteristics of neural stem cells from the stfiatum of human embryos. Methods Neural stem cells were isolated from the strlatum of 16-20 weeks human embryos. These cells were cultured to proliferate and then differentiate without mitogens or inductive factors. At various time points the progeny of neural stem cells differentiation were analyzed. Using immunocytochemistry stainings, the biological characteristics of neural stem cells were examined. Results Neural stem cells in the striatum of 16-20 weeks human embryos proliferated rapidly in vitro within the first one month of culture at an average doubling time of 3-4 days. Upon mitogen withdrawal, the differentiation of neural stem cells to neurons exceeded 50%. After 8 weeks in culture,however, the proliferation speed of neural stem cells lowered significantly. The proportion of neurons induced by mitogen removal was under 20% .There were about 20% of cells within neurosphere continue to divide. Conclusion The proliferation and self-renewal ability of neural stem cells in the strlatum of 16-20 weeks human embryo is robust. In vitro, the rate of proliferation went down with time, and the ability of differentiation to multiple neural cells varied. The different mitogen factors in media have different effects on neural stem cell. Within neurospheres, neural stem cells are not homogenous, as only a portion of cells can divide.
出处
《解剖学报》
CAS
CSCD
北大核心
2006年第4期407-411,共5页
Acta Anatomica Sinica
基金
国家973计划基金资助项目(2001CB510104)
