中文摘要：

家畜精原干细胞操作的核心技术是精原干细胞（spermatogonial stem cells,SSCs）的长期培养。至今家畜精原干细胞的长期培养方法还没有完善。其中的一个原因是缺乏简便有效的家畜精原干细胞生物活性鉴定手段。该研究的目的是建立一种牛精原干细胞生理潜能的体外分析方法,用于体外培养的牛精原干细胞的生物活性鉴定。首先培养牛精原干细胞,进而用干细胞因子（stem cell factor,SCF）对体外长期培养的牛精原干细胞进行诱导分化。在诱导分化过程中对细胞进行显微观察,并且用免疫荧光染色法鉴定分化的细胞。观察结果显示,经过诱导培养8 d后,牛精原干细胞形态发生了明显改变;细胞的运动行为显示出精母细胞特有的特征。免疫荧光染色结果显示,分化的细胞表达精母细胞的标记基因Scp3。上述结果例证了体外培养的牛精原干细胞具有分化为精母细胞的潜能。该研究建立了牛SSCs体外诱导分化的分析方法,用于鉴定体外培养的牛SSCs的生理潜能。但是体外诱导培养条件不能满足牛SSCs减数分裂的全部要求,导致出现一些不完全符合精母细胞特征的现象。诱导分化培养液尚需改进。

英文摘要：

Long-term culture of spermatogonial stem cells（SSCs） in vitro is the core technique of the spermatogonial stem cell manipulation in livestock.However,the method for long-term culture of livestock SSCs has not yet been established so far.One of the reasons is lack of a simple and effective approach for analysis of biological activity of the livestock SSCs.The purpose of this study was to establish a method for identification of the bovine SSCs（b SSCs） biological activity in vitro.Firstly,bSSCs were cultured.Then,bSSCs were induced with stem cell factor（SCF） for differentiation in vitro.During the induction,the cells were observed with microscope,and the differentiated cells were identified by immunofl uorescence staining.The results from observitions showed that the morphology of the bSSCs was changed obviously after induction culture for 8 d;and the cell motion behavior revealed specific characteristic of spermatocytes.The results from immunofl uorescence staining showed that the differentiated cells expressed Scp3,a marker gene of spermatocytes.The results above illustrate that the bSSCs cultured in vitro possess the potential for differentiation into spermatocytes.In this study,the analysis method for inducing differentiation of the bSSCs has been established,and it can be applied for identification of physiological potential of the b SSCs cultured in vitro.However,culture conditions of inducing differentiation in vitro can＇t meet all of the requirements for b SSC meiosis,resulting in some phenomena not fitting completely with the characteristics of spermatocyte.The culture medium of inducing differentiation still needs improvement.