骨髓间充质干细胞的分离培养及在精原细胞培养条件下生物学特征的观察

目的体外分离、培养、纯化小鼠骨髓间充质干细胞(MSCs),并观察MSCs在精原细胞培养条件下的生物学特征,为体内诱导MSCs分化为精原细胞奠定基础。方法①分离5～6周龄的BALB/c小鼠胫骨、股骨,冲出骨髓,以Percoll密度梯度离心法和贴壁法相结合的方法分离、培养、纯化MSCs;②通过动态观察、苏木精伊红(HE)染色、透射电镜观察、免疫组化检测细胞表面标记等鉴定MSCs;③用ELISA法检测MSCs培养上清中白细胞介素6(IL6)、IL8、粒细胞集落刺激因子(G CSF)、干细胞因子(SCF)等细胞因子的相对含量,与相应对照组比较;④取第3代MSCs,分组进行诱导培养观察,对照组用基本培养液培养MSCs,实验组用条件培养液诱导培养MSCs。通过显微镜下动态观察、HE染色、免疫组化等方法观察诱导结果。结果①获得纯化的MSCs;②动态观察培养细胞具有不断增殖的干细胞特性,HE染色细胞呈梭形,透射电镜观察细胞较幼稚,免疫组化检测细胞表面标记CD44、CD90呈阳性,从而鉴定了MSCs;③MSCs培养上清中IL6、IL8、G CSF、SCF等的含量显著高于对照组(P<0.05);④实验组细胞形态发生变化,CD29、CD117和Oct4免疫组化染色阳性;对照组细胞形态不变,CD29、CD117和Oct4免疫组化染色阴性。结论①用Percoll密度梯度离心法和贴壁法相结合的方法可获得纯化的MSCs;②

Isolation and Culture of Mouse Marrow Mesenchymal Stem Cells(MSCs) and Biological Characteristics of MSCs Cultured in Conditions for Spermatogonia in vitro

Objective: To isolate, culture and purify mouse bone marrow mesenchymal stem cells(MSCs) and observe the main biological characteristics of MSCs cultured in conditions for spermatogonia in vitro. Methods: The tibias and femurs were dissected from 5~6-week old mice and the marrow in the tibias and femurs was flushed out with medium. MSCs were isolated, cultured, purified in vitro by Percoll density gradient centrifugation combined with adherent method and identified by dynamic observation of stem cell characteristics by transmission electron microscope, HE staining, and immunohistochemical detection of cell markers. The quantities of such cytokines as IL-6,IL-8, G-CSF and SCF in culture liquid with MSCs were measured by ELISA, and compared with those of the control group. MSCs of the third generation were divided into two groups to be induced and cultured. MSCs of the control group were cultured with basal medium, while those of the experimental group with conditional medium. The results were analysed by microscopic observation, HE staining and immunohistochemical methods. Results: Pure MSCs were obtained. The cultured cells, with stem cell characteristics, shuttle-shaped at HE staining, immature under the transmission electron microscope and CD44 and CD90 positive by immunohistochemical detection, could be identified as MSCs. Compared with the control group, the quantities of IL-6, IL-8, G-CSF and SCF in the experimental group increased significantly(P<~0.05 ). The shapes of MSCs changed and immunohistochemical staining for CD27, CD119 and Oct-4 was positive in the experimental group, but both were just the opposite in the control group. Conclusion: Pure MSCs can be obtained by Percoll density gradient centrifugation combined with adherent method and identified by dynamically observing stem cell characteristics, HE staining, observation under the transmission electron microscope and immunohistochemical detection of cell markers. MSCs can secrete cytokines such as IL-6, IL-8, G-CSF, SCF, and so on. MSCs cultured in conditions for spermatogonia may show some biological characteristics of spermatogonia.