类胚体诱导脐带间充质干细胞向生殖细胞的分化

背景：脐带间充质干细胞能否在体外和体内微环境条件下衍生为卵母细胞，对女性生殖的维持及卵母细胞的再生均具有十分重要的意义。目的：进一步验证体外微环境类胚体对脐带间充质干细胞向生殖细胞分化的影响。方法：将脐带间充质干细胞进行悬滴培养，使其形成类胚体，进而采用将类胚体与人或小鼠卵巢颗粒细胞共培养、卵泡液条件培养基培养等方法，体外诱导脐带间充质干细胞向早期生殖细胞分化。结果与结论：①将脐带间充质干细胞进行悬滴培养，其能够形成类胚体。②流式细胞仪检测结果：类胚体形成5 d后，其中SSEA-1阳性细胞占15.61%。③免疫组织化学检测结果：形成5 d的类胚体与人或小鼠的卵巢颗粒细胞共培养，10 d后生殖系标记物SCP3、生长分化因子9阳性表达，而颗粒细胞及采用卵泡液培养的类胚体均无表达。结果表明，脐带间充质干细胞体外悬滴培养可形成类胚体，与人或小鼠卵巢颗粒细胞共培养后均表达生殖系特异性标记物。

Differentiation of human umbilical cord mesenchymal stem cells into germ cells induced by embryoid bodies

BACKGROUND:Whether umbilical mesenchymal stem cells (UC-MSCs) can be induced into oocytes under in vitro and in vivo microenvironment is very important for female reproductive maintenance and oocyte regeneration.OBJECTIVE:To further testify the effects of embryonic bodies (EB) under in vitro microenvironment on the differentiation of UC-MSCs into germ cells.METHODS:UC-MSCs were cultured in hanging drop to form EB, which were co-cultured with human ovarian granulosa cells or mouse ovarian granulosa cells, or were cultured in follicular fluid to induce differentiation of UC-MSCs into primary germ cells in vitro.RESULTS AND CONCLUSION:The EB were successfully prepared when UC-MSCs were cultured in hanging drop. Flow cytometry results: SSEA-1+ cells accounted for 15.61% after 5 days of EB formation. The results of immunohistochemistry: EB of 5 days were co-cultured with human ovarian granulosa cells or mouse ovarian granulosa cells for 10 days, germ-line markers of synaptonemal complex protein-3 and growth differentiation factor-9 positively expressed, while these two markers did not express in granule cells or EB cultured in follicular fluid. EB can be formed when UC-MSCs are cultured in hanging drop in vitro. Germ-line markers will express in EB when they are co-cultured with human ovarian granulosa cells or mouse ovarian granulosa cells.