Kim S Samuel, Kang Hee Gyu, Kim Nam Hyung, Lee Hoi Chang, Lee Hyang Heun
Department of OB/GYN, Eulji University School of Medicine, Seoul, Korea.
Hum Reprod. 2005 Sep;20(9):2502-8. doi: 10.1093/humrep/dei099. Epub 2005 Jun 9.
Previous studies showed that immature oocytes stored in ovarian tissue could develop to the mature stage after transplantation. However, the quality and competency of the oocytes developed in xenografted ovarian tissue have never been investigated. As a pilot study to investigate this uncharted issue, we evaluated microtubule organization and chromatin configuration of human oocytes harvested from xenografted frozen-thawed ovarian tissue.
Frozen-thawed human ovarian tissue was transplanted into severe combined immunodeficient mice. All animals were stimulated with gonadotrophin from 20 weeks after transplantation. Grafts were recovered 36 h after hCG administration. The oocytes were retrieved from the antral follicles (>2 mm diameter), cultured in vitro, stained for microtubule and chromatin localization.
Five oocytes from 21 female mice and seven oocytes from nine male mice were retrieved. Immunocytochemical examinations of these oocytes after in vitro maturation revealed only two developed to the metaphase II stage. Most oocytes were between prophase and metaphase with abnormal microtubule organization and chromatin configuration.
Immature oocytes in stored human ovarian tissue can grow to maturity in host animals after xenotransplantation. Retrieval of oocytes from the xenograft can be carried out and is reproducible. However, many oocytes, grown in host animals and further matured in vitro, showed aberrant microtubule organization and chromatin patterns.
先前的研究表明，储存在卵巢组织中的未成熟卵母细胞在移植后可发育至成熟阶段。然而，异种移植卵巢组织中发育的卵母细胞的质量和能力从未被研究过。作为一项探索这一未知问题的初步研究，我们评估了从异种移植的冻融卵巢组织中获取的人类卵母细胞的微管组织和染色质构型。
将冻融的人类卵巢组织移植到严重联合免疫缺陷小鼠体内。所有动物在移植后20周开始用促性腺激素刺激。在注射hCG后36小时回收移植物。从直径>2mm的窦状卵泡中获取卵母细胞，进行体外培养，对微管和染色质定位进行染色。
从21只雌性小鼠中获取了5个卵母细胞，从9只雄性小鼠中获取了7个卵母细胞。对这些卵母细胞进行体外成熟后的免疫细胞化学检查发现，只有2个发育至中期II阶段。大多数卵母细胞处于前期和中期之间，微管组织和染色质构型异常。
储存的人类卵巢组织中的未成熟卵母细胞在异种移植后可在宿主动物体内生长至成熟。可以从异种移植物中获取卵母细胞，且该过程具有可重复性。然而，许多在宿主动物体内生长并在体外进一步成熟的卵母细胞显示出异常的微管组织和染色质模式。
