Department of Obstetrics and Gynecology, Northwestern University, Feinberg School of Medicine, 303 E. Superior Street, Chicago, IL 60611, USA.
Biol Reprod. 2010 Jun;82(6):1180-9. doi: 10.1095/biolreprod.109.082933. Epub 2010 Mar 3.
Cryopreservation of oocytes and embryos is commonly used to preserve fertility. However, women undergoing cancer treatment may not have the time or may not be good candidates for these options. Ovarian cortical tissue cryopreservation and subsequent tissue transplant has been proven successful yet inefficient in preserving larger secondary follicles, and is not recommended as a fertility preservation option for women with certain cancers. We evaluated cryopreservation of individual follicles as an alternative option in rodents, nonhuman primates, and human primates. Under optimal conditions, cryopreserved mouse secondary follicles were able to reestablish granulosa cell-oocyte interactions, which are essential for subsequent follicle growth. Individual secondary follicles survived cryopreservation, were able to be cultured in a three-dimensional alginate hydrogel matrix to the antral stage, and the enclosed oocytes were competent for fertilization. Using a vital imaging technique (pol-scope) employed in many fertility centers, we were able to bioassay the thawed, cultured follicles for the presence of transzonal connections between the somatic and germ cells. Perturbations in these linkages were shown to be reversed when follicles were cryopreserved under optimal freezing conditions. We applied the optimized cryopreservation protocol to isolated rhesus monkey and human secondary follicles, and using the birefringent bioassay, we were able to show good correlation between early follicle growth and healthy somatic cell-oocyte connections. Our results suggest that ovarian follicles can be cryopreserved, thawed, and analyzed noninvasively, making follicle preservation an additional option for young cancer patients.
卵母细胞和胚胎的冷冻保存通常用于保存生育能力。然而，正在接受癌症治疗的女性可能没有时间，或者可能不适合这些选择。卵巢皮质组织冷冻保存和随后的组织移植已被证明在保存较大的次级卵泡方面是成功的，但效率不高，不建议将其作为某些癌症女性的生育力保存选择。我们在啮齿动物、非人灵长类动物和人类灵长类动物中评估了作为替代方案的单个卵泡冷冻保存。在最佳条件下，冷冻保存的小鼠次级卵泡能够重新建立颗粒细胞-卵母细胞相互作用，这对于随后的卵泡生长至关重要。单个次级卵泡在冷冻保存后能够存活，可以在三维藻酸盐水凝胶基质中培养到腔前阶段，并且封闭的卵母细胞能够受精。使用许多生育中心采用的重要成像技术（pol-scope），我们能够对解冻的、培养的卵泡进行生物检测，以检测体-卵细胞之间是否存在跨带连接。当卵泡在最佳冷冻条件下冷冻保存时，这些连接的干扰被证明可以逆转。我们将优化的冷冻保存方案应用于分离的恒河猴和人次级卵泡，并使用双折射生物检测，我们能够显示出早期卵泡生长和健康的体细胞-卵母细胞连接之间的良好相关性。我们的结果表明，卵巢卵泡可以冷冻保存、解冻和非侵入性分析，这使得卵泡保存成为年轻癌症患者的另一种选择。
