Department of Gynecology, Université Catholique de Louvain, Cliniques Universitaires St Luc, Avenue Hippocrate 10, Brussels, Belgium.
Hum Reprod Update. 2010 May-Jun;16(3):312-28. doi: 10.1093/humupd/dmp054. Epub 2010 Jan 4.
Fertility in adult life may be severely impaired by gonadotoxic therapies. For young boys who do not yet produce spermatozoa, cryopreservation of immature testicular tissue (ITT) is an option to preserve their fertility, albeit still experimental. This paper covers current options for ITT cryopreservation and fertility restoration.
Relevant studies were identified by an extensive Medline search of English and French language articles. Search terms were: gonadotoxicity, cytoprotection, cryopreservation, ITT, spermatogonia, testicular transplantation, testicular grafting and in vitro maturation (IVM).
Although no effective gonadoprotective drug is yet available for in vivo spermatogonial stem cell protection in humans, current evidence supports the feasibility of ITT cryopreservation before gonadotoxic treatment with a view to fertility preservation. Controlled slow freezing with dimethyl sulfoxide allows survival and proliferation of human spermatogonia after xenotransplantation, but only partial differentiation. Animal data look promising, since healthy offspring have been obtained after transplantation of frozen testicular cell suspensions or tissue pieces. However, none of the fertility restoration options from frozen tissue, i.e. cell suspension transplantation, tissue grafting and IVM have proved efficient and safe in humans as yet.
While additional evidence is required to define optimal conditions for ITT cryopreservation with a view to transplantation or IVM, the putative indications for such techniques, as well as their limitations according to disease, are outlined.
性腺毒性疗法可能严重损害成年后的生育能力。对于尚未产生精子的年轻男孩，冷冻保存未成熟睾丸组织（ITT）是保留生育能力的一种选择，尽管这仍然是实验性的。本文介绍了 ITT 冷冻保存和生育力恢复的当前选择。
通过广泛的英文和法文文献的 Medline 搜索，确定了相关研究。搜索词为：性腺毒性、细胞保护、冷冻保存、ITT、精原细胞、睾丸移植、睾丸移植和体外成熟（IVM）。
尽管目前尚无有效的性腺保护药物可用于体内精原干细胞保护，但现有证据支持在性腺毒性治疗前进行 ITT 冷冻保存以保留生育能力。二甲亚砜的控制性慢速冷冻允许人类精原细胞在异种移植后存活和增殖，但仅部分分化。动物数据看起来很有希望，因为已经从冷冻睾丸细胞悬液或组织片移植中获得了健康的后代。然而，迄今为止，从冷冻组织中获得的任何生育力恢复选择，即细胞悬液移植、组织移植和 IVM，在人类中都没有被证明是有效和安全的。
虽然需要更多的证据来确定 ITT 冷冻保存的最佳条件，以便进行移植或 IVM，但根据疾病概述了这些技术的潜在适应症及其局限性。
