Laboratory of Reproductive Biology, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark.
Department of Urology, Selcuk University School of Medicine, 42250 Konya, Turkey.
Hum Reprod Update. 2020 Apr 15;26(3):368-391. doi: 10.1093/humupd/dmaa003.
Although the prognosis of childhood cancer survivors has increased dramatically during recent years, chemotherapy and radiation treatments for cancer and other conditions may lead to permanent infertility in prepubertal boys. Recent developments have shown that spermatogonial stem cell (SSC) transplantation may be a hope for restoring fertility in adult survivors of childhood cancers. For this reason, several centres around the world are collecting and cryopreserving testicular tissue or cells anticipating that, in the near future, some patients will return for SSC transplantation. This review summarizes the current knowledge and utility of SSC transplantation techniques.
The aim of this narrative review is to provide an overview of the currently used experimental injection techniques for SSC transplantation in animal and human testes. This is crucial in understanding and determining the role of the different techniques necessary for successful transplantation.
A comprehensive review of peer-reviewed publications on this topic was performed using the PubMed and Google Scholar databases. The search was limited to English language work and studies between 1994 (from the first study on SSC transplantation) and April 2019. Key search terms included mouse, rat, boar, ram, dog, sheep, goat, cattle, monkey, human, cadaver, testes, SSC transplantation, injection and technique.
This review provides an extensive clinical overview of the current research in the field of human SSC transplantation. Rete testis injection with ultrasonography guidance currently seems the most promising injection technique thus far; however, the ability to draw clear conclusions is limited due to long ischemia time of cadaver testis, the relatively decreased volume of the testis, the diminishing size of seminiferous tubules, a lack of intratesticular pressure and leakage into the interstitium during the injection on human cadaver testis. Current evidence does not support improved outcomes from multiple infusions through the rete testes. Overall, further optimization is required to increase the efficiency and safety of the infusion method.
Identifying a favourable injection method for SSC transplantation will provide insight into the mechanisms of successful assisted human reproduction. Future research could focus on reducing leakage and establishing the optimal infusion cell concentrations and pressure.
尽管近年来儿童癌症幸存者的预后有了显著改善，但癌症和其他疾病的化疗和放疗可能导致青春期前男孩永久性不育。最近的发展表明，精原干细胞（SSC）移植可能是恢复儿童癌症成年幸存者生育能力的希望。出于这个原因，世界各地的几个中心正在收集和冷冻保存睾丸组织或细胞，预计在不久的将来，一些患者将返回进行 SSC 移植。这篇综述总结了 SSC 移植技术的最新知识和应用。
本叙述性综述的目的是概述目前用于动物和人类睾丸中 SSC 移植的实验性注射技术。这对于理解和确定成功移植所需的不同技术的作用至关重要。
使用 PubMed 和 Google Scholar 数据库对该主题的同行评审出版物进行了全面综述。搜索仅限于英语工作和 1994 年（第一个 SSC 移植研究）至 2019 年 4 月期间的研究。关键搜索词包括小鼠、大鼠、猪、公羊、狗、绵羊、山羊、牛、猴子、人类、尸体、睾丸、SSC 移植、注射和技术。
本综述提供了人类 SSC 移植领域当前研究的广泛临床概述。目前，经睾丸网超声引导注射似乎是迄今为止最有前途的注射技术；然而，由于尸体睾丸的缺血时间长、睾丸相对体积减小、生精小管尺寸减小、注射时针头内缺乏间质压力和漏入间质，因此很难得出明确的结论。目前的证据并不支持通过睾丸网多次注射来提高疗效。总体而言，需要进一步优化输注方法以提高效率和安全性。
确定有利于 SSC 移植的注射方法将为成功辅助人类生殖的机制提供深入了解。未来的研究可以集中在减少渗漏以及确定最佳输注细胞浓度和压力上。
