Vanderzwalmen P, Nijs M, Stecher A, Zech H, Bertin G, Lejeune B, Vandamme B, Chatziparasidou A, Prapas Y, Schoysman R
Schoysman Infertility Management Foundation, Vilvoorde, Belgium.
Hum Reprod. 1998 Dec;13 Suppl 4:71-84. doi: 10.1093/humrep/13.suppl_4.71.
Microinjection of spermatids into oocytes has proven to be a successful assisted reproduction procedure in the animal model. In the human, low fertilization and cleavage to the 4-cell stage were reported after intracytoplasmic sperm injection (ICSI) with round spermatids. In comparison with a conventional ICSI-testicular sperm extraction (TESE) programme, the implantation rate after round spermatid injection is dramatically low. Different problems have been encountered during the development of the spermatid injection technique and they could be partially responsible for the lower outcome when using round spermatids. Compared with the round spermatid cells, spermatids in the elongation phase are easy to isolate and identify from other round cells present in a wet preparation. The morphological identification does not reveal anything about the viability or the genetic normality of the round spermatids. Severe testicular dysfunction may have consequences on the quality of the few spermatogenic cells present. Others factors, such as the pathology of the patient, play an important role in the successful treatment. Even if the results are extremely low, spermatid injection seems more favourable for men who have already proven their capacity to produce some spermatozoa. A spermatogenic block at the round spermatid level has led to early abortions, increasing the suspicion of the role of a genetic factor. In order for this technique to be safe for use in clinics, more intensive work is needed to improve the selection and handling of cells and to ascertain the genomic imprinting and gene expression necessary for embryonic development. Hence, when using immature cells for conception, the screening of the patient and the follow-up of the pregnancies and babies should be mandatory.
在动物模型中，将精子细胞显微注射到卵母细胞中已被证明是一种成功的辅助生殖程序。在人类中，报道了用圆形精子细胞进行胞浆内单精子注射（ICSI）后受精率低且胚胎发育至4细胞阶段的情况。与传统的ICSI-睾丸精子提取（TESE）程序相比，圆形精子细胞注射后的着床率极低。在精子细胞注射技术的发展过程中遇到了各种问题，这些问题可能是导致使用圆形精子细胞时成功率较低的部分原因。与圆形精子细胞相比，伸长阶段的精子细胞易于从湿片制备中存在的其他圆形细胞中分离和识别。形态学鉴定无法揭示圆形精子细胞的活力或基因正常性。严重的睾丸功能障碍可能会对少量生精细胞的质量产生影响。其他因素，如患者的病理状况，在成功治疗中起着重要作用。即使结果极低，精子细胞注射对于已证明有产生一些精子能力的男性似乎更有利。圆形精子细胞水平的生精阻滞导致早期流产，这增加了对遗传因素作用的怀疑。为了使该技术在临床上安全使用，需要进行更深入的工作来改进细胞的选择和处理，并确定胚胎发育所需的基因组印记和基因表达。因此，当使用未成熟细胞进行受孕时，对患者的筛查以及对妊娠和婴儿的随访应该是强制性的。
