Sakkas D, Urner F, Bizzaro D, Manicardi G, Bianchi P G, Shoukir Y, Campana A
Department of Obstetrics and Gynaecology, University Hospital of Geneva, Switzerland.
Hum Reprod. 1998 Dec;13 Suppl 4:11-9. doi: 10.1093/humrep/13.suppl_4.11.
In the first part of this report we investigate whether chromatin anomalies in human spermatozoa can influence fertilization after intracytoplasmic sperm injection (ICSI). We have examined the sperm chromatin packaging quality using the chromomycin A3 (CMA3) fluorochrome and the presence of DNA damage in spermatozoa using in-situ nick translation. When comparing the spermatozoa of patients undergoing in-vitro fertilization (IVF) and ICSI distinct differences are evident in that ICSI males have a higher CMA3 fluorescence, indicating spermatozoa with loosely packed chromatin, and more spermatozoa containing endogenous DNA nicks. When examining the unfertilized oocytes of ICSI patients we found that men who had a high percentage of anomalies in their chromatin, i.e. > 30% CMA3 fluorescence and > 10% nicks, had more than double the number of unfertilized oocytes containing spermatozoa that had remained condensed. The observation that failed fertilized oocytes, injected with spermatozoa from patients with a higher percentage of sperm nuclear anomalies, contain more condensed spermatozoa indicates that a selection process against these spermatozoa may be in place at the time of fertilization. In the second part of the study we show that spare ICSI embryos have significantly lower rates of development to the blastocyst stage compared with those developed after routine IVF. These results show that a greater understanding of the molecular basis of male infertility is therefore needed to broaden our knowledge on the effect that abnormal spermatozoa have on fertilization and embryo development.
在本报告的第一部分，我们研究了人类精子中的染色质异常是否会影响卵胞浆内单精子注射（ICSI）后的受精情况。我们使用放线菌素A3（CMA3）荧光染料检测了精子染色质包装质量，并通过原位缺口平移检测了精子中的DNA损伤情况。比较接受体外受精（IVF）和ICSI的患者的精子时，明显存在差异，即接受ICSI的男性精子具有更高的CMA3荧光，表明染色质包装松散的精子更多，且含有内源性DNA缺口的精子更多。检查ICSI患者未受精的卵母细胞时，我们发现染色质异常比例高的男性，即CMA3荧光>30%且缺口>10%的男性，其未受精卵母细胞中含有仍呈凝聚状态精子的数量是其他男性的两倍多。用精子核异常比例较高的患者的精子注射后未受精的卵母细胞中含有更多凝聚精子的观察结果表明，受精时可能存在针对这些精子的选择过程。在研究的第二部分，我们表明与常规IVF后发育的胚胎相比，备用的ICSI胚胎发育到囊胚阶段的比率显著更低。因此，这些结果表明，需要更深入地了解男性不育的分子基础，以拓宽我们对异常精子对受精和胚胎发育影响的认识。
