Levy R, Benchaib M, Cordonier H, Souchier C, Guerin J F
Laboratoire de Biologie de la Reproduction et du Développement, Hôpital Edouard Herriot, Lyon, France.
Mol Hum Reprod. 1998 Aug;4(8):775-83. doi: 10.1093/molehr/4.8.775.
Confocal laser scanning microscopy was used to observe human arrested and fragmented preimplantation embryos obtained by in-vitro fertilization. Observation of the cellular actin cortex and chromatin showed a high frequency of embryos with blastomeres exhibiting two or more nuclei, while others had nuclei displaying chromatin condensation and fragmentation patterns. Many of the abnormal chromatin images could be due to the process of programmed cell death (apoptosis). The possible link between abnormalities of the blastomeres and apoptosis was investigated using two detection methods for cells undergoing apoptosis. Detection of phosphatidylserine exposure was performed using annexin V; the chromosomal breakdown preceding the nuclear collapse of apoptotic nuclei was tested using the terminal transferase-mediated DNA end labelling (TUNEL) assay. Annexin V staining was observed in all arrested and/or fragmented human embryos, but not in cryopreserved embryos which continued to develop normally after thawing. The TUNEL assay was positive in 30% (15/50) of arrested embryos, all of which had cytoplasmic fragments. In contrast, embryos showing regular size blastomeres without fragments were TUNEL negative.
利用共聚焦激光扫描显微镜观察通过体外受精获得的人类停滞和碎片化的植入前胚胎。对细胞肌动蛋白皮质和染色质的观察显示，许多胚胎的卵裂球出现两个或更多细胞核的频率较高，而其他胚胎的细胞核则呈现染色质浓缩和碎片化模式。许多异常的染色质图像可能归因于程序性细胞死亡（凋亡）过程。使用两种针对凋亡细胞的检测方法研究了卵裂球异常与凋亡之间的可能联系。使用膜联蛋白V检测磷脂酰丝氨酸暴露情况；使用末端转移酶介导的DNA末端标记（TUNEL）试验检测凋亡细胞核核崩解之前的染色体断裂情况。在所有停滞和/或碎片化的人类胚胎中均观察到膜联蛋白V染色，但在冷冻保存后仍能正常发育的胚胎中未观察到。TUNEL试验在30%（15/50）的停滞胚胎中呈阳性，所有这些胚胎都有细胞质碎片。相比之下，卵裂球大小正常且无碎片的胚胎TUNEL试验呈阴性。
