Sathananthan A H
Latrobe University, Carlton, Australia.
Baillieres Clin Obstet Gynaecol. 1994 Mar;8(1):141-56. doi: 10.1016/s0950-3552(05)80029-x.
The processes of abnormal sperm penetration and incorporation into human oocytes during IVF and after sperm microinjection, assessed by TEM, are reviewed. A spectrum of morphologically abnormal sperm with head, neck and midpiece defects penetrate the egg vestments of oocytes (1-3 h after insemination with sperm from normal donors) in both unfertilized and normally fertilized oocytes. Sperm with aberrant head shapes, acrosomal and nuclear defects penetrate the outer zona pellucida but are rarely encountered in the inner zona and perivitelline space, showing that the zona prevents abnormal sperm penetration. Grossly abnormal sperm are, however, incorporated into the ooplasm of zona-denuded oocytes. Microinjection of poor-quality sperm from male-factor patients into the perivitelline space or directly into the ooplasm of oocytes also reveals a variety of structural defects conforming to those observed in washed sperm pellets, highlighting the difficulties of selection of 'normal' sperm for microinjection. Abnormal sperm have been seen to interact and fuse with the oocyte in the perivitelline space, and to be incorporated into the ooplasm. Those with nuclear and neck (centriolar) defects are of particular significance, as they might contribute to aberrant development. The functional competence of immotile, round-headed and epididymal sperm is also briefly discussed.
本文通过透射电子显微镜（TEM）对体外受精（IVF）过程中以及精子显微注射后异常精子穿透并融入人类卵母细胞的过程进行了综述。一系列形态异常的精子，包括头部、颈部和中段缺陷，在未受精和正常受精的卵母细胞中（用正常供体精子授精后1 - 3小时）均可穿透卵母细胞的卵膜。头部形状异常、顶体和核缺陷的精子可穿透透明带外层，但在透明带内层和卵周隙中很少见，这表明透明带可阻止异常精子穿透。然而，严重异常的精子可融入去除透明带的卵母细胞的卵质中。将男性因素患者的低质量精子显微注射到卵周隙或直接注射到卵母细胞的卵质中，也发现了与洗涤后的精子沉淀中观察到的各种结构缺陷一致的情况，这突出了为显微注射选择“正常”精子的困难。已观察到异常精子在卵周隙中与卵母细胞相互作用并融合，并融入卵质中。那些具有核和颈部（中心粒）缺陷的精子具有特别重要的意义，因为它们可能导致异常发育。本文还简要讨论了不动、圆头和附睾精子的功能能力。
