EA 4308 Spermatogenesis and Male Gamete Quality, Reproductive Biology Laboratory-CECOS, Rouen University Hospital, University of Rouen, Rouen, France.
Hum Reprod. 2011 Jan;26(1):47-58. doi: 10.1093/humrep/deq297. Epub 2010 Nov 18.
Spermatozoa with large vacuoles (SLV) may have a negative impact on embryo development. The origin of these vacuoles is unknown. We evaluated acrosome and nucleus alterations in isolated SLV, versus unselected spermatozoa.
We studied 20 patients with teratozoospermia. Spermatozoa from the native semen sample and spermatozoa presenting a vacuole occupying >13.0% total head area, isolated under high magnification (×6600), were assessed. Confocal and transmission electron microscope evaluations were performed on SLV and native sperm, respectively. Acrosome morphology and DNA fragmentation were analysed using proacrosin immunolabelling (monoclonal antibody 4D4) and terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assay. Chromatin condensation was evaluated with aniline blue staining. Sperm aneuploidy was assessed using fluorescence in situ hybridization.
SLV represented 38.0 ± 5.10% of motile spermatozoa obtained after gradient density centrifugation. Vacuoles were mainly in the anterior and median sperm head (45.7 ± 2.90 and 46.1 ± 3.00%, respectively). Abnormal acrosomes were increased in SLV compared with unselected spermatozoa (77.8 ± 2.49 versus 70.6 ± 2.62%; P = 0.014). Microscopic observations showed an exclusively nuclear localization of large vacuoles. Complete DNA fragmentation was higher in native spermatozoa (P < 0.0001) than SLV, while chromatin condensation was altered in SLV (P < 0.0001). Aneuploidy and diploidy rates were increased in SLV (P < 0.0001).
Sperm vacuoles were exclusively nuclear. In our selected teratozoospermic population, aneuploidy and chromatin condensation defects were the main alterations observed in SLV. Based on results from this small sample of spermatozoa, we propose a global impairment of the spermatogenesis process as a common origin of the morphological alterations.
具有大空泡的精子（SLV）可能对胚胎发育产生负面影响。这些空泡的来源尚不清楚。我们评估了分离的 SLV 与未经选择的精子的顶体和核的改变。
我们研究了 20 例畸形精子症患者。从原生精液样本中分离出顶体和空泡占据头部总面积 >13.0%的精子，在高倍镜（×6600）下分离。对 SLV 和原生精子进行共焦和透射电子显微镜评估。使用脯氨酸酶免疫标记（单克隆抗体 4D4）和末端脱氧核苷酸转移酶介导的 dUTP 缺口末端标记检测分析顶体形态和 DNA 碎片化。用苯胺蓝染色评估染色质浓缩。使用荧光原位杂交评估精子非整倍体。
梯度密度离心后获得的活动精子中，SLV 占 38.0±5.10%。空泡主要位于精子头的前和中部（分别为 45.7±2.90%和 46.1±3.00%）。与未经选择的精子相比，SLV 中的异常顶体增加（77.8±2.49%比 70.6±2.62%；P=0.014）。显微镜观察显示大空泡仅位于核内。原生精子中的完全 DNA 碎片化高于 SLV（P<0.0001），而 SLV 中的染色质浓缩发生改变（P<0.0001）。SLV 中的非整倍体和二倍体率增加（P<0.0001）。
精子空泡仅位于核内。在我们选择的畸形精子症人群中，非整倍体和染色质浓缩缺陷是 SLV 中观察到的主要改变。基于对这一小部分精子的结果，我们提出了一个普遍的生精过程受损作为形态改变的共同起源。
