Laboratorio de Biología de la Reproducción en Mamíferos, Centro de Estudios Farmacológicos y Botánicos (CEFYBO), Universidad de Buenos Aires/CONICET, Buenos Aires, Argentina.
PROCREARTE- Red de Medicina Reproductiva y Molecular, Buenos Aires, Argentina.
PLoS One. 2022 Aug 2;17(8):e0271729. doi: 10.1371/journal.pone.0271729. eCollection 2022.
Sperm selection for assisted reproduction techniques is generally based on basic parameters, while key aspects of sperm competence and its journey from the deposition site to the fertilization site are overlooked. Consequently, identifying molecular markers in spermatozoa that can efficiently predict the fertility of a semen sample could be of great interest, particularly in cases of idiopathic male infertility. When spermatozoa reach the female reproductive tract, it provides to them the cellular and molecular microenvironment needed to acquire fertilizing ability. In this sense, considering the role that integrin α5β1 of spermatozoa plays in reproduction-related events, we investigated the correlation between the subcellular localization of sperm integrin α5β1 and early embryo development outcome after in vitro fertilization (IVF) procedures in human. Twenty-four semen samples from normozoospermic men and metaphase II (MII) oocytes from healthy women aged under 38 years, from couples who underwent IVF cycles, were used in this work. Sperm α5β1 localization was evaluated by immunofluorescence assay using an antibody against integrin α5 subunit. Integrin α5β1 was mainly localized in the sperm acrosomal region (45.33±7.89%) or the equatorial segment (30.12±7.43%). The early embryo development rate (data obtained from the Fertility Center) correlated positively with the localization of α5β1 in the acrosomal region (number of usable embryos / inseminated oocytes: ρ = 0.75; p<0.01 and number of usable embryos/total number of two pronuclear zygotes: ρ = 0.80; p<0.01). However, this correlation was not significant when the equatorial segment mark was evaluated. In addition, human sperm released from co-culture with bovine oviductal epithelial cells (BOEC) showed a significant enrichment in the acrosomal localization pattern of α5β1 compared to those sperm that were not co-cultured with BOEC (85.20±5.35% vs 35.00±17.09%, respectively, p<0.05). In conclusion, the evaluation of sperm integrin α5β1 immunolocalization could be a useful tool to select sperm with fertilizing ability from human semen samples before IVF procedures.
用于辅助生殖技术的精子选择通常基于基本参数，而精子功能的关键方面及其从沉积部位到受精部位的旅程却被忽视了。因此，鉴定精子中能够有效预测精液样本生育能力的分子标记物可能非常重要，尤其是在特发性男性不育的情况下。当精子到达女性生殖道时，它为精子提供了获得受精能力所需的细胞和分子微环境。从这个意义上说，考虑到精子整合素 α5β1 在与生殖相关的事件中所起的作用，我们研究了人类体外受精 (IVF) 程序后精子整合素 α5β1 的亚细胞定位与早期胚胎发育结果之间的相关性。这项工作使用了来自 24 名正常精子男性和 18 岁以下健康女性的中期 II (MII) 卵母细胞的精液样本，这些卵母细胞来自接受 IVF 周期的夫妇。使用针对整合素 α5 亚单位的抗体通过免疫荧光测定法评估精子 α5β1 的定位。整合素 α5β1 主要定位于精子顶体区域 (45.33±7.89%) 或赤道段 (30.12±7.43%)。(从生育中心获得的数据)早期胚胎发育率与顶体区域的 α5β1 定位呈正相关(可用于胚胎/授精卵数:ρ=0.75;p<0.01 和可用于胚胎/总双核受精卵数:ρ=0.80;p<0.01)。然而，当评估赤道段标记时，这种相关性并不显著。此外，与人牛输卵管上皮细胞 (BOEC) 共培养后释放的人精子与未与 BOEC 共培养的精子相比，α5β1 的顶体定位模式明显富集 (85.20±5.35%对 35.00±17.09%，分别，p<0.05)。总之，在 IVF 程序之前，评估精子整合素 α5β1 的免疫定位可能是从人类精液样本中选择具有受精能力的精子的有用工具。
