Yu Bo, van Tol Helena T A, Stout Tom A E, Roelen Bernard A J
Farm Animal Health, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.
Equine Sciences, Department Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.
Front Cell Dev Biol. 2021 Jan 5;8:616801. doi: 10.3389/fcell.2020.616801. eCollection 2020.
The presence of cellular fragments in the perivitelline space is a commonly used parameter to determine quality before transfer of produced (IVP) embryos. However, this parameter is difficult to assess after blastocyst expansion. In this study, we used mechanical hatching to confirm the presence of cellular fragments in the perivitelline space of bovine IVP blastocysts. We further looked for associations between possible apoptosis within extruded cells/ cellular fragments and the quality of bovine blastocysts using quantitative RT-PCR and immunofluorescence. Surprisingly, more than 42% of expanded blastocysts had cellular fragments in the perivitelline space; however, more than 37% of extruded cells were TUNEL negative. We observed no significant difference in embryo quality between expanded blastocysts with and without cellular fragments in the perivitelline space. Overall, our data suggest that embryos extrude abnormal cells to maintain their developmental potential. The presence of fragmented cells is not an indicator of embryo quality.
卵周隙中细胞碎片的存在是评估体外生产（IVP）胚胎移植前质量的常用参数。然而，在囊胚扩张后，这个参数很难评估。在本研究中，我们采用机械孵化法来确认牛IVP囊胚卵周隙中细胞碎片的存在。我们进一步利用定量逆转录聚合酶链反应（RT-PCR）和免疫荧光技术，寻找挤出细胞/细胞碎片中可能存在的凋亡与牛囊胚质量之间的关联。令人惊讶的是，超过42%的扩张囊胚在卵周隙中有细胞碎片；然而，超过37%的挤出细胞TUNEL检测呈阴性。我们观察到卵周隙中有细胞碎片和没有细胞碎片的扩张囊胚在胚胎质量上没有显著差异。总体而言，我们的数据表明胚胎会排出异常细胞以维持其发育潜力。细胞碎片的存在并非胚胎质量的指标。
