重复植入失败是健康女性不孕的主要原因之一。子宫内β-连接素（CTNNB1）在植入过程中发挥关键作用。然而，胚胎CTNNB1在植入过程中的作用尚不清楚。我们通过分析携带Ctnnb1缺陷（Ctnnb1Δ/Δ）胚胎的小鼠来探讨这个问题。Ctnnb1Δ/Δ胚胎是由携带Ctnnb1缺陷的卵子和精子交配产生的。我们发现，Ctnnb1Δ/Δ胚胎发育到囊胚阶段后，被吸收了，留下了空的蜕膜囊。此外，对植入至关重要的子宫因子白血病抑制因子在Ctnnb1Δ/Δ囊胚中无法检测到。此外，决定滋养层细胞命运的转录因子CDX2在Ctnnb1Δ/Δ囊胚中没有观察到。宫内注射子宫液（来自对照小鼠）和重组鼠白血病抑制因子蛋白质使子宫对Ctnnb1Δ/Δ囊胚产生了反应。这些结果表明，胚胎CTNNB1是分泌囊胚源性因子以打开植入窗口所必需的，而通过使用补充材料，可以诱导子宫对植入的反应。因此，我们的结果可能有助于发现类似的机制在人类中，从而更好地理解重复植入失败的病因。版权所有©2022年美国和加拿大病理学院。由Elsevier公司出版。保留所有权利。

Repeated implantation failure is a major cause of infertility among healthy women. Uterine β-catenin (CTNNB1) plays a critical role in implantation. However, the role of embryonic CTNNB1 during implantation remains unclear. We addressed this topic by analyzing mice carrying Ctnnb1-deficient (Ctnnb1Δ/Δ) embryos. Ctnnb1Δ/Δ embryos were produced by intercrossing mice bearing Ctnnb1-deficient eggs and sperms. We found that Ctnnb1Δ/Δ embryos developed to the blastocyst stage; thereafter, they were resorbed, leaving empty decidual capsules. Moreover, leukemia inhibitory factor, a uterine factor essential for implantation, was undetectable in Ctnnb1Δ/Δ blastocysts. Furthermore, CDX2, a transcription factor that determines the fate of trophectoderm cells, was not observed in Ctnnb1Δ/Δ blastocysts. Intrauterine injection with uterine fluids (from control mice) and recombinant mouse leukemia inhibitory factor proteins rescued the uterine response to Ctnnb1Δ/Δ blastocysts. These results suggest that embryonic CTNNB1 is required for the secretion of blastocyst-derived factor(s) that open the implantation window, indicating that the uterine response to implantation can be induced using supplemental materials. Therefore, our results may contribute to the discovery of a similar mechanism in humans, leading to a better understanding of the pathogenesis of repeated implantation failure.Copyright © 2022 United States & Canadian Academy of Pathology. Published by Elsevier Inc. All rights reserved.