Raliou Mariam, Meyerholz-Wohllebe Marie Margarete, Dembélé Doulaye, Mense Kirsten, Heppelmann Maike, Richard Christophe, Chavatte-Palmer Pascale, Dieuzy-Labaye Isabelle, Smith David, Zieger Peter, Schuberth Hans-Joachim, Schmicke Marion, Sheldon Iain Martin, Sandra Olivier
Université Paris-Saclay, UVSQ, INRAE, BREED, Jouy-en-Josas, France.
Ecole Nationale Vétérinaire d'Alfort, BREED, Maisons-Alfort, France.
PLoS One. 2025 Sep 15;20(9):e0330701. doi: 10.1371/journal.pone.0330701. eCollection 2025.
The bovine endometrium undergoes cellular, molecular, and functional changes to support embryo survival and development to term. These changes involve a finely coordinated series of events at both local and systemic levels. We postulated that circulating white blood cells (WBCs) could provide valuable biomarkers for predicting pregnancy success in heifers undergoing embryo transfer, when, sampled during both a preconception cycle and a conception cycle, before embryo transfer takes place. WBCs were isolated using PAXgene Blood RNA tubes collected from Holstein-Friesian heifers on Days 7 and 14 of a preconception estrous cycle (PCD7 and PCD14) and, after a rest cycle, on Day 7 of the subsequent estrous cycle (1ETD7) just before embryo transfer. Circulating progesterone and estrogens were assayed and pregnancy was confirmed by either uterine flushing and conceptus collection on Day 18 post-estrus, or the delivery of a healthy calf. Using a custom bovine gene expression microarray representing 19,479 unique transcript, comparison of transcriptomes between heifers classified as non-pregnant or pregnant revealed 1,240, 896 and 1,023 differentially expressed genes (DEGs) at PCD7, PCD14 and 1ETD7 respectively. Our bioinformatics analyses revealed that pregnancy failure after embryo transfer was associated with upstream regulators, biological functions, canonical pathways and gene networks related to inflammation, immunity, apoptosis and cell death regulation, cell proliferation, membrane compounds, lipid metabolism, oxygen transport and ions transport. The heifers classified as non-pregnant showed significant increased transcripts levels of PTGR1 at the three time points (PCD7, PCD14 and 1ETD7), AIF1 at PCD14, FNDC3B, IL15 and SERPINE1 at 1ETD7. Our findings highlight the potential of peripheral WBCs as a non-invasive source of biomarkers for predicting pregnancy outcomes, offering promising insights for improving pregnancy success when reproductive biotechnologies are used in mammalian females.
牛子宫内膜会发生细胞、分子和功能变化，以支持胚胎存活并发育至足月。这些变化涉及局部和全身水平上一系列精细协调的事件。我们推测，在胚胎移植前的孕前周期和受孕周期进行采样时，循环白细胞（WBC）可为预测接受胚胎移植的小母牛的妊娠成功率提供有价值的生物标志物。使用从荷斯坦-弗里生小母牛在孕前发情周期的第7天和第14天（PCD7和PCD14）收集的PAXgene Blood RNA管分离白细胞，经过一个休息周期后，在随后发情周期的第7天（1ETD7），即胚胎移植前分离白细胞。测定循环孕酮和雌激素，并通过发情后第18天子宫冲洗和收集孕体或分娩健康小牛来确认妊娠。使用代表19479个独特转录本的定制牛基因表达微阵列，比较分类为未怀孕或怀孕的小母牛之间的转录组，分别在PCD7、PCD14和1ETD7发现了1240、896和1023个差异表达基因（DEG）。我们的生物信息学分析表明，胚胎移植后的妊娠失败与上游调节因子、生物学功能、与炎症、免疫、细胞凋亡和细胞死亡调节、细胞增殖、膜化合物、脂质代谢、氧运输和离子运输相关的典型途径和基因网络有关。分类为未怀孕的小母牛在三个时间点（PCD7、PCD14和1ETD7）的PTGR1转录本水平显著增加，在PCD14时AIF1增加，在1ETD7时FNDC3B、IL15和SERPINE1增加。我们的研究结果突出了外周白细胞作为预测妊娠结局的非侵入性生物标志物来源的潜力，为在哺乳动物雌性中使用生殖生物技术时提高妊娠成功率提供了有前景的见解。
