The current coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2) remains a threat to pregnant women. However, the impact of early pregnancy SARS-CoV-2 infection on the maternal-fetal interface remains poorly understood. Here, we present a comprehensive analysis of single-cell transcriptomics and metabolomics in placental samples infected with SARS-CoV-2 during early pregnancy. Compared to control placentas, SARS-CoV-2 infection elicited immune responses at the maternal-fetal interface and induced metabolic alterations in amino acid and phospholipid profiles during the initial weeks post-infection. However, subsequent immune cell activation and heightened immune tolerance in trophoblast cells established a novel dynamic equilibrium that mitigated the impact on the maternal-fetal interface. Notably, the immune response and metabolic alterations at the maternal-fetal interface exhibited a gradual decline during the second trimester. Our study underscores the adaptive immune tolerance mechanisms and establishment of immunological balance during the first two trimesters following maternal SARS-CoV-2 infection.

中文翻译：

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妊娠早期母体 SARS-CoV-2 感染的母胎界面的免疫再平衡。


当前由严重急性呼吸综合征冠状病毒（SARS-CoV-2）引起的 2019 年冠状病毒病（COVID-19）大流行仍然对孕妇构成威胁。然而，妊娠早期 SARS-CoV-2 感染对母胎界面的影响仍知之甚少。在这里，我们对妊娠早期感染 SARS-CoV-2 的胎盘样本的单细胞转录组学和代谢组学进行了全面分析。与对照胎盘相比，SARS-CoV-2 感染在母胎界面引发免疫反应，并在感染后最初几周内诱导氨基酸和磷脂谱的代谢改变。然而，随后的免疫细胞激活和滋养层细胞免疫耐受的增强建立了一种新的动态平衡，减轻了对母胎界面的影响。值得注意的是，母胎界面的免疫反应和代谢变化在妊娠中期表现出逐渐下降。我们的研究强调了母体 SARS-CoV-2 感染后前两个三个月的适应性免疫耐受机制和免疫平衡的建立。