Human reproductive success relies on the proper differentiation of the uterine endometrium to facilitate implantation, formation of the placenta, and pregnancy. This process involves two critical types of decidual uterine cells: endometrial/decidual stromal cells (dS) and uterine/decidual natural killer (dNK) cells. To better understand the transcription factors governing the in vivo functions of these cells, we analyzed single-cell transcriptomics data from first-trimester terminations of pregnancy, and for the first time conducted gene regulatory network analysis of dS and dNK cell subpopulations. Our analysis revealed stromal cell populations that corresponded to previously described in vitro decidualized cells and senescent decidual cells. We discovered new decidualization driving transcription factors of stromal cells for early pregnancy, including DDIT3 and BRF2, which regulate oxidative stress protection. For dNK cells, we identified transcription factors involved in the immunotolerant (dNK1) subpopulation, including IRX3 and RELB, which repress the NFKB pathway. In contrast, for the less immunotolerant (dNK3) population we predicted TBX21 (T-bet) and IRF2-mediated upregulation of the interferon pathway. To determine the clinical relevance of our findings, we tested the overrepresentation of the predicted transcription factors target genes among cell type-specific regulated genes from pregnancy disorders, such as recurrent pregnancy loss and preeclampsia. We observed that the predicted decidualized stromal and dNK1-specific transcription factor target genes were enriched with the genes downregulated in pregnancy disorders, whereas the predicted dNK3-specific targets were enriched with genes upregulated in pregnancy disorders. Our findings emphasize the importance of stress tolerance pathways in stromal cell decidualization and immunotolerance promoting regulators in dNK differentiation.

人类生殖的成功依赖于子宫内膜的适当分化以促进着床、胎盘的形成和妊娠。这个过程涉及两种关键类型的子宫蜕膜细胞：子宫内膜/蜕膜基质细胞（dS）和子宫/蜕膜自然杀伤（dNK）细胞。为了更好地了解控制这些细胞体内功能的转录因子，我们分析了妊娠早期终止的单细胞转录组学数据，并首次对 dS 和 dNK 细胞亚群进行了基因调控网络分析。我们的分析揭示了与先前描述的体外蜕膜细胞和衰老蜕膜细胞相对应的基质细胞群。我们发现了新的蜕膜化驱动早孕基质细胞转录因子，包括调节氧化应激保护的 DDIT3 和 BRF2。对于 dNK 细胞，我们鉴定了参与免疫耐受 (dNK1) 亚群的转录因子，包括 IRX3 和 RELB，它们抑制 NFKB 通路。相反，对于免疫耐受较差 (dNK3) 的人群，我们预测 TBX21 (T-bet) 和 IRF2 介导的干扰素途径上调。为了确定我们的研究结果的临床相关性，我们测试了妊娠疾病（例如复发性流产和先兆子痫）的细胞类型特异性调节基因中预测的转录因子靶基因的过度表达。我们观察到，预测的蜕膜基质和 dNK1 特异性转录因子靶基因富含妊娠性疾病中下调的基因，而预测的 dNK3 特异性靶基因富含妊娠性疾病中上调的基因。 我们的研究结果强调了基质细胞蜕膜化中应激耐受途径和 dNK 分化中免疫耐受促进调节因子的重要性。