A dysregulation of cytokine networks has been suggested to be involved in the pathogenesis of unexplained pregnancy loss. Gut microbiota affects host immune response and induces an imbalance in cytokine levels. However, how gut microbial dysbiosis disturbs cellular immune function in miscarriage remains inconclusive. Here we report that IL-2, IL-17A, IL-17F, TNF-α, and IFN-γ are significantly increased in serum of miscarriage patients. Fecal microbiome analyses indicate that microbial diversity and the relative abundances of Prevotella_1, Prevotellaceae_UCG_003 and Selenomonas_1 are significantly reduced in the cases. Correlation analyses indicate that some microbe-associated metabolites are positively associated with changes in levels of Th1/Th17 cytokines in the miscarriage group. Moreover, we identify that imidazolepropionic acid and 1,4-methylimidazoleacetic acid are associated with subsequent recurrent miscarriage. Our study highlights the network among gut microbiota, fecal metabolites and Th1/Th17-mediated immune response in miscarriage patients and explores the potential predictive values of two fecal metabolites for recurrent miscarriages.

细胞因子网络失调被认为与不明原因流产的发病机制有关。肠道菌群影响宿主免疫反应并导致细胞因子水平失衡。然而，肠道微生物失调如何干扰流产中的细胞免疫功能仍无定论。在这里，我们报告流产患者血清中的 IL-2、IL-17A、IL-17F、TNF-α 和 IFN-γ 显着增加。粪便微生物组分析表明，Prevotella_1、Prevotellaceae_UCG_003和Selenomonas_1的微生物多样性和相对丰度例中明显减少。相关性分析表明，一些微生物相关代谢物与流产组 Th1/Th17 细胞因子水平的变化呈正相关。此外，我们发现咪唑丙酸和 1,4-甲基咪唑乙酸与随后的复发性流产有关。我们的研究强调了流产患者肠道微生物群、粪便代谢物和 Th1/Th17 介导的免疫反应之间的网络，并探讨了两种粪便代谢物对复发性流产的潜在预测价值。