Abstract
BACKGROUND: Recurrent pregnancy loss (RPL), characterized by multiple miscarriages, remains a condition with unclear etiology, posing significant challenges for affected women and couples. This study aims to explore the underlying mechanisms of RPL, focusing on the role of decidual Natural Killer (dNK) cells and the TNF receptor-associated factor 3 (TRAF3) gene as a potential diagnostic marker and therapeutic target. METHODS: We used single-cell transcriptomic analysis and machine learning techniques to analyze decidual tissues from RPL patients and normal pregnancy(NP). Weighted Gene Co-expression Network Analysis (WGCNA) was employed to identify key gene clusters. Validation studies included RT-PCR, immunohistochemistry, and molecular docking analyses. RESULTS: We observed an increased proportion of specific dNK cell subtypes (dNK2 and dNK3) in the RPL group compared to NP, implicating their role in RPL pathology. dNK cells in RPL primarily interacted with monocytes via the Macrophage Migration Inhibitory Factor (MIF) signaling pathway. Our diagnostic model, incorporating TRAF3 and nine other genes, demonstrated high diagnostic efficiency. TRAF3 expression was significantly lower in the decidua of RPL patients, and Diethylstilbestrol and Metformin were identified as potential modulators of TRAF3. CONCLUSIONS: This study highlights TRAF3 as a promising diagnostic marker and therapeutic target for RPL. The diagnostic model we developed has potential for early detection and personalized treatment strategies for RPL.