Atosiban-conjugated 3WJ-pRNA nanoparticles delivering GAS1-enhanced extracellular vesicles: targeting the decidua to combat recurrent miscarriage

Background: Recurrent miscarriage (RM) remains a significant clinical challenge due to insufficient understanding of decidual microenvironment dysfunction and limited effective therapeutic options. Current treatments primarily focus on immunomodulation and hormonal therapy, which often fail to address the underlying decidual communication defects. This study investigates growth arrest-specific gene 1 (GAS1) as a potential therapeutic target for RM by elucidating its role in extracellular vesicle (EV)-mediated decidual communication and developing a novel RNA nanotechnology-based delivery system for targeted uterine treatment. Results: GAS1 is identified as a critical regulator of the biogenesis of EVs in decidual stromal cells (DSCs), and its deficiency is strongly associated with pregnancy-related pathologies. Mechanistic investigations suggest that GAS1 modulates RAB39B, a key regulator involved in EV biogenesis and transport, potentially contributing to decidual homeostasis. EVs derived from GAS1-overexpressing DSCs (GAS1-EVs) are enriched in GAS1 protein, forming a self-reinforcing loop for decidual support, while their reprogrammed cargo facilitates embryonic adhesion, trophoblast migration, and angiogenesis. The use of Atosiban-conjugated three-way junction-pRNA (3WJ-pRNA) for the targeted delivery of GAS1-enhanced EVs (Atosiban-GAS1-EVs) to the uterus in early pregnancy is explored, offering a promising non-invasive targeted treatment for women with RM. This targeted approach restores decidual microenvironment organization and reduces fetal resorption rates in murine RM models. Conclusions: This study unveils that the GAS1-RAB39B axis may play a significant role in EV-mediated decidual communication and provide a potential non-invasive, RNA nanotechnology-driven strategy for RM treatment.