This study investigated the role of Echinococcus multilocularis vesicle-derived extracellular vesicles(EVs)con-taining emu-miR-10-5p in regulating HSC activation in vitro.Mice were injected intraperitoneally with protoscoleces to con-struct a secondary alveolar echinococcosis model,and E.multilocularis vesicles were cultured in mice and identified by PCR.The EV structure in cultured vesicle tissue was observed by transmission electron microscopy.EVs were isolated from vesicle culture supernatants through differential-ultracentrifugation,and identified by transmission electron microscopy,nanoparticle size analysis,and western blotting.The activity of HSCs treated with different EV concentrations was detected with CCK-8 assays.The expression levels of α-SMA,and collagen Ⅰ and Ⅲ were detected by RT-qPCR and western blotting after EV treatment of HSCs.Bioinformatics analysis identified the specific miRNA emu-miR-10-5p.The proliferation of HSCs was detected with EdU after overexpression of emu-miR-10-5p,and the expression levels of α-SMA,collagen Ⅰ,and collagen Ⅲ in cells were detected by RT-qPCR and western blotting.Detection of α-SMA,collagen Ⅰ,and collagen Ⅲ expression levels in HSCs was performed after EVs were extracted from the culture supernatant of vesicular tissues with emu-miR-10-5p knockdown.E.multilocularis vesicles were successfully cultured from focal material in mice,and the E.multilocularis origin was confirmed through PCR amplification of specific genes.TEM observation of culture vesicles in-dicated abundant surface vesicular structures.E.multilocularis vesicle-derived EVs were isolated by differential-ultracentrifu-gation,and confirmed by TEM to be spherical and membrane like-structures.Vesicle-derived EVs were internalized by HSCs,and promoted the proliferation and activation of HSCs.Comprehensive analysis of miRNA sequencing results revealed emu-miR-10-5p expression in E.multilocularis-infected mouse serum,metacestode tissue,E.multilocularis-derived EVs,germi-nal layer cells,and protoscoleces.Moreover emu-miR-10-5p was confirmed to be present in higher amounts in E.multilocu-laris-derived EVs,according to RT-qPCR.Further studies confirmed that overexpression of emu-miR-10-5p promoted HSC proliferation and increased α-SMA,collagen Ⅰ,and collagen Ⅲ mRNA and protein expression levels in HSCs.In contrast,EVs extracted from culture supernatants after emu-miR-10-5p knockdown in vesicles did not increase a-SMA,collagen Ⅰ,and colla-gen Ⅲ mRNA and protein expression levels.E.multilocularis vesicle-derived EVs and emu-miR-10-5p thus promote the acti-vation of HSCs.