目的 筛选细粒棘球蚴感染后绵羊血清中差异表达的miRNA，评价其在棘球蚴病诊断中的潜在价值。 方法 10只绵羊分为感染组（5只）和对照组（5只），感染组每只绵羊灌胃2 000个细粒棘球绦虫虫卵，对照组绵羊给予生理盐水。感染后60 d，收集两组绵羊外周血，提取血清总RNA，利用小RNA高通量测序鉴定并筛选差异表达的miRNA。选取5个差异表达miRNA进行实时荧光定量逆转录PCR（qRT-PCR）验证，并采用Medcale软件绘制受试者工作特征（ROC）曲线，计算曲线下面积（AUC），筛选具有潜在诊断价值（AUC ≥ 0.7）的miRNA。采用qRT-PCR检测15份细粒棘球蚴感染绵羊血清样品中具有潜在诊断价值的miRNA的转录水平，并计算曲线下面积（AUC）以及敏感性和特异性。采用miRanda和RNAhybrid软件对差异表达miRNA的靶基因进行预测，并进行基因本体（GO）富集分析和京都基因与基因组百科全书（KEGG）路径富集分析。 结果 测序结果显示，共鉴定出26个差异性表达的miRNAs，其中21个上调表达，5个下调表达。qRT-PCR结果显示，感染组oar-miR-191、oar-let-7a、oar-miR-150、oar-miR-26a、oar-miR-21等5个相对丰度较高的差异miRNA的相对表达水平分别为2.22 ± 0.31、2.12 ± 0.24、2.42 ± 0.35、2.09 ± 0.15、3.23 ± 0.83，均高于对照组（1.00 ± 0.11），其中oar-miR-191、oar-let-7a、oar-miR-150、oar-miR-26a的相对表达水平与对照组差异有统计学意义（t = 3.960、4.766、4.096、9.126，均P < 0.05）。ROC曲线分析发现，oar-let-7a、oar-miR-26a、oar-miR-21的AUC均小于0.7。oar-miR-191的AUC为0.858（95% CI为0.719~0.997，P < 0.05），具有较高的诊断价值，其灵敏度为71.43%，特异性为85.71%；oar-miR-150的AUC为0.738（95% CI为0.550~0.926，P < 0.05），具有一定的诊断意义，其灵敏度为53.33%，特异性为86.67%。GO显著性富集分析结果显示，转录水平上升两倍以上的miRNA靶基因主要与应激反应、细胞表面分子、蛋白质结合等功能相关；KEGG通路富集分析结果表明，转录水平上升至少两倍的miRNA靶基因主要富集在炎症反应、细胞自噬和细胞凋亡等关键信号通路上。 结论 本研究筛选出oar-miR-191和oar-miR-150在细粒棘球蚴感染诊断中具有较好的灵敏度和特异性，有望成为细粒棘球病诊断的潜在生物标志物。

Objective To screen the miRNAs differential expression profiles in the serum from the sheep infected with Echinococcus granulosus and evaluate their potential values in the diagnosis of echinococcosis. Methods 10 sheep were divided into an infection group (5) and a control group (5). The E. granulosus infected-group was given 2 000 eggs per sheep by gavage, and the control group of sheep was given saline. Sixty days after infection, peripheral blood was collected from both groups, and total serum RNA was extracted. Small RNA high-throughput sequencing was used to identify and screen differentially expressed miRNAs. Five differentially expressed miRNAs were validated by real-time quantitative PCR (qRT-PCR). MedCale software was used to draw receiver operating characteristic (ROC) curves, calculate the area under the curve (AUC), and select miRNAs with potential diagnostic values (AUC ≥ 0.7). qRT-PCR was used to detect the relative transcription levels of miRNAs with potential diagnostic values in 15 serum samples of sheep infected with E. granulosus, and the AUC, sensitivity, and specificity were calculated.Target genes of the differentially expressed miRNAs were predicted using miRanda and RNA hybrid software, and gene ontology (GO) enrichment analysis and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis were conducted. Results Sequencing results identified a total of 26 differentially expressed miRNAs, including 21 upregulated and 5 downregulated. The qRT-PCR results showed that the relative expression levels of five relatively abundant differentially expressed miRNAs in infection group, including oar-miR-191, oar-let-7a, oar-miR-150, oar-miR-26a, and oar-miR-21, were 2.22 ± 0.31, 2.12 ± 0.24, 2.42 ± 0.35, 2.09 ± 0.15, and 3.23 ± 0.83, respectively, which were higher than the control group (1.00 ± 0.11). There was a statistically significant difference in the relative expression levels of oar-miR-191, oar-let-7a, oar-miR-150, and oar-miR-26a compared to the control group (t = 3.960, 4.766, 4.096, 9.126; all P < 0.05). ROC curve analysis revealed that the AUC of oar-let-7a, oar-miR-26a, and oar-miR-21 were all less than 0.7. the AUC of oar-miR-191 was 0.858, with a 95% confidence interval (95% CI) of 0.719-0.997 (P < 0.05), indicating its high diagnostic value, with a sensitivity of 71.43% and specificity of 85.71%. The AUC of oar-miR-150 was 0.738, with a 95% CI of 0.550-0.926 (P < 0.05), indicating its diagnostic significance, with a sensitivity of 53.33% and specificity of 86.67%. The results of the GO significance enrichment analysis showed that miRNA target genes with transcriptional levels increased by more than twice were mainly related to stress response, cell surface molecules, protein binding, and other functions. The KEGG pathway enrichment analysis results indicate that miRNA target genes with at least a two-fold increase in transcription levels are mainly enriched in key signalling pathways such as inflammation response, autophagy, and apoptosis. Conclusion The oar-miR-191 and oar-miR-150 screened in this study have good sensitivity and specificity in the diagnosis of E. granulosus infection, suggesting their potential as a biomarker for the diagnosis of echinococcosis.