Novel miRNA biomarkers for alveolar echinococcosis: sequencing and clinical validation

This study aimed to explore extracellular microRNA derived from <i>Echinococcus multilocularis</i> (EM) in the plasma of patients with alveolar echinococcosis (AE) and assess its potential as a diagnostic biomarker. EM-derived miRNAs were identified in plasma samples from 20 AE patients through miRNA sequencing. Three novel miRNA molecules (emu-miR-novel 1, 2 and 3) were predicted through bioinformatic analysis to elucidate their chromosomal locations, secondary structures and precursor forms. Subsequently, plasma samples from 30 AE patients and 30 controls were utilized to establish an assay <i>via</i> stem-loop reverse transcription PCR, optimizing primers, reaction systems, and conditions to assess cross-reactivity and sensitivity. Clinical validation revealed that emu-miR-novel 1 had the highest diagnostic accuracy, with an area under the curve (AUC) of 0.8994, a <i>P</i> value of less than 0.0001, a sensitivity of 83.3%, and a specificity of 86.7%. Statistically significant differences were observed between the groups for emu-miR-novel 1 (<i>P</i> < 0.05), whereas emu-miR-novel 2 and 3 showed AUC values of 0.7922 and 0.6883, with <i>P</i> values of 0.0001 and 0.012, respectively, indicating no significant difference between groups (<i>P</i> > 0.05). Furthermore, the assay showed no cross-reactivity with samples from 18 common viruses, 4 parasitic infections, and miRNAs from AE sequenced from 8 species, confirming its high specificity. Emu-miR-novel 1 exhibited a sensitivity of 1 femtomolar. Emu-miR-novel 1 holds promise as a key diagnostic tool for AE, offering a novel perspective and approach for disease diagnosis.