[Study on mechanisms of Th17/Treg imbalance in patients with cystic echinococcosis based on miRNA expression profiles].

ABSTRACT

OBJECTIVE: To investigate the serum microRNA (miRNA) expression and examine the impact of miRNA expression profiles on T helper type 17 (Th17)/regulatory T cells (Treg) imbalance among patients with cystic echinococcosis, so as to provide insights into the illustration of the mechanisms underlying chronic Echinococcus granulosus infections, and long-term pathogenesis. METHODS: Total RNA was extracted from the sera of cystic echinococcosis patients and healthy controls, and subjected to high-throughput sequencing with the Illumina sequencing platform. Known miRNAs were annotated and new miRNAs were predicted using the miRBase database and the miRDeep2 tool, and differentially expressed miRNAs were identified. The target genes of differentially expressed miRNAs were predicted using the software miRanda and TargetScan, and the intersection was selected for Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Among the differentially expressed miRNAs with the 20 highest fold changes, miRNAs that targeted genes relating to key transcription factors RORC and FOXP3 that determine the production of Th17 and Treg cells or their important regulatory pathways (PI3K-Akt and mTOR pathways) were matched. RESULTS: A total of 53 differentially expressed miRNAs were screened in sera of cystic echinococcosis patients and healthy controls, including 47 up-regulated miRNAs and 6 down-regulated miRNAs. GO enrichment analysis showed that these differentially expressed miRNA were involved DNA transcription and translation, cell components, cell morphology, neurodevelopment and metabolic decomposition, and KEGG pathway analysis showed that the differentially expressed miRNA were mainly involved in MAPK, PI3K-Akt and mTOR signaling pathways. Among the differentially expressed miRNAs with the 20 highest fold changes, there were 3 miRNAs that had a potential for target regulation of RORC, and 15 miRNAs that had a potential to target the PI3K-Akt and mTOR signaling pathways. CONCLUSIONS: Significant changes are found in serum miRNA expression profiles among patients with E. granulosus infections, and differentially expressed miRNAs may lead to Th17/Treg imbalance through targeting the key transcription factors of Th17/Treg or PI3K-Akt and mTOR pathways, which facilitates the long-term parasitism of E. granulosus in hosts and causes a chronic disease.