Exosomal LncRNA and CircRNA Regulate Peripheral Blood Mononuclear Cell Function through a Competitive Endogenous RNA Mechanism in Allergic Rhinitis.

Introduction: Peripheral blood mononuclear cells (PBMCs) dysfunction is involved in the pathogenesis and progression of allergic rhinitis (AR). This study aims to investigate the competing endogenous RNA (ceRNA) networks in PBMCs influenced by differentially expressed long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) found in plasma exosomes induced by AR.

Methods: All subjects were from the Affiliated Taizhou People's Hospital of Nanjing Medical University. Differential expression of messenger RNA (mRNAs) in PBMCs and lncRNAs/circRNAs in plasma exosomes was analyzed using high-throughput sequencing. Differentially expressed lncRNAs and circRNAs that target mRNAs were identified using bioinformatics methods. The predicted target mRNAs were intersected with the differentially expressed mRNAs in PBMCs to construct ceRNA networks. The subcellular localizations of lncRNAs and circRNAs within the ceRNA networks were determined using RNA fluorescence in situ hybridization or bioinformatics methods. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of differentially expressed mRNAs in PBMCs were conducted using the clusterProfiler R package. Quantitative reverse transcription polymerase chain reaction was used to validate the expression levels of each molecule within the constructed ceRNA networks in clinical samples, along with receiver operating characteristic (ROC) curve analysis to assess diagnostic value. Further validation was performed using in vitro cultured PBMCs and dual-luciferase reporter assays.

Results: Five differentially expressed circRNAs and 31 differentially expressed lncRNAs were identified in exosomes. In PBMCs, 130 differentially expressed mRNAs were identified. Six ceRNA networks were constructed, affecting PBMCs chemorepellent activity, JAK-STAT signaling pathway, and other functions or pathways. The expression level of ENST00000650850 in plasma exosomes was significantly lower in AR patients, suggesting its potential diagnostic value. The expression level of ENST00000650850 in plasma exosomes was positively correlated with the expression levels of ENST00000650850 and IL6 mRNA in PBMCs. PBMCs from healthy individuals were stimulated with plasma exosomes isolated from AR patients, leading to a reduction in IL6R mRNA expression levels in the PBMCs.

Conclusion: Differentially expressed lncRNA (ENST00000650850) in plasma-derived exosomes of AR patients may regulate IL6R mRNA expression in PBMCs via miR-6747-3p, thereby influencing PBMC function and contributing to the pathogenesis and progression of AR.