Evidence for the circulating microRNA hsa-let-7d-3p as a potential new biomarker for sepsis in human subjects

Abstract

Abstract Background Current biomarkers for the early detection of sepsis have low sensitivity and specificity. Serum microRNAs (miRNAs) have been proposed as novel noninvasive biomarkers for various diseases. The aim of the present study was to discover a novel diagnostic biomarker for sepsis in human subjects. Methods miRNA expression profiling was performed using peripheral blood from three sepsis patients in the sepsis stage and improved condition stage using microarray screening. The differentially expressed miRNAs were primary validated by real-time quantitative polymerase chain reaction (RT-qPCR) in a further set of 20 sepsis patients in the sepsis stage and improved condition stage. Finally, we validated the differentially expressed miRNAs in 95 sepsis patients and 66 nonsepsis patients. The validated miRNAs and patients’ clinical indictors were analysed in a multivariate logistic regression model. The diagnostic value of the changed miRNA in sepsis was determined and compared with CRP and WBC by analysing the receiver operating characteristic (ROC) curves. Results According to the criteria, we detected 11 miRNAs regulated by the miRNA chip. RT-qPCR detection showed that the expression of hsa-let-7d-3p in sepsis patients was upregulated compared with that in nonsepsis patients. In a multiple logistic regression analysis, serum miRNA hsa-let-7d-3p was found to be an independent predictor of sepsis. Receiver operating characteristic curve (ROC) analysis showed that the area under the ROC curve of serum hsa-let-7d-3p was 0.696 [95% confidence interval (0.615, 0.778)]. Conclusion The miRNA hsa-let-7d-3p was identified as a novel biomarker for the early detection of sepsis.