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

Background: Current biomarkers for early detection of sepsis have low sensitivity and specificity. Serum microRNAs (miRNAs) have been proposed as novel non-invasive 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 profile was performed using peripheral blood from three sepsis patients in sepsis stage and condition improved stage using microarray screening. The differentially expressed miRNAs were primary validated by real-time quantitative polymerase chain reaction (qRT-PCR) in a further set of 20 sepsis patients in the sepsis stage and condition improved stage. We finally validate the different expressed miRNA in 95 sepsis patients and 66 non sepsis patients. The validated miRNAs along with patients’ clinical indictors were analyzed in a multivariate logistic regression model. The diagnosis value of the changed miRNA in sepsis was determined and compared with CRP and WBC by analyzing the receiver operating characteristic (ROC) curves. Results: : According to the criteria we detected 11 miRNAs regulated by miRNA chip. qRT-PCR detection showed that the expression of hsa-let-7d-3p in sepsis patient was up regulated compared with non-sepsis patients. In a multiple logistic regression analysis, serum miRNA hsa-let-7d-3p was found to be independent predictor of sepsis. Receiver operating characteristic curve (ROC) analysis showed that the area under ROC curve of serum miRNA hsa-let-7d-3p was 0.696 (95% confidence interval [0.615, 0.778]). Conclusion: miRNA hsa-let-7d-3p was identified as novel biomarkers for the early detection of sepsis.