Identification of serum MicroRNAs as diagnostic biomarkers for influenza H7N9 infection

MicroRNAs (miRNAs) have been reported to play an important role in influenza virus-host interactions. To gain more insight into the contribution of miRNAs to the host immune response, the miRNA expression profiles in the sera of H7N9-infected patients and healthy controls were analyzed using miRNA microarray. Among the ninety-four miRNAs that were significantly differentially expressed in H7N9 serum samples when compared with that of healthy controls, fifty-three miRNAs were up-regulated and forty-one down-regulated. Five serum miRNA candidates (hsa-miR-197-5p, hsa-miR-320a, hsa-miR-320d, hsa-miR-320e, and hsa-miR-765) were further verified by RT-qPCR. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the potential use of these miRNAs for the H7N9 infection diagnosis from the serum samples. In silico analyses indicate that most the target genes of these miRNAs are implicated in cell invasion, inflammatory response and apoptosis. Our results indicate that these miRNA biomarkers from serum samples can be used for influenza diagnosis.