Profiling changes in microRNAs of immature dendritic cells differentiated from human monocytes.

MicroRNAs (miRNAs) critically impact a wide array of eukaryotic developmental and physiologic processes through post-transcriptional gene silencing. In this study, we employed miRNA array and investigated in vitro the miRNA profile of immature dendritic cells (iDCs) derived from monocytes isolated from human venous blood. Our results showed that there were 379 miRNAs which were detectable in both monocytes and iDCs among the 856 miRNAs assayed, of which 155 miRNAs were detectable in monocytes while 224 miRNAs were detectable in iDCs. There were 103 miRNAs differentially expressed which could be relevant to the differentiation of iDCs from human monocytes. Sixty-two out of 103 miRNAs were upregulated whereas 41 miRNAs were downregulated. Of particular interest were the tremendous upregulation of miR122a and the downregulation of miR200c in iDCs. In addition, it was found that the strikingly downregulated miRNAs in iDCs also included miR-335, miR-514, miR-509, miR-31, miR-442b, miR-1, miR-199a, miR-203, miR-363 and miR-489 whereas the upregulation of miR-210, miR-155, miR-126, miR-139, miR-452, miR-19a, miR-25 and miR-181d were remarkable. Our results revealed a profile change of miRNAs when human iDCs were differentiated from monocytes as a result of in vitro stimulation with relevant cytokines.