Objective:Mesenchymal stem cells( MSCs) have self-renewal capacity and potential to differentiate into the cells.It was reported that the expression of miR-30a changed in some immune diseases.But it remains unclear the effect of miR-30a on the im-munoregulatory functions of MSCs.Here we studied the impact of miR-30a on the phenotype,cell viability,apoptosis,cell cycle and im-munoregulatory functions of MSCs.Methods: The mixed enzyme methods were used for the isolation of human umbilical cord MSCs.Flow cytometry(FCM)was used to investigate the effect of overexpressed miR-30a on the phenotype of MSCs.CCK-8 was used to examine the cell viability of miR-30a-overexpressed MSCs.Annexin V/PI was used for the detection of apoptosis of MSCs.Q-PCR and Western blot were used to investigate the effect of miR-30a on the expression of Cyclin E2( CCNE2).CCNE2 was one putative target of miR-30a predicted by Targetscan database.The effects of miR-30a-overexpressed MSCs on the maturation of dendritic cells(DCs)were determined.Results:Overexpression of miR-30a blocked the cell cycle of MSCs in the G0/G1 phase by inhibiting the expression of CCNE2,but did not affect the phenotype, cell viability and apoptosis of MSCs.When co-cultured with DCs, although MSCs down-regulated the expression of CD40 and CD86 on DCs,overexpression of miR-30a more significantly enhanced the suppressive impact of MSCs on the maturation of DCs.Conclusion: miR-30a affects the cell cycle of MSCs and enhances its immunosuppressive effect on DCs.

Background and Objectives: The maternal-fetal interface is an important source of mesenchymal stem cells (MSCs), and it is influenced by high levels of estradiol (E2) during pregnancy. It is highly important to study the role of E2 in MSCs for both clinical application and understanding of the mechanisms underlying pregnancy related diseases. Methods: and Results: In this study, differently expressed genes (DEGs) were found in the MSCs after exposure to E2. Then, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of DEGs was performed and the integrated regulatory network of DEGs-miRNA was constructed. A total of 390 DEGs were found in the MSCs exposed to E2, including 164 upregulated DEGs (e.g. ADCY2, VEGFA and PPY) and 226 downregulated DEGs (e.g. KNG1, AGT and NPY). Additionally, 10 miRNAs (such as miR-148A/B, miR-152, miR-182) identified the integrated regulatory network of DEGs-miRNAs. Among them, the expression of ADCY2 was significantly upregulated, and this was associated with multiple changed genes. We confirmed that the expression of ADCY2 is significantly promoted by E2 and subsequently promoted the production of cAMP in MSCs. We also found that E2 promoted ADCY2 expression by inhibiting miR-152 and miR-148a. Conclusions E2 promotes the expression of cAMP through miR-148a/152-ADCY2 in MSCs. It is suggested that E2 plays a key role in the growth and function of MSCs.