AUTHOR=Ni Fen-fen , Liu Guang-lei , Jia Shi-lei , Chen Ran-ran , Liu Li-bing , Li Cheng-rong , Yang Jun , Gao Xiao-Jie 

TITLE=Function of miR-24 and miR-27 in Pediatric Patients With Idiopathic Nephrotic Syndrome

JOURNAL=Frontiers in Pediatrics

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/pediatrics/articles/10.3389/fped.2021.651544

DOI=10.3389/fped.2021.651544

ISSN=2296-2360

ABSTRACT=<p><bold>Purpose:</bold> We investigated the pathogenesis of idiopathic nephrotic syndrome (INS) by measuring the effects two specific miRNAs on Th2 cells in children with this disease.</p><p><bold>Methods:</bold> After informed consent, we enrolled 20 children with active INS before steroid initiation, 20 children with INS in remission after steroid therapy, and 20 age-matched healthy controls. Flow cytometry was used to measure the levels of Th2 cells and a cytometric bead array was used to measure the levels of IgE, interleukin (IL)−4, and IL-13. RT-PCR was used to measure the levels of miR-24 and miR-27 in CD4<sup>+</sup>TCD25<sup>−</sup> cells. PBMCs were isolated using Ficoll density gradient centrifugation, and transfected with different mimic or inhibitor miRNAs. RT-PCR was used to measure the expression of different RNAs, and flow cytometry was used to determine the percentage of Th2 cells.</p><p><bold>Results:</bold> Relative to healthy controls, children with active INS had higher percentages of Th2 cells (<italic>P</italic> &lt; 0.05), but there was no significant difference in controls and children in remission. The plasma levels of IgE, IL-4, and IL-13 were significantly increased in children with active INS (<italic>P</italic> &lt; 0.05). There were lower levels of miR-24 and miR-27 in children with active non-atopic INS (<italic>P</italic> &lt; 0.05). Transfection experiments indicated that upregulation of each miRNA decreased the percentage of Th2 cells and the level of IL-4 (<italic>P</italic> &lt; 0.05), and down-regulation of each miRNA had the opposite effects (<italic>P</italic> &lt; 0.05).</p><p><bold>Conclusion:</bold> Children with active INS, with or without atopy, had higher levels of IgE, possibly related to their higher levels of IL-13 and IL-4 due to a drift toward Th2 cells. miR-24 and miR-27 suppressed the expression of Th2 cells and have a critical function regulating Th2 cell expression in INS.</p>