ENAGenomicsMolecular Immunology, MR, NIMRhttps://www.ebi.ac.uk/ena/browser/view/PRJNA259433Mus musculusxref:PubMed:25035954Foxp3+ regulatory T (Treg) cells prevent inflammatory disease but the mechanistic basis of suppression is not understood completely . Gene silencing by RNA interference can act in a cell-autonomous and non-cell-autonomous manner, providing mechanisms of inter-cellular regulation. Here, we demonstrate that non-cell-autonomous gene silencing, mediated by miRNA-containing exosomes, is a mechanism employed by Treg cells to suppress T cell-mediated disease. Treg cells transferred microRNAs (miRNA) to various immune cells, including T helper 1 (Th1) cells, suppressing Th1 cell proliferation and cytokine secretion. Use of Dicer-deficient or Rab27a and Rab27b double-deficient Treg cells to disrupt miRNA-biogenesis or the exosomal pathway, respectively, established a requirement for miRNAs and exosomes for Treg cell-mediated suppression. Transcriptional analysis and miRNA inhibitor studies showed that exosome-mediated transfer of Let-7d from Treg cell to Th1 cells contributed to suppression and prevention of systemic disease. These studies reveal a mechanism of Treg cell-mediated suppression mediated by miRNA-containing exosomes. Overall design: Regulatory T cells (CD4+CD25hiFoxp3rfp+, Treg) were isolated from naive mice. RNA as extracted form some Treg cells, while others were cultured in complete IMDM media for 3 days, stimulated with anti-CD3 anti-CD3 (1ug/ml) and anti-CD28 (10ug/ml). Exosomes were recovered from Treg cell supernatant, as described, and RNA was extracted form the purified exosomes. To identify which miRNAs were transferred to Dicer-deficient (KO) cells from Treg cells, we cultured Dicer KO cells alone, or co-cultured Dicer KO cells with Treg cells. RNA was extracted form Dicer KO cells cultured alone or from Dicer KO cells cultured in the presence of Treg cells. 3 x biological replicates were used. Each biological replicate was derived from a pool of 3-5 samples.ENAalpha-beta regulatory T-lymphocyte, suppressor T-cell, suppressor T cell., regulatory T lymphocyte, suppressor T-lymphocyte, Treg, suppressor T lymphocyte, alpha-beta regulatory T-cell, regulatory T-lymphocyte, alpha-beta regulatory T lymphocyte, CD4-positive, CD25-positive, regulatory T-cellMus musculus, Laboratory Mice., House, Mus, Laboratory, Swiss, Mus domesticus, mouse, Mus musculus domesticus, Swiss Mouse, mouse <Mus musculus>, Mouse, House Mice, Swiss Mice, house mouse, Mice, Laboratory Mouse, House Mouse, mice C57BL/6xCBA/CaJ hybrid, domesticus, Mus muscarisfalseMus musculusmiRNAs in Treg-derived Exosomes2025-09-242014-08-27PRJNA259433GSE606151009025035954