Extracellular microRNA signature of human helper T cell subsets in health and autoimmunity [RNA]

Upon TCR stimulation, CD4+ T lymphocytes release extracellular vesicles (EVs) containing microRNAs. However, no data are available on whether human CD4+ T cell subsets release EVs containing different pattern of microRNAs. The present work aimed at filling this gap by assessing the microRNA content in EVs released upon in vitro TCR stimulation of Th1, Th17 and T regulatory (Treg) cells. Our results indicate that EVs released by Treg cells are significantly different compared to those released by the other subsets. In particular, miR-146a-5p, miR-150-5p and miR-21-5p are enriched; while miR-106a-5p, miR-155-5p and miR-19a-3p are depleted in Treg-derived EVs. The in vitro identified EV-associated microRNA signature was increased in serum of autoimmune patients with psoriasis and returned to healthy levels upon effective treatment with Etanercept, a biological drug targeting the TNF pathway and suppressing inflammation. Moreover, gene set enrichment analysis showed an over-representation of genes relevant for T cell activation, such as CD40L, IRAK1, IRAK2, STAT1 and c-Myb in the list of validated targets of Treg-derived EV miRNAs. At functional level, Treg- (but not Th1/Th17-) derived EVs inhibited CD4+ T cell proliferation and suppressed two relevant targets of miR-146a-5p, Stat1 and Irak2. In conclusion, our work identified the miRNAs specifically released by different human CD4+ T cell subsets and started to unveil the potential use of their quantity in human serum to mark the pathological elicitation of these cells in vivo and their biological effect in cell-to-cell communication during the adaptive immune response.

from #AlexandrosSfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2jG8Q8k
via IFTTT