Kimura et al. showed that induction of human IFN-γ−IL-17A−FOXP3+CD4+ T cells is inhibited in the presence of patient (compared with healthy) blood exosomes, and that the exosomal miRNA profile of patients is characterized by significantly higher level of let-7i, able to target insulin like growth factor 1 receptor (IGF1R) and TGFBR1 in naïve Th cells (upon up-take of let-7i containing exosomes) and suppress induction of Treg cells, thus fueling MS pathogenesis (93). This evidence concerns the gene IGF1R and myeloid sarcoma.