Dendritic cells (DCs) release exosomes with different characteristics based on stimulus. Here, we showed that DC cultures stimulated with low-level IFNγ (
gamma interferon and immune stimulator) released exosomes (IFNγ-DC-Exos) that contained
microRNA species that can increase baseline myelination, reduce oxidative stress, and improve remyelination following
chemical (lysolecithin)-induced demyelination. Furthermore, nasally administered IFNγ-DC-Exos increased CNS myelination in vivo. IFNγ-DC-Exos were preferentially taken up by oligodendrocytes, suggesting that they directly impact oligodendrocytes to increase myelination. Thus, our results show great potential for use of these IFNγ-DC-Exos as a therapeutic to promote remyelination in multiple sclerosis and dysmyelinating syndromes.