LAUSR

HighlightsPlasma‐derived exosomes carried mtDNA.Exosomes contribute to inflammation through the mtDNA‐TLR9‐NF‐&kgr;B pathway.Chloroquine can block this pathway. Abstract Exosomes are small vesicles that contain proteins, DNA and RNA, and play an important role in inflammation; however, the underlying mechanism remains unclear. In the present study, we found increased plasma‐derived exosomes in chronic heart failure patients compared with healthy controls. Further, our data demonstrated that plasma‐derived exosomes carried mtDNA, and triggered an inflammatory response via the TLR9‐NF‐&kgr;B pathway, as well, the inflammatory effect was closely related to exosomal mtDNA copy number. However, the effect could be blocked by chloroquine (CQ), a TLR9 inhibitor. These findings reveal a new mechanism of exosome‐induced inflammation, and provide a new perspective for intervention and treatment of inflammation‐related diseases, such as chronic heart failure.