TNF and systemic lupus erythematosus: Lee et al. (89) showed that circulating exosomes from patients with SLE induced a higher production of IFN-α, TNF-α, IL-1β, and IL-6 than exosomes from healthy individuals and that exosome levels correlated with disease activity in SLE patients, whereas depleted SLE serum and mechanically fragmented SLE exosomes both did not induce the production of any significant cytokines (89).