TNF and osteoarthritis: Cytokines have been detected in exosomes that were recovered from synovial fluid of patients with osteoarthritis (IL-1β, IL-2, IL-4, IL-5, IL-6, IL-13, IL-17, TNF-α, and IFN-γ), plasma from alcohol and cigarette-consuming human immunodeficiency virus (HIV)-positive patients (IL-8 and IL-10), in EVs that were recovered from diabetes mellitus patients (TNF-α), as well as in culture medium of HIV-infected macrophages that were stimulated with cigarette components (IL-6) [12,13,14,15].