CCL17 and autoimmune disease: Smoking tobacco can induce inflammatory and autoimmune diseases via genetic/epigenetic changes, increased oxidative stress, and free radical production, leading to enhanced proliferation of B and T cells, reduced regulatory T cell function, elevated pro-inflammatory cytokines (IL-1β, IL-6, IL-8, and tumor necrosis factors), increased expression of chemotactic cytokines such as recombinant human CXCL9 (MIG), thymus and activation-regulated chemokine, and interferon-inducible T cell α chemoattractant [26,27,28,29,30,31,32,33,34,35,36,37,38].