Figure 5.

How xenobiotics can induce autoimmunity. (1) Amplified innate immunity. Tissue damage caused by xenobiotics can lead to the presence of cellular components and other damage-associated molecular pattern molecules (DAMPs) or pathogen-associated molecular pattern molecules (PAMPs). It can also lead to the release of self- and modified self-antigens, the presentation of these self-antigens to nontolerant lymphocytes, and the induction of inflammation. (2) Amplified adaptive immunity. The effects already described lead to the engagement of toll-like receptors (TLRs) and other innate sensors, the production of proinflammatory cytokines, a decrease in Treg populations, an increase in autoreactive T- and B-cell populations, and the production of autoantibodies against various self-tissues, which can contribute to autoimmune diseases. IFN = interferon; TNF = tumor necrosis factor; IL = interleukin; Treg = regulatory T cell; Teff = effector T cell.