Autoimmunity: When the Immune System Attacks the Body It Was Built to Protect Autoimmune disease — a category encompassing over 80 distinct conditions in which the immune system generates antibodies and T-cell responses directed against the body's own tissues — now affects an estimated 4 million people in the UK, with incidence increasing at a rate that cannot be explained by genetic factors alone and demands an environmental explanation. The primary mechanisms by which environmental triggers convert a healthy immune system to an autoimmune one include molecular mimicry (where immune responses to microbial antigens cross-react with structurally similar self-proteins), bystander activation (where inflammation in one tissue non-specifically activates autoreactive lymphocytes), and epitope spreading (where tissue damage releases novel self-antigens that prime new autoreactive responses) — all of which are initiated and perpetuated by environmental toxins, chronic infections, gut permeability, and the adjuvant-like effects of heavy metals and other xenobiotics. The three-hit hypothesis — requiring genetic susceptibility, environmental trigger, and loss of tolerance — explains why autoimmunity cannot be reduced to genetics and why the environmental piece is both the cause and the therapeutic target.
#autoimmunity #molecular mimicry
