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Microbiology · Chapter 14

Autoimmunity: When Self-Tolerance Breaks

The immune system is built to attack invaders while sparing the body's own cells — a safeguard called self-tolerance. In autoimmune disease that safeguard fails, and the response turns inward. Tap each disease to see which self-tissue is attacked and how.

Pick a disease

tap a disease
Every autoimmune disease is one self-antigen the body stopped tolerating.
Autoimmune diseasestap one to explore
Self-toleranceLymphocytes that react against the body's own molecules are normally deleted or silenced — central tolerance in the thymus and bone marrow, backed by peripheral tolerance out in the tissues. Autoimmunity is what happens when that screening fails and self-reactive T cells or antibodies attack the body's own cells.
Self-tolerance: the thymus and bone marrow normally delete lymphocytes that react to “self.” Autoimmunity is that screening failing — friend gets mistaken for foe, and home tissue is attacked.