Autoimmunity

Definition

Autoimmunity is a condition where the immune system mistakenly attacks the body's own cells, tissues, and organs. It involves an inappropriate response by adaptive immunity, particularly B lymphocytes and T lymphocytes.

5 Must Know Facts For Your Next Test

1. Autoimmune diseases can result from the failure of self-tolerance mechanisms in B lymphocytes.
2. Molecular mimicry, where foreign antigens resemble self-antigens, can trigger autoimmunity.
3. Autoantibodies produced by B cells are hallmark indicators of many autoimmune diseases.
4. Regulatory T cells (Tregs) play a crucial role in preventing autoimmunity by maintaining immune tolerance.
5. Examples of autoimmune diseases include systemic lupus erythematosus (SLE) and rheumatoid arthritis.

Review Questions

• What role do B lymphocytes play in autoimmunity?
• How does molecular mimicry contribute to the onset of autoimmune diseases?
• Why are regulatory T cells important in preventing autoimmunity?

Related terms

B lymphocyte:

A type of white blood cell involved in producing antibodies as part of the humoral immune response.

Self-tolerance: The ability of the immune system to recognize self-produced antigens as non-threatening.

Regulatory T cell (Treg): A subset of T cells that modulate the immune system and prevent autoimmune disease by maintaining tolerance to self-antigens.