3.1 autoimmunity Flashcards
what is autoimmunity?
immune response against the host due to the loss of immunological tolerance of self antigens
what is an autoimmune disease?
disease caused by tissue damage or disturbed physiological responses due to an auto-immune response
what is the difference between an organ specific and non organ specific autoimmune disease?
organ specific - one or multiple self antigens within one single organ or tissue
e.g graves disease, goodpastures disease, multiple sclerosis, myasthenia gravis, pernicious anaemia
non organ specific - wide distributed self antigens throughout the body
e.g autoimmune haemolytic anaemia, rheumatoid arthritis, lupus
what is an autoantibody driven hypersensitivity reaction?
complement activation
antibody mediated cell cytotoxicity
neutrophil activation
what is an autoreactive T cell driven reaction?
cytotoxic T cells
macrophages
what are the criteria for the diagnosis of a disease as autoimmune?
1) presence of autoantibodies/autoreactive t cells
2) levels of autoantibodies correlate with disease severity
3) autoantibodies/autoreactive T cells found at the site of tissue damage
4) transfer of autoantibody or autoreactive t cells to a healthy host induces the autoimmune disease
5) clinical benefit provided by immunomodulatory therapy
6) family history
what are some mechanisms of induction of autoimmunity (potentially leading to an autoimmune disease)?
- breakdown of central tolerance (cant delete autoreactive t cells)
- breakdown of peripheral tolerance (t cell defects and impaired immunomodulation, altered self antigens)
- activation of autoreactive B cells
- genetic factors e,g affected sibling or twin
- environmental factors e.g hormones, infections, drugs
what current and future therapeutic strategies are used for autoimmune disease?
- plasma exchange
- immunosuppresive drugs
- anti-inflammatory drugs
- replacement therapy surgery
