introduction to immune disorders

Autoimmune diseases occur when the immune system, no longer recognising self-antigens found on the surface of the cells in the body, subsequently reacts against those cells. To date, over 70 types of autoimmune diseases have been identified and characterised, such as rheumatoid arthritis, multiple sclerosis and type I (insulin-dependent) diabetes mellitus[1]; 2-3% of the world population suffer from an autoimmune disease[2].

There has been recent interest in the Major Histocompatible Complex (MHC), a small region (6P21.3) found on the human chromosome 6 that is believed to be associated with all human autoimmune diseases[3]. It is now known that the MHC codes for Human Lymphocyte Antigens (HLA) classes I & II, and also a series of non-HLA related proteins that are especially relevant to autoimmune disease. The interactions of the MHC and the HLA proteins are crucial to the normal development and resultant function of the immune system.

Despite the wide variety of autoimmune diseases, discussing all of them is beyond the scope of this report. Instead, three immune disorders will receive special focus: rheumatoid arthritis (RA), insulin-dependent diabetes mellitus (IDDM), and autoimmune disease associated with HIV. While not exhaustive, these three diseases provide an excellent framework for the analysis of immune disorders that are particularly amenable to treatment via immunotherapy.



With Special Thanks to Ashley Michaella Burgess Robinson, David Anthony Leach, and Stephen Pomedli.

1) Report of the Autoimmune Diseases Coordinating Committee. October 2000. National Institutes of Health.
2) Philippa Marrack, John Kappler & Brian L. Kotzin. Autoimmune disease: why and where it occurs. Nature Medicine 2001, 7: 889-905.
3) Becker KG: Comparative Genetics of Type I Diabetes and Autoimmune Disease: Common loci, common pathways. Diabetes 1999, 48: 1353-1358.