More MS news articles for July 2004

Adaptive Immunity: Histocompatibility Antigens and Immune Response Genes

Disease and the Major Histocompatibility Complex

http://www.medscape.com/viewarticle/482335?src=search

July 12, 2004
Edgar L. Milford, MD; Charles B. Carpenter, MD, Harvard Medical School
ACP Medicine

Many diseases have been associated with certain major histocompatibility complex (MHC) antigens. Such associations per se show only that the MHC molecules or some other genes closely linked in the human leukocyte antigen (HLA) region have an influence on initiation or expression of disease. A relative risk of 5, for example, means only that there is a fivefold increase in the likelihood of disease in a person with a particular HLA antigen, compared with someone who does not have that antigen. It indicates nothing about the frequency of the disease itself, which may be rare or common. One explanation for such associations is that the disease in question is related to a deficiency in the immune response to a particular causative organism. There is increasing evidence, however, that organ-specific HLA-associated diseases -- such as type 1 diabetes mellitus, multiple sclerosis, Graves disease, the glomerulonephritides, celiac disease, ankylosing spondylitis, and rheumatoid arthritis -- have a major component of autoimmunity.