Aging of the immune system: a risk factor for autoimmunity?
Aging of the immune system, or immunosenescence, is characterized by changes in T cell subsets, cellular and molecular level alterations and thymic atrophy, resulting in a decline of T and B cell function. These alterations have been shown to be accompanied by a loss of ability to recognize "self" and "foreign" antigens. Therefore the development of autoimmune responses like production of autoantibodies has been hypothesized to be secondary to thymus involution with a decline of naïve T cells and accumulation of clonal T cells with activation due to "neoantigens" during the aging process. Altered apoptosis and altered T cell homeostasis have been emphasized to promote a chronic inflammatory state and lead to the concept of a immune-risk phenotype. However, it has to be proven which kinds of mechanisms turn the immune system to manifest autoimmune disease and how speculated defects in T cell differentiation and interaction leading to premature aging of the immune system may contribute to the development of autoimmune diseases.
Prelog
Martina
M
Department of Pediatrics, Medical University Innsbruck, Anichstr. 35 A-6020 Innsbruck, Austria. Martina.Prelog@uibk.ac.at
D000375:Aging / Q000276:immunology*; D000818:Animals; D001284:Atrophy / Q000276:immunology; D001327:Autoimmune Diseases / Q000209:etiology / Q000276:immunology*; D015551:Autoimmunity / Q000276:immunology*; D003586:Cytomegalovirus Infections / Q000150:complications; D006801:Humans; D007249:Inflammation / Q000150:complications; D008954:Models, Biological; D012307:Risk Factors; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013950:Thymus Gland / Q000473:pathology