Self-nonself discrimination by T cells
Article Abstract:
B cell antigen receptors are called immunoglobulins, or antibodies, and may exist in either soluble forms or as cell-surface receptors. In contrast, T cell antigen receptors exist only as cell surface molecules. In either case, the tremendous variety of antigen receptor molecules arises from random genetic recombination within the immune cells themselves; the repertoire of antigen reactivities is therefore created, not inherited. As a result of these random recombinatory events, some antigen receptors will react with foreign antigens and some will react with self antigens. How the immune system starts with this mixture and develops a set of cells specific for foreign antigens remains a major question for immunologists. In a review of the research on the development of T cells, the authors discuss how early T-cell maturation takes place through the interaction of molecules of the major histocompatibility complex, and the CD4 and CD8 cell surface antigens. Immature T cells that react with self antigen presented by the MHC molecules fail to thrive and may be deleted. T cells, which express both the CD4 and the CD8 antigen, might react with a Class I MHC molecule. If no self antigen is recognized, the T cell may go on to lose the CD4 receptor and become a "killer" or CD4-/CD8+ T cell. Conversely, if the same immature T cell reacted with a Class II molecule without reacting to self antigen, it might lose the CD8 receptor and mature into a "helper" or CD4+/CD8- T cell. (Consumer Summary produced by Reliance Medical Information, Inc.)
Publication Name: Science
Subject: Science and technology
ISSN: 0036-8075
Year: 1990
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GAD, a Single Autoantigen for Diabetes
Article Abstract:
Type I diabetes is an autoimmune disease caused by autoaggressive T cells. Researchers have made a breakthrough in understanding the causes of the disease. They have found that a single self protein expressed by [Beta]-islet cells, glutamic acid decarboxylase, controls its development in an animal model.
Publication Name: Science
Subject: Science and technology
ISSN: 0036-8075
Year: 1999
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Close-up of a killer: new atomic-scale images of the receptor of a killer T cell detail how the immune protein recognizes infected cells
Article Abstract:
A team led by Ian Wilson and Per Peterson have completed the detailed X-ray crystal structure of a T-cell receptor. The result will help understanding of how the receptor recognizes an infected cell, and may lead to insights into autoimmune diseases.
Publication Name: Science
Subject: Science and technology
ISSN: 0036-8075
Year: 1996
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