Autoantigens, /3-cell specific

Autoantigen-specific CD8+ T cells may mediate autoimmune injury in the CNS [215], and cytotoxic T lymphocytes can attack and injure neurons [208, 210, 216, 217]. In a study of the effects of T cells specific for the onconeural antigen PNMA1 of the Ma family, transfer of CD4+ T cells to rats resulted in a perivascular inflammatory response that involved CNS regions affected... 

Structures expressed in the organs of an individual against his own immune system can mount an immune response. Autoantigens can be organ specific (e.g. insulin) or present in all cells (e.g. DNA). 

Are T Cells Involved in Specific Immune Responses to Autoantigens in Atopic Dermatitis Autoimmune phenomena to human self-proteins may also contribute to the pathophysiology of atopic dermatitis. IgE against autoantigens such as Horn SI-4 have been shown to stimulate type 1 hypersensitivity reactions which in turn may contribute to the clinical cutaneous reactions in atopic dermatitis [15]. Autoallergens induce the proliferation of CLA+ autoreactive T cells derived... 

Zhang, Y., LeRoy, G., Seelig, H.P., Lane, W.S., and Reinberg, D. (1998) The dermatomyositis-specific autoantigen Mi-2 is a component of a complex containing histone deacetylase and nucleosome remodeling activities. Cell 95, 279-289. 

Viruses can induce apoptosis of human keratinocytes. These apoptotic cells can express viral antigens and autoantigens, which are coclustered in specific subsets within surface blebs and then cause challenge to self-tolerance if not cleared and processed properly (R15). Andreassen et al. showed that T cell lines specific for polyomavirus T antigen recognize T antigen complexed with nucleosomes and trigger B cells to produce anti-DNA antibodies (A20). 

Fridkis-Hareli, M., Santambrogio, L., Stern, J.N., Fugger, L Brosnan, C., and Strominger, J.L. (2002) Novel synthetic amino acid copolymers that inhibit autoantigen-specific T cell responses and suppress experimental autoimmune encephalomyelitis. J. Clin. Invest. 109, 1635-1643. 

Refers to an idiotype where the idiotype is that portion of the variable region of an antibody that confers specificity. See Bigazzi, P.E., Regulation of autoimmunity and the idiotypic network, Immunol. Ser. 54, 39-64, 1991 Schoenfeld, Y, Idiotypic induction of autoimmunity do we need an autoantigen Clin. Exptl. Rheumatol. 12 (Suppl. 11), S37-S40, 1994 Schoenfeld, Y. and George, J., Induction of autoimmunity. A role for the idiotypic network, Ann. N.Y. Acad. ScL 815, 342-349, 1997 Bianchi, A. and Massaia, M., Idiotypic vaccination in B-cell malignancies. Mol. Med. Today 3, 435-441, 1997 Lacroix-Desmazes, S., Bayry, J., Misra, N. et al.. The concept of idiotypic vaccination against factor Vlll inhibitors in haemophilia A, Haemophilia 8 (Suppl. 2), 55-59, 2002 Coutinho, A., Will the idiotypic network help to solve natural tolerance Trends Immunol. 24, 53-54, 2003. 

Figure 3. Effects of heavy metals (Hg andAu) on Immune cells. Hg was described as able to interact with the nuclear antigen fibrillarin which was assumed to cause a T-cell response against this modified autoantigen. True autoreactive T-ceiis specific for the native antigen were detected in a second time. Hg was shown to induce the expression of a normally cryptic epitope of RNAse A leading to the activation of specific T-cells. However the relevance of this mechanism in terms of induction of autoimmunity has not been demonstrated. Hg orAu have also been shown to poiyctonaity activate T-cells mimicking the effects of stimulation with anti-TCR antibodies. This results in an increase in intracellular Ca concentration, MAP kinase activation and cytokine expression.

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