T cell autoimmunity to histones and nucleosomes is a latent property of the normal immune system.
Arthritis Rheum
; 46(5): 1270-81, 2002 May.
Article
em En
| MEDLINE
| ID: mdl-12115233
ABSTRACT
OBJECTIVE:
Investigators in this study undertook to determine whether in vitro antigen-responsive immune (polyomavirus T antigen [T-ag]- specific) and autoimmune (histone-specific) T cells from normal individuals share structural and genetic characteristics with those from patients with systemic lupus erythematosus (SLE).METHODS:
Histone-specific T cells were generated by stimulation of peripheral blood mononuclear cells (PBMCs) with nucleosome-T-ag complexes and were subsequently maintained by pure histones. T-ag-specific T cell clones were initiated and maintained by T-ag. The frequencies of circulating histone- and T-ag-specific T cells were determined in healthy individuals and in SLE patients by limiting dilution of PBMCs. T cell receptor (TCR) gene usage and variable-region structures were determined by complementary DNA sequencing. These sequences were compared between T-ag- and histone-specific T cells and between normal individuals and SLE patients for each specificity.RESULTS:
Individual in vitro-expanded histone- and T-ag-specific T cells from normal individuals displayed identical TCR V(alpha) and/or V(beta) chain third complementarity-determining region (CDR3) sequences, indicating that they were clonally expanded in vivo. The frequencies of in vitro antigen-responsive T-ag- or histone-specific T cells from normal individuals were similar to those from SLE patients. Although heterogeneous for variable-region structure and gene usage, histone-specific T cells from healthy individuals and SLE patients selected aspartic and/or glutamic acids at positions 99 and/or 100 of the V(beta) CDR3 sequence.CONCLUSION:
Autoimmune T cells from healthy individuals can be activated by nucleosome- T-ag complexes and maintained by histones in vitro. Such T cells possessed TCR structures similar to those from SLE patients, demonstrating that T cell autoimmunity to nucleosomes may be a latent property of the normal immune system.
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Bases de dados:
MEDLINE
Assunto principal:
Histonas
/
Nucleossomos
/
Linfócitos T
/
Autoimunidade
/
Sistema Imunitário
Limite:
Adult
/
Female
/
Humans
/
Middle aged
Idioma:
En
Revista:
Arthritis Rheum
Ano de publicação:
2002
Tipo de documento:
Article
País de afiliação:
Noruega