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The U1-snRNP complex: structural properties relating to autoimmune pathogenesis in rheumatic diseases.

ABSTRACT: The U1 small nuclear ribonucleoprotein particle (snRNP) is a target of autoreactive B cells and T cells in several rheumatic diseases including systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD). We propose that inherent structural properties of this autoantigen complex, including common RNA-binding motifs, B and T-cell epitopes, and a unique stimulatory RNA molecule, underlie its susceptibility as a target of the autoimmune response. Immune mechanisms that may contribute to overall U1-snRNP immunogenicity include epitope spreading through B and T-cell interactions, apoptosis-induced modifications, and toll-like receptor (TLR) activation through stimulation by U1-snRNA. We conclude that understanding the interactions between U1-snRNP and the immune system will provide insights into why certain patients develop anti-U1-snRNP autoimmunity, and more importantly how to effectively target therapies against this autoimmune response.

SUBMITTER: Kattah NH

PROVIDER: S-EPMC3074261 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature

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The U1-snRNP complex: structural properties relating to autoimmune pathogenesis in rheumatic diseases.

Kattah Nicole H NH Kattah Michael G MG Utz Paul J PJ

Immunological reviews 20100101 1

The U1 small nuclear ribonucleoprotein particle (snRNP) is a target of autoreactive B cells and T cells in several rheumatic diseases including systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD). We propose that inherent structural properties of this autoantigen complex, including common RNA-binding motifs, B and T-cell epitopes, and a unique stimulatory RNA molecule, underlie its susceptibility as a target of the autoimmune response. Immune mechanisms that may contrib ...[more]

PMID: 20192997

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