A case report and the role of U1-snRNP complex autoimmunity in clinical presentation similar to generalized urticarial

Chronic inflammatory rheumatic diseases are often characterized by serum autoantibodies directed against ubiquitous nuclear components.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).This autoantibody in one patient caused the clinical symptoms of generalized urticaria to be detected by allergic and autoantibody tests that showed no allergenicity, but the ui-snRNP autoantibody was positive.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.

کلیدواژه ها:

U1-snRNP- Autoimmunity- Urticaria