Author/Editor		Žigon, Polona; Čučnik, Saša; Ambrožič, Aleš; Tomšič, Matija; Hočevar, Alojzija; Sodin-Šemrl, Snežna; Kveder, Tanja
Title		Prevalence of autoantibodies against a second extracellular loop of M3 muscarinic acetylcholine receptor in Sjögren's syndrome
Type		članek
Vol. and No.		Letnik 3
Publication year		2014
Language		eng
Abstract		Antibodies against the M3 muscarinic acetylcholine receptor (M3R) are postulated to have inhibitory effects on parasympathetic neurotransmission in patients with Sjögren's syndrome (SS) leading to lacrimal and salivary glandular dysfunction. The 2nd extracellular loop domain of M3R (2ndM3R) is regarded as the main epitope for autoantibodies. The aim of our study was to establish and optimize the determination of autoantibodies against 2ndM3R using sera from patients with SS (107), systemic lupus erythematosus (SLE) (98), antiphospholipid syndrome (3) and healthy individuals (157). A 25-mer synthetic peptide (2ndM3R) [KRSE213-237] was synthesized and used as the antigen for anti-2ndM3R ELISA. Positive values were measured in 11 SS patients (10%) and 4 with SLE (4%), showing a significantly higher prevalence of anti-2ndM3R in patients with SS as compared to SLE and healthy controls (p=0.029 and p<0.001, respectively). Our method enabled reliable detection of anti-2ndM3R and revealed low prevalence of anti-2ndM3R in our population of SS patients.
Keywords		muscarinic acetylcholine receptor autoantibodies Sjögren's syndrome muskarinski receptor acetilholin avtoprotitelesa Sjogrenov sindrom