Objectives: Autonomic dysfunction is closely associated with autoimmune diseases (AID) including primary biliary cirrhosis (PBC). The objective of this study was to determine the prevalence of anti-ganglionic (nicotinic) acetylcholine receptor (gAChR) antibodies in patients with AID.
Methods: We determined the presence of gAChR antibodies in serum samples from 146 patients (systemic lupus erythematosus [SLE] = 32; rheumatoid arthritis [RA] = 43; systemic sclerosis [SSc] = 38; PBC= 33) without information regarding autonomic symptoms, as well as 34 patients with other neurological diseases [OND], and 73 healthy controls [HC]. We specifically analyzed sera for anti-gAChRα3 and -β4 antibodies using the luciferase immunoprecipitation system (LIPS) assay.
Results: LIPS assay detected anti-gAChRα3 and -β4 antibodies in the sera from patients with SLE (12.5%, 4/32), RA (18.6%, 8/43), SSc (13.2%, 5/38), PBC (9.1%, 3/33), OND (2.9%, 1/34), and HC (0.0%, 1/73). There were no significant correlations between the levels of anti-gAChRα3 and -β4 antibodies, and the total titers of autoantibodies in AID.
Conclusions: The results demonstrated a significant prevalence of anti-gAChR antibodies in patients with AID, which is independent of the production of other autoantibodies in patients with autoimmune diseases. These anti-gAChR antibodies could mediate the autonomic dysfunction involved in the autoimmune mechanisms of AID.
Keywords: Anti-ganglionic acetylcholine receptor antibodies; Primary biliary cirrhosis; Rheumatoid arthritis; Systemic lupus erythematosus; Systemic sclerosis.