Identification of Moesin as a Novel Autoantigen in Patients with Sjogren's Syndrome.

BACKGROUND: SjOgren's Syndrome (SS) is a systemic and chronic autoimmune disorder that affects the exocrine glands with massive autoantibody production. Although the pathogenesis of the disorder is incompletely understood, but some studies have reported that anti-moesin antibodies have been detected in autoimmune diseases with which SS is closely associated. Here, we have investigated moesin's potential involvement in SS. OBJECTIVE: This study aims to verify whether moesin is a specific autoantigen involved in Chinese Hans SS patients. METHODS: First, recombinant human moesin was expressed and purified. Next, the protein was verified as antigen by Western blotting and immunoprecipitation. The positive protein band in the immunoprecipitation was identified by (MALDI-TOF/TOF). Finally, an optimized ELISA (Enzyme- Linked Immunosorbent Assay) kit was developed to measure the titer concentration of anti-moesin antibody-positive patients in a large cohort of clinical subjects. RESULTS: Univariate analysis revealed that the proportion of individuals positive for serum IgG against recombinant human moesin was 42 % in a group of Chinese Hans SS patients (21 of 50), 22 % in systemic lupus erythematosus patients and (11 of 50), compared to only 4 % in healthy controls (2 of 50). CONCLUSION: An association between anti-moesin antibodies and SS manifestation have been found which may be considered a suspected serum biomarker for the development of SS.