Study On Anti-moesin Antibodies In Patients With Connective Tissue Diseases

BackgroundGenerally, connective tissue diseases (CTDs) represent a heterogeneous group of immunologically mediated inflammatory disorders. As a result of the inflammatory reaction a large variety of organs may be affected. Pulmonary involvement is frequent in the course of rheumatologic diseases, and may be due to various causes including infection and specific manifestations of the immune process. Interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH) are the most common features, and the leading causes of mortality in patients with CTD. In our previous research, immunoblotting revealed the presence of specific antibodies to a78-kDa membrane protein (78-kDa AECA) derived from EA.hy926in patients with CTD&PAH, which was correlated with Raynaud’s phenomenon, longer course and severity of PAH. This78-kDa protein was recognized as moesin with MALDI-TOF MS. Anti-moesin antibodies could be frequently detected in patients with CTD&PAH, which might play a role in the pathogenesis of PAH associated with CTD.Objectives1. To express, purify recombinant moesin, and establish ELISA and immunoblotting methods for detecting anti-moesin antibodies in sera of patients with CTD.2. To detect the anti-moesin antibody in patients with CTD-PAH, and to analyze the connection between the characteristics of CTD and the level of anti-moesin antibodies.3. To detect the positive rate of anti-moesin antibody in patients with pulmonary arterial hypertension(PAH) associated with Connective Tissue diseases (CTD), and analyze their clinical significance.3. To detect the positive rate of anti-moesin antibody in patients with Systemic sclerosis (SSc), which might be clinical significance. 4. To detect the positive rate of anti-moesin antibody in patients with primary Sjogren’s syndrome (pSS), which might be clinical significance.5. To localize moesin in human salivary glands, detect the target antigens of anti-moesin antibodies in patients with pSS.Methods1. With ACCESS software, established the clinical information databases for the patients with CTD-PAH and SSc separately.2. Expressed, purified recombinant moesin, and established ELISA and immunoblotting methods for detecting anti-moesin antibodies in sera of patients with CTD.3. With ELISA and western blotting, detected the positive rates of anti-moesin antibodies in patients with SSc, MCTD, SLE, pSS, SV, analyzed the correlation between anti-moesin antibodies and clinical characters.4. Immunofluorescence labeling with anti-moesin mAb in human salivary glands.Results1. The recombinant moesin was highly purified, the cut-off value of ELISA assay was Determined (0.158).2. The prevalence of anti-moesin antibodies by ELISA was52.5%in SSc,39.5%in MCTD,51.8%in SLE,69.2%in pSS, and22.5%in SV, significantly higher than those patients without CTD (5%)(p<0.010). The mean OD values of anti-moesin antibodies level in CTD without pulmonary involvement group, CTD-ILD group, CTD-PAH group, CTD-PAH&ILD group are as follows respectively:0.120±0.347,0.164±0.064,0.158±0.048,0.231±0.141.3. A higher positive rates of anti-moesin antibodies were related to Raynaud’s phenomenon, long course with more than5-year duration and severity of PAH. While AECA-78KD positive rate has no correlation to patients’ anti-U1RNP antibody, anti-SSA antibody and inflammation index including erythrocyte sedimentation rate, CRP, and complement.4. Serum anti-moesin Antibodies were present in34(37.7%) of the patients with SSc who were enrolled in EUSTAR:Compared with non-ILD group (9.1%), the positive rats of anti-moesin antibodies in SSc-ILD group is significant higher (45.2%)(p=0.037). Radiological patterns including diffuse patchy ground-glass opacities, basal irregular lines and consolidation on HRCT scan is correlation with the level of anti-moesin antibodies.5. Serum anti-moesin Antibodies were present in28(37.8%) of the patients with pSS who were enrolled in SICCA. Compared with anti-moesin Abs negative group, the unstimulated flow rates were significantly decreased in anti-moesin Abs positive group. In addition, the levels of anti-moesin antibodies are correlated with several features of disease, including hyperglobulinemia, lacrimal and salivary dysfunctions, as well as salivary gland infiltrates.6. Moesin can be detected by IIF on the epithelial cell of labial glands. Immunofluorescence labeling with anti-moesin mAb was found in both serous acini and mucous acini in labial glands. Labeling was found at the luminal side of duct cell.Conclusions1. Anti-moesin antibodies could be found more frequently in patients with CTD than those without CTD by ELISA. CTD patients with different target organ involved has different positive rate of anti-moesin antibodies.2. Anti-moesin antibodies could be found more frequently in CTD patients with pulmonary involvement (mainly PAH and ILD).3. Serum anti-moesin Antibodies were present in the patients with SSc-ILD. The presence of anti-moesin Antibodies in serum appeared to be connected with more severe pulmonary function damage in SSc-ILD.4. Serum anti-moesin Antibodies were present in the patients with pSS. The presence of anti-moesin Antibodies in serum appeared to be connected with more severe lacrimal gland function and salivary gland function damage, as measured by Schirmer test and unstimulated flow rate separately.5. Moesin is one of the auto-antigen recognized by anti-moesin antibodies in labial glands of patient with pSS.