Prevalence of Anti-endothelial Cell Antibodies in Patients with Pulmonary Arterial Hypertension Associated with Connective Tissue Diseases

Objective To investigate the prevalence of anti-endothelial cell antibodies (AECAs) in the sera of connective tissue diseases (CTD) patients with pulmonary arterial hypertension (PAH) and its correlation with clinical manifestations. Methods AECAs in sera of 39 CTD patients with PAH,22 CTD patients without PAH,and 10 healthy donors as controls were detected with Western blotting. The prevalence of different AECAs in different groups was compared and its correlation with clinical manifestations was also investigated. Results The prevalence of AECAs was 82.1% in CTD patients with PAH,72.7% in CTD patients without PAH,and 20.0% in healthy donors. Anti-22 kD AECA was only detected in CTD patients with PAH (15.4%). Anti-75 kD AECA was more frequently detected in CTD patients with PAH than in those without PAH (51.3% vs. 22.7%,P<0.05). In CTD patients with PAH,anti-75 kD AECA was more frequently detected in those with Raynaud’s phenomenon or with positive anti-RNP antibody. Conclusion AECAs could be frequently detected in CTD patients with or without PAH,while anti-22 kD and anti-75 kD AECA might be specific in CTD patients with PAH.

Anti-endothelial cell antibody rich sera from rheumatic heart disease patients induces proinflammatory phenotype and methylation alteration in endothelial cells

Rheumatic heart disease(RHD)is a major cause of cardiovascular morbidity and mortality in developing nations like India.RHD commonly affects the mitral valve which is lined by a single layer of endothelial cells(ECs).The role of ECs in mitral valve damage during RHD is not well elucidated.In here,anti-endothelial cell antibody from RHD patients has been used to stimulate the ECs(HUVECs and HMVECs).ECs proinflammatory phenotype with increased expression of TNFa,IL-6,IL-8,IFNg,IL-1b,ICAM1,VCAM1,E-selectin,laminin B,and vimentin was documented in both ECs.The promoter hypomethylation of various key inflammatory cytokines(TNFa,IL-6,and IL-8),integrin(ICAM1)associated with leukocyte transendothelial migration,and extracellular matrix genes(vimentin,and laminin)were also observed.Further,the in-vitro data was in accordance with ex-vivo observations which correlated significantly with the etiological factors such as smoking,socioeconomic status,and housing.Thus,the study sheds light on the role of ECs in RHD which is a step forward in the elucidation of disease pathogenesis.