Determination of the serum anti-extracted nuclear antigens autoantibodies in the patients with connective tissue disease by quantitative ELISA

Objective To study the clinical significance of the quantitative determination of the various anti extracted nuclear antigens(ENA) autoantibodies in the various connective tissue disease (CTD). Methods The levels of various anti ENA autoantibodies in the serum from 128 CTD patients, 50 non CTD patients and 60 healthy persons were determined by a quantitative sandwich ELISA kit. The prevalence of these antibodies were also determined in 60 healthy persons. Results High level and positive rate of anti Sm antibody were detected in systemic lupus erythematosus(SLE), anti ul RNP antibody in SLE and mixed connective tissue disease (MCTD) anti SSA and SSB antibody in Sjogren's syndrome (SS), anti Scl 70 antibody in progress systemic scleroderma(PSS), and anti Jo 1 antibody in polymyositis/dermatomyositis(PM/DM). The level and positive rate of these autoantibodies were significant higher than that of non CTD patients and healthy persons ( P 0.01). Conclusions The various anti ENA autoantibodies can be quantitatively detected by the quantitative sandwich ELISA kit and the detection of these anti ENA autoantibodies is useful for diagnosis of patients with various CTD.