[Detection of antibodies to extractable nuclear antigens with counterimmunoelectrophoresis and the Western blot technic].

Detection of antibodies against extractable nuclear antigens (ENA) by counter immunoelectrophoresis (CIE) is currently used to screen sera from patients with collagen vascular disease. Although fast and reliable, the method has its limitations with regard to the differentiation of various antigen-antibody systems. In this study, results of the anti-ENA analysis by CIE and by Western-Blot technique are compared. Except for a higher frequency of Sm antibodies by Western-blot, the results of CIE were confirmed. The source of antigen and the higher sensitivity of the Western-Blot technique are responsible for the different results obtained. With respect to the relationship of antibody profile and illness, both methods demonstrated a high frequency of antibodies against U1-sn-RNP in mixed connective tissue disease and of anti-SS-B antibodies in Sjögren's syndrome.