[Antibodies against extractable nuclear antigens. Clinico-biological correlations in 100 cases].

The clinical significance of antibodies directed against extractable nuclear antigens with currently well-known antigenic targets, is studied in 100 patients affected with various connective tissue inflammations. The anti-Sm is the most frequently encountered antibody in lupus disease and overlapping connective tissue inflammations with a lupus component while the anti-RNP is related to mixed inflammation of the connective tissue and the dry syndrome. These antibodies, without being specific markers for a given disease, represent an additional biological argument for a better nosological classification of connective tissue inflammations. The use of immuno-impression, a more sensitive technique than immunodiffusion, could provide a better understanding of the immune response during these diseases and specify the diagnostic and prognostic value of various auto-antibodies. Analysis by immuno-impression of 36 sera among the 100 with antibodies directed against extractable nuclear antigens has enabled us to compare the two techniques and study the different specificities of these antibodies.