Nuclear matrix antibodies in rheumatic diseases.
We describe a new type of human antinuclear antibody (ANA) reacting with the nuclear matrix by indirect immunofluorescence technique. Cultured cells of human and animal origin were used as substrate. Before assay, cells were extracted with buffers to remove other components of the nuclei leaving the matrix intact. Two types of immunofluorescence staining patterns were seen: homogenous and speckled. When human embryonic fibroblasts were used as targets, sera from patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) contained significantly more nuclear matrix antibodies of the homogenous type than the control group. These antibodies were often, especially in SLE, species cross-reacting. (When PTK-2 cells were used as substrate the difference between SLE and RA was also significant [60 vs 8%]). Antibodies with speckled staining pattern were seen only in the patient sera. Their highest incidence (35%) was found in sera from patients with the primary sicca syndrome. The nuclear matrix may be a major target for ANA in rheumatic diseases.
D000974:Antibodies, Antinuclear / Q000276:immunology*; D004591:Electrophoresis, Polyacrylamide Gel; D005347:Fibroblasts / Q000276:immunology; D005455:Fluorescent Antibody Technique; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D012216:Rheumatic Diseases / Q000276:immunology*
D000974:Antibodies, Antinuclear; D007106:Immune Sera