Anticytoplasmic antibodies in systemic lupus erythematosus

By the indirect fluorescent antibody technique, sera of patients with systemic lupus erythematosus were used to stain the cytoplasm of proximal tubule cells of rat kidney frozer sections and the cytoplasm of cells in frozen sections of rat liver. Since the cytoplasmic stainings of rat liver were absorbed with ribosomes and the stainings of proximal tubules were absorbed with mitochondria, the sera were thought to contain either anit-ribosomal antibodies or anti-mitochondrial antibodies. By Ouchterlony methods, some sera produced precipitin lines against 105,000 G supernatant of rat liver homogenate distinct from the ribosomal system. This antigen activity was present in the first peak of a Sephadex G-100 column chromatograph.