Heterogeneity of anti-mitochondrial antibodies: characterization and separation of the antigen associated with the pseudolupus erythematosus syndrome.

It could be shown that anti-mitochondria antibodies (AMA) found in drug-induced pseudolupus erythematosus syndrome (PLE) had a different specificity from those found previously in primary biliary cirrhosis (PBC). The PLE antigen could be easily separated from the PBC antigen either by isopycnic sucrose density gradient centrifugation of cytoplasmic extracts (supernatant 40) or purified sonicated rat liver or kidney mitochondria. The PLE antigen was firmly membrane-bound and, in contrast to the PBC antigen, not solubilized by treatment with various salts or enzymes. The ATP-ase complex, the probable target antigen of PBC-specific antibodies, did not react with sera from patients with the PLE syndrome. There is evidence that the PLE-associated antibodies (M3) occur exclusively in patients who have been sensitized to derivatives of pyrazolone or their metabolites, indicating that PLE antibodies may be specific markers for this type of drug allergy.