Antibodies to histones of the IgG and IgM class in systemic lupus erythematosus.

Antibodies to histones were measured by an ELISA. Histone antibodies of the IgM class could be detected in other diseases than SLE, as well as in healthy persons. However, IgG histone antibodies proved to be specific for SLE and could be found in 21% of the SLE patients. These antibodies were highly associated with dsDNA antibodies of the IgG class. We could not find any correlation between IgG histone antibodies and clinical symptoms of SLE. IgG histone antibodies mostly reacted equally with all tested histone fractions.