ANTIBODIES TO HMG PROTEINS IN PATIENTS WITH DRUG-INDUCED AUTOIMMUNITY

Objective. To determine the prevalence of autoantibodies to high-mobil ity group (HMG) proteins in sera from patients with drug-induced lupus (DIL). Methods. Forty-two patients who developed autoantibodies and/o r lupus after treatment with procainamide or other drugs were tested f or HMG autoantibodies by immunoblotting and enzyme-linked immunosorben t assay (ELISA). Results. Twenty-eight of the 42 sera (67%) bound HMG- 14 and/or HMG-17. In comparison, 9 of 42 (21%) bound HMG-1 and/or HMG- 2. There was a good correlation between ELISA results and binding on i mmunoblots. Conclusion. The high prevalence of antibodies to the nucle osomal core HMGs (HMG-14 and HMG-17) in DIL patients adds evidence imp licating nucleosomes as immunogens in drug-induced autoimmunity.