Altered metabolism of poly(ADP-ribose) in the peripheral blood lymphocytes of patients with systemic lupus erythematosus.

A method was developed to measure poly(ADP-ribose) metabolism in peripheral blood lymphocytes. The technique involved the isolation of lymphocytes on Ficoll gradients, followed by lysis with 5M NaCl. The synthesis and degradation of poly(ADP-ribose) in this crude lysate, measured by the incorporation of 3H-labeled NAD into acid-precipitable counts, was compared in 18 patients with systemic lupus erythematosus (SLE), 10 patients with rheumatoid arthritis, and in 10 control patients without rheumatoid arthritis. Patients with SLE showed a 70% decrease in poly(ADP-ribose) synthesis (P less than 0.001); this decreased synthesis persisted even with the addition of histones or DNase. We present possible explanations of the role of poly(ADP-ribose) in SLE.