[DNA metabolism in lymphocytes of patients with lupus nephropathy].

DNA metabolism in lymphocytes was evaluated in patients suffering from the nephrotic syndrome decompensation, basing on measurement of endonucleases (DNases) activity in these cells. The examination involved 17 patients, aged 27.7 +/- 7.11 with clinical and biochemical active disease, all with the nephrotic syndrome decompensation and erythrocytes in urine. A significant rise in the enzyme activity was observed in T and B lymphocytes (p < 0.001) in all the patients, with a distinct 3-fold increase in enzyme activity in B lymphocytes, when compared with the other cell populations. To elucidate the nature of the observed changes in DNases activity in systemic lupus erythematosus, nucleus proteins of the cells were separated electrophoretically in acrylamide gradient with immobilized DNA. Degradation processes in nucleic acids were considerably more efficient than the DNA synthesis in B lymphocytes of these cells. A smaller increase in the enzyme activity in T cells than in B lymphocytes results exclusively from more intense catabolism of nucleic acids not parallel to the intensified DNA synthesis in these cells.