EFFECT OF PREFORMED IMMUNE-COMPLEXES ON THE CLEARANCE AND TISSUE LOCALIZATION OF SINGLE-STRANDED-DNA IN MICE

  • 1 January 1980
    • journal article
    • research article
    • Vol. 40  (2) , 264-272
Abstract
DNA is cleared from the circulation extremely rapidly by the liver and normal individuals have low or immeasurable levels of circulating DNA. In some patients with SLE [systemic lupus erythematosus] and in NZB/W mice, significant amounts of free DNA and DNA-anti-DNA immune complexes are found in the circulation, suggesting a possible defect in DNA clearance in these conditions. To delineate factors which might contribute to the persistence of DNA in the circulation, the effects of immune complexes on the clearance of single stranded [ss] DNA in normal C57B1/6J mice were assessed. HSA[human serum albumin]-anti-HSA immune complexes at 5-fold antigen excess were injected i.v. and after a variable interval the clearance of ssDNA was determined. Clearance of all doses of DNA was markedly suppressed 6-12 h after the administration of immune complexes and returned to normal by 24 h. Immune complexes decreased DNA clearance by blocking the hepatic uptake of DNA without altering the distribution of DNA to other organs. Histology and studies on the effect of immune complexes on the clearance of bromosulfophthalein (BSP) and S colloid suggest that immune complexes affect DNA clearance by altering hepatic blood flow. Circulating immune complexes in patients with SLE or other conditions may suppress normal DNA clearance and contribute to the persistance of DNA in the circulation.