INVIVO CLEARANCE AND TISSUE UPTAKE OF AN ANTI-DNA MONOCLONAL-ANTIBODY AND ITS COMPLEXES WITH DNA

Abstract

In vivo clearance and tissue localization of a purified mouse anti-DNA monoclonal antibody (MoAb) (A52 IgG2b) and its complexes with DNA were studied in normal BALB/c and autoimmune NZB/NZW mice. The plasma half-life of the autoantibody in both mouse strains was significantly shorter (T1/2 [half-life] = 10-15 min), compared with that of purified NZB myeloma proteins (T1/2 .gtoreq. 180 min). DNA antigen and DNA-A52 IgG complexes in antibody excess were cleared very rapidly (T1/2 = 4-8 min), while complexes formed in antigen excess persisted in the circulation much longer (T1/2 = 60 min). Organ studies showed that the anti-DNA MoAb was transiently retained by the liver and the spleen but demonstrated a particular affinity for the kidney tissue. Evidently, tissue damage in SLE [system lupus erythomatosus] glomerulonephritis may be facilitated by direct interaction of anti-DNA antibodies with glomerular components.