Rearrangement of immune complexes in glomeruli leads to persistence and development of electron-dense deposits.

Abstract
Covalently, cross-linked immune complexes were prepared with multivalent 2-nitro-4-azidophenyl.cntdot.human serum albumin (NAP.cntdot.HSA) and antibodies to NAP at 5 times antigen excess. After purification with gel filtration, affinity chromatography with antigen-agarose column, and addition of the hapten, 9.5% of the antibodies dissociated from the complexes by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. After injection of these cross-linked immune complexes into mice, glomeruli stained for the complexes by immunofluorescence microscopy for only a few hours and electron-dense deposits were not detected. When the same immune complexes with comparable lattice but without covalent cross-linking were administered to a 2nd group of mice, the initial deposition by immunofluorescence was comparable and then increased to extensive deposits that persisted to 96 h. In this 2nd group of mice extensive electron-dense deposits evolved. These observations supported the conclusion that the immune complexes initially deposited from circulation must undergo rearrangement to persist and to form electron-dense deposits in glomeruli. The covalently cross-linked immune complexes existed in glomeruli only for a short period of time since these complexes could not rearrange.