Experimental autologous immune-complex nephritis: An electron microscope and immunohistochemical study

Abstract A correlative ultrastructural and immunohistochemical study of the kidney has been performed in rats with autologous immune-complex nephritis, induced by repeated injections of tubular antigens incorporated in Freund's adjuvant. In the glomeruli, electron-dense deposits located on the epithelial half of the capillary basement membrane were seen. The cytoplasm of the foot processes located close to the intramembranous deposits showed an electron-dense material with similar morphologic features. The basement membrane of the proximal tubes was markedly increased in thickness and presented electron-lucid areas. By means of acid phosphatase-labeled antibodies against rat γ- and β - 1 C globulins it was possible to demonstrate that the glomerular electron-dense deposits and the proximal tube basement membrane contained autologous globulins. On the basis of these observations it was suggested that the immune complexes responsible of the renal damage locate selectively in those parts of the nephron which normally deal with the filtration and resorption of proteins, and that the pedicels of the glomerular epithelial cells are engaged in the removal of the intramembranous deposits.