AN ACTIVE MODEL OF IMMUNE-COMPLEX GLOMERULONEPHRITIS IN THE RAT EMPLOYING CATIONIZED ANTIGEN

  • 1 January 1983
    • journal article
    • research article
    • Vol. 112  (2) , 185-194
Abstract
An active model of in situ immune complex glomerulonephritis involving a cationic antigen was established. Three weeks after immunization with human IgG, the left kidneys of Wistar rats were perfused with 100 .mu.g of cationized human IgG (pI > 9.5) via the left renal artery. At this time the animals exhibited a mean serum concentration of 0.58 .+-. 0.33 mg anti-human IgG antibody/ml. Renal tissue was examined at regular intervals by immunofluorescence, light microscopy and EM, thereafter. Cationized human IgG and rat IgG were distributed along the glomerular capillary wall in a pattern that became increasingly granular with time; rat C3 [complement component 3] was also present. Histologically, a severe proliferative lesion was seen with crescent formation in 10-20% of the glomeruli; adhesions of glomerular tufts to Bowman''s capsule were common and with time spike formation in the glomerular basement membrane became very prominent. Extensive subepithelial dense deposits were seen by EM. Proteinuria was present in 19 of 26 animals within 24 h, and in 30 of 31 by day 7. Protein excretion fell from day 14 onward, but some animals exhibited chronic proteinuria. The model described represents another situation in which cationic antigens can induce subepithelial immune complexes, namely the rapid release of small quantities of antigen into a previously sensitized host. This sequence could well mirror the events occurring in nature more closely than the previously described passive in situ model.