A study on biological activity of immune complexes deposited in glomeruli of various renal diseases in children

Abstract

The attachment of polymorphonuclear leukocytes (PMN) to glomeruli and the guinea pig complement fixation test (gp-CFT) were carried out on frozen sections from 53 children with various renal diseases to study the biological activity of immune complexes in glomeruli. In the control group, the number of attached PMN was very low. In the cases of membranous nephritis (MN), membranoproliferative glomerulonephritis (MPGN), and lupus nephritis (LN), the number of PMN increased significantly. In the cases of IgA nephritis and Henoch Schcnlein purpura nephritis (HSPN), the number of PMN increased but was less than in the cases mentioned above. The intensity and pattern of immunoglobulin and complement deposition in the glomeruli were not correlated with the number of PMN attached. There was a negative relationship between the level of serum complement and the number of PMN attached, but there was no relationship between circulating immune complexes (C. I. C.) and the number of PMN attached. The number of PMN attached in the HSPN cases was in inverse relation with the duration of the disease; however the number of PMN attached was the same no matter what the duration of the disease in the cases of IgA nephritis. The GP-CFT showed that GP-C3 was positive and GP-C4 was negative in the cases of IgA nephritis, HSPN, MPGN, and MN, but both were positive in the LN cases. It was proved that these methods are useful in analyzing the activity and mechanism of glomerulonephritis.