154 of 255 individual human renal biopsies studied by immunofluorescence contained varying combinations of immunoglobulins (Ig), complement (C) components C1q, C3, C4, C5, C6, C8, C3 proactivator (C3PA), and/or properdin. 10 patients had linear deposits of Ig in glomeruli characteristic of antiglomerular basement membrane (GBM) antibodies; nine patients had C3 deposits (minimal in three) with generally lesser amounts of C1q, C4, C5, C6, and/or C8. 118 of the patients had granular deposits of Ig, suggesting immune complex glomerulonephritis; 114 of these had deposits of C3, usually accompanied by C1q, C4, C5, and/or C6. These observations indicate that the entire C sequence is deposited in glomeruli in most Ig-mediated glomerulonephritides. However, certain cases of anti-GBM glomerulonephritis with few or no C deposits may utilize pathways of injury independent of C.
Pierre J. Verroust, Curtis B. Wilson, Neil R. Cooper, Thomas S. Edgington, Frank J. Dixon