The macrophagen in human rapidly progressive glomerulonephritis.

Glomeruli from 18 "normal" patients and from 35 patients with glomerulonephritis have been maintained in tissue-culture and examined by time-lapse cinemicroscopy and electron microscopy. At least two distinct cell types with features of epithelial and mesangial cells emerge in the outgrowths from normal and non-crescentic glomeruli. 4 patients with rapidly progressive glomerulonephritis formed a distinct subgroup. Glomerular culture revealed that their crescents contained large numbers of macrophages. This suggests that, contrary to belief, the crescents in rapidly progressive glomerulonephritis consist of accumulated macrophages rather than proliferated epithelial cells.