An ultrastructural study of proliferative nephritis induced experimentally by a monoclonal antibody against mesangial cells: replacement of mesangial cells by cells of the monocyte-macrophage system.
An experimental nephritis accompanied by transient proteinuria can be produced by an intravenous injection of the monoclonal antibody, 1-22-3, raised against isolated rat glomeruli. The present study deals with the ultrastructural changes in the glomeruli in rats after the injection of this antibody. At 2 h after injection, all the mesangial cells had completely degenerated and neutrophils invaded most mesangial areas. Monocytes occupied the vacant mesangial areas at 24 h and gradually increased in number over the next 4 days. At 4 and 6 days, macrophage-like cells, possibly derived from monocytes, underwent frequent mitosis, resulting in a remarkable proliferation of these cells. The interpretation of these cells as macrophages was strongly supported by the fact that they contained previously injected latex particles in large numbers. From 2 to 4 weeks after injection, the macrophage-like cells gradually transformed into cells indistinguishable from normal mesangial cells. In the present experimental nephritis where all mesangial cells were initially destroyed, cells of the monocyte-macrophage system appear to play a leading role in the pathogenesis of the ensuing proliferative glomerulonephritis, and represent the source of the replacing mesangial cells.
Toyabe
S
S
Department of Pediatrics, Niigata University School of Medicine, Japan.
Iwanaga
T
T
D000818:Animals; D000911:Antibodies, Monoclonal; D002455:Cell Division; D004195:Disease Models, Animal; D005260:Female; D005920:Glomerular Mesangium / Q000473:pathology* / Q000648:ultrastructure; D005921:Glomerulonephritis / Q000139:chemically induced* / Q000473:pathology; D007678:Kidney Glomerulus / Q000473:pathology* / Q000648:ultrastructure; D008264:Macrophages / Q000473:pathology; D009000:Monocytes / Q000473:pathology; D051381:Rats; D011919:Rats, Inbred Strains
D000911:Antibodies, Monoclonal