THE STUDIES OF MASUGI NEPHRITIS WITH THE VARIOUS LABELING METHODS

It is well known that majority of the cases with glomerulonephritis are mediated by immunological events. Among the various types of glomerulonephritis, Goodpasture syndrome is typical model which mimick with Masugi nephritis (antiglomerular basement membrean (GBM) disease) . Recent numerous studies of Masugi nephritis using electron microscopy gave us various informations. However precise mechanism of the glomerular injuries are still unknown. On this points of view, precise glomerular injury of Masugi nephritis was investigated by using immunofluorescence, peroxidase staining and electron microscopical immunoautoradiography. GBM antibody which was obtained from rabbits immunized with rat GBM was used for induction of the Masugi nephritis. Masugi nephritis was studied by light-microscopy and electron-microscopy. For the detection of anti-GBM antibody in the tissue specimen, procedures of the immunofluorescent and peroxidase staining and also electron microscopical immunoautoradiography were performed. These three techniques were compared from the points of sensitivity and identifying power of localization of the antibody.<BR>By light-microscopy, glomeruli of rats received anti-GBM antibody showed accumulation of the polymorphonuclear leucocytes (PMN), hyalin thrombi and crescent formation. By electron-microscopy, the mild thickening of GBM, infiltration of PMN and platelet frequently seen in the glomeruli. By immunofluorescent study, rabbit IgG, rat C3 and rat C₁q were found along GBM in linear fashion. On the other hand, rat fibrin was occasionally found in the lumen of glomerular capillary. By peroxidase staining, the staining was seen in the both side of the glomerular capillary walls and the mesangial basement membrane.<BR>By electron microscopycal immunoautoradiography, a number of the grains were found along GBM, but the precise localization of the grains were not clearified whether they were in the lamina rara interna, lamina densa, or lamina rara externa, because spur of the grains was fairly long. The grains were also found in the mesangial area, surface of the epithelial cells and endothelial cells. In addition of these glomerular findings, the grains were found in the tubular basement membrane and also lumen of the tubules.<BR>These three immunological techniques, particularly electron microscopycal immunoautoradiography, seemed to be valuable methods for studying the mechanisms of the immunological glomerular injury.