ROLE OF ENDOTHELIAL-CELLS IN THE DEVELOPMENT OF GLOMERULAR-LESIONS OFMESANGIOCAPILLARY GLOMERULONEPHRITIS

The histological and ultrastructural changes of mesangiocapillary glom erulonephritis (MCGN) are not unique to this entity: splitting of base ment membrane (BM) is seen in a number of conditions with an altered c oagulation pattern. The distribution of endothelial cells in the glome rular capillaries in five cases of MCGN was studied by light and elect ron microscopy and immunocytochemistry; endothelial cells were stained with peroxidase or FITC-conjugated antibodies against Factor VIII-rel ated antigen or CD34 antigen and observed with conventional light/immu nofluorescence microscopy and confocal laser scanning microscopy for t hree-dimensional reconstruction. Electron microscopy was performed wit h colloidal gold labelling. Endothelial cells were shown to be present within the duplicated basement membranes of capillaries and continuit y was demonstrated with endothelial cells lining the capillary lumina. These results suggest that endothelial cells as well as mesangial cel ls can participate in the formation of the characteristic double conto ur of capillary walls in MCGN, especially in the early stages. There a re some similarities to the changes seen in larger arteries as a conse quence of thrombotic disease.