Comparative Electron and Immunoelectron Microscopic Studies on Immunoglobulin Deposits in the Glomeruli of the Kidney, Skin, Esophagus and Uterus of MRL/l Mice.

Immunoglobulin (Ig) deposits in the glomeruli of the kidney, lesional skin, upper esophagus and lower cervical part of the uterus of MRL/l mice were comparatively studied by immunoelectron and plain electron microscopy. The massive reaction products in immunoelectron microscopy indicating Ig deposits in the glomeruli of the kidney were observed as electron-optically dense masses by plain electron microscopy. In the skin, esophagus and uterus of the mice, the granules or small masses of reaction products were distributed along the basement membrane zone in association with pathologically increased or normal filamentous constituents such as collagen fibrils, anchoring fibrils, basal lamina or basal lamina-like material and intradermal hemidesmosome-particles. However, plain electron microscopy revealed no obviously pathologic granules or masses in association with the filaments in these organs. These results suggest the possibility that the Ig deposits in the skin, esophagus and the uterus of the MRL/l mice are different in quality and formed in a manner different from those of the glomeruli of the kidney.