Plasma cell with Russell bodies (nose septum, rat)

Electron microscopy. This mature plasma cell exhibits in the cytoplasm dilated rough endoplasmic reticulum (1) filled with electron-grey material as well as electron-dense granules (2) of varying sizes (antibodies). These electron-dense granules are made up of accumulated (crystallin) immunoglobulins within the lumen of the rough endoplasmic reticulum cisternae (so-called Russell bodies). Hyperstimulation can result in the formation of these Russell bodies, easily detectable in light microscopy. (3) Collagen fibers in the nose septum.