Plasma cell

Scheme electron microscopy. The mature plasma cell or plasmacyte (12-15 m) shows an eccentric nucleus (1) with a characteristic chunky distribution of heterochromatin along the inner nuclear membrane ('spoke-wheel' effect in light microscopy). Juxta-nuclearly an elaborate Golgi area (2) with secretion vacuoles together with centrioles (3) are often present (cytocenter). The cytoplasm is packed with long profiles of rough endoplasmic reticulum (RER) (4) with in between several mitochondria (5) confirming the secretory activity. Dependent on the cellular activity the RER vary from small or distended up to dilated profiles, in light microscopy this results in the deep basophilia of the cytoplasm and the light-stained centrosome (so-called nuclear 'hof').