Title: Basophilic granulocyte (peripheral blood, human).
Description: Electron microscopy.
The bilobed nucleus (2) is surrounded by moderate amount of organelles. The cell exhibits few short filopodia (arrows). The large coarse basophilic granules (1) (specific granules) vary in density and contain vasoactive mediators such as heparin, histamine, sulphated proteoglycans, leucotriene 3.
The basophilic granulocytes do not contain the myelin figure-like (scrolls-like) inclusions as found in the mast cells. Rarely, (light microscopic) azurophilic granules (=peroxidase-positive lysosomes) are detectable.
Background: The cells contain IgE receptors for binding allergens, resulting in exocytosis of the granules, releasing e.g. histamine and other vasoactive mediators resulting in an anaphylactoid reaction (immediate hypersensitivity).
Keywords/Mesh: blood, bone marrow, basophilic granulocyte, specific granule, mast cell, histamine, histology, electron microscopy, POJA collection