Title: Basophilic granulocyte in peripheral blood smear (human)
Description: Stain: May-Grünwald-Giemsa (MGG).
The basophilic granulocyte has large, coarse dark purple-stained granules that contain mediators such as eosinophilic chemotactic factors, heparin, histamine, myeloperoxidase. The nuclear lobes are irregular, badly visible and covered by the granules.
Background: Basophil (and mast cell) granules contain biogenic amines and enzymes as well as cytokines and lipid mediators, which are largely newly synthesized on cell activation. The biogenic amines (e.g. histamine) and the lipid mediators (e.g. PAF, PGD2, LTC4) cause vascular leak, bronchoconstriction and intestinal hypermotility. The cytokines (e.g TNF-α, MIP-1α, Il-3, -4, -5, -13), lipid mediators, and enzymes (e.g. tryptase) contribute to inflammation reaction and tissue damage, respectively. Like mast cells, the basophils express FcεRI, bind IgE and can be triggered by antigen binding to the IgE.
Keywords/Mesh: blood, bone marrow, basophilic granulocyte, histology, POJA collection