Title: Eosinophilic granulocyte in peripheral blood smear (human)
Description: Stain: May-Grünwald-Giemsa (MGG).
The eosinophilic granulocyte usually has two to three nuclear lobes. The brown-orange granules are large, solitary and contain pharmacologically active mediators. The cell surface is occupied with IgE receptors.
Background: The primary function of eosinophils is defense against parasites. Stored in the cytoplasmic granules one finds major basic protein (MBP) and eosinophil cationic protein (ECP) which both are toxic to parasites. The cell also produces lipid mediators upon activation, e.g. leukotrienes C4, D4, E4 and lipoxins eliciting prolonged bronchoconstriction, mucus secretion and increased vascular permeability, and promoting inflammation as well. The cytokines produced on activation (e.g. IL-3, -5, -8, -10, GM-CSF, MIP-1α, eotaxin) promote eosinophils production and activation as well as chemotaxis of leukocytes.
Keywords/Mesh: blood, bone marrow, eosinophilic granulocyte, histology, POJA collection