Dictionary > Eosinophil

Eosinophil

Definition
noun, plural: eosinophils
A type of polymorphonuclear leukocyte characterized by having a kidney-shaped nucleus, presence of cytoplasmic granules that render the cell pink or orange when stained with the usual dyes (e.g. H&E stain), and whose immune function is primarily for allergic inflammatory responses and against parasitism
Supplement
The polymorphonuclear leukocytes are characterized by having nuclei with three or more lobes joined by filamentous connections and cytoplasmic granules perceptible through conventional staining (e.g. H&E stain) and light microscopy. In humans, the polymorphonuclear leucocytes may be subdivided into eosinophils, basophils and neutrophils according to the staining properties of the granules. The eosinophils, in particular, are so named because it is readily stained by eosin. It stains pink to orange hues when stained with usual dyes (e.g. H&E stain).
Similar to other polymorphonuclear leukocytes, the eosinophil goes through the granulocytic series of hematopoiesis. Its developmental stages are as follows: hemocytoblast → common myeloid progenitor (or CFU-GEMM) → CFU-GM → CFU-G → myeloblast → eosinophilic promyelocyte → eosinophilic myelocyte → eosinophilic metamyelocyte → eosinophilic band cell → eosinophil. The main function of the eosinophils is to destroy parasitic organisms (e.g. enteric nematodes). They also play a major role in allergic reactions. They secrete chemical mediators that can cause bronchoconstriction in asthma.
The eosinophil has kidney-shaped nucleus (usually two-lobed) and a size ranging from 10 to 12 μm. In humans, the eosinophils account for the 2.3% of the total white blood cells in the body.
Synonym(s):

  • acidophilic leukocyte
  • eosinophilic leukocyte
  • acidophil
  • eosinocyte
  • oxyphil
  • oxyphile
  • oxyphilic leukocyte

See also:

  • blood
  • leukocyte
  • polymorphonuclear leukocyte
  • neutrophil
  • basophil
  • hematopoiesis
  • granulopoiesis
  • inflammation
  • parasite
  • eosinophile


  • You will also like...

    An artist's depiction of the origin of amphibians
    Amphibians & Early Reptiles

    Obtaining air outside an aquatic environment required species to acquire suitable adaptations, and this was the case of ..

    Oligodendrocyte and Schwann cell
    The Central Nervous System

    Myelin sheath is essential for a faster conductivity of signals. Know more about this feature of some neurons in the Cen..

    An artistic depiction of Dunkleosteus fish
    Fish

    The sea was teeming with life. Eventually, through reproduction and continued variation, fish came about. There are over..

    New Zealand Flora & Fauna
    Ecology & Biodiversity: New Zealand Flora & Fauna

    New Zealand is known for its unique biodiversity, caused by its remarkable geography and geologic history. Breaking away..

    Schematic diagram of bacterial lactose operon
    Gene Action – Operon Hypothesis

    Learn how the way genes control and determine every aspect of the body. This lesson uses lac operon as an example. ..

    ..

    takahē
    Takahē (Porphyrio hochstetteri)

    Meet the colorful takahē, an extremely rare flightless bird. Find out more about its unique features and why they matte..

    Related Articles...

    No related articles found

    See all Related Topics