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...

    IQ, Creativity and Learning
    IQ, Creativity and Learning

    Human intelligence provided the means to utilize abstract ideas and implement reasoning. This tutorial takes a further l..

    Schematic diagram of DNA replication
    DNA Structure & DNA Replication

    DNA is a double helix structure comprised of nucleotides. A nucleotide, in turn, is made up of phosphate molecule, deoxy..

    Geological Periods
    Geological Periods

    Geological periods is a study guide that cites the different geological periods on Earth's timeline. Each has a brief ov..

    Gibberellins and Gibberellic Acid
    Gibberellins and Gibberellic Acid

    This tutorial describes the role of gibberellin family in plants. Find out the effects of gibberellin on plant growth an..

    New Zealand - Biodiversity fauna
    New Zealand’s Biodiversity

    Find out more about New Zealand's unique biodiversity by exploring a range of different ecosystems and the key role of s..

    Regulation of Biological Systems
    Regulation of Biological Systems

    Regulation of Biological Systems tutorials are focused on the modulation of biological systems from cell to population l..