Specific granule
From Wikipedia the free encyclopedia
Specific granules are secretory vesicles found exclusively in cells of the immune system called granulocytes.
It is sometimes described as applying specifically to neutrophils,[1] and sometimes the term is applied to other types of cells.[2]
These granules store a mixture of cytotoxic molecules, including many enzymes and antimicrobial peptides, that are released by a process called degranulation following activation of the granulocyte by an immune stimulus.
Specific granules are also known as "secondary granules".[3]
Contents
[edit]Examples of cytotoxic molecule stored by specific granules in different granulocytes include:
- Neutrophil: alkaline phosphatase, lactoferrin, lysozyme, NADPH oxidase
- Eosinophil: cathepsin, major basic protein
- Basophil: heparin, histamine (not directly cytotoxic)
Clinical significance
[edit]A specific granule deficiency can be associated with CEBPE.[4]
References
[edit]- ^ "Definition: specific granule from Online Medical Dictionary".
- ^ Okuda M, Takenaka T, Kawabori S, Ogami Y (July 1981). "Ultrastructural study of the specific granule of the human eosinophil". J. Submicrosc. Cytol. 13 (3): 465–71. PMID 7334549.
- ^ John P. Greer; Maxwell Myer Wintrobe (1 December 2008). Wintrobe's clinical hematology. Lippincott Williams & Wilkins. pp. 173–. ISBN 978-0-7817-6507-7. Retrieved 10 November 2010.
- ^ Online Mendelian Inheritance in Man (OMIM): SPECIFIC GRANULE DEFICIENCY; SGD - 245480
External links
[edit]- Neutrophil granules at sav.sk Archived 27 November 2006 at the Wayback Machine