degranulation

biology

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Last updated

June 25, 2026

Quick Summary

Degranulation is the process by which cells release the contents of their granules. This occurs in various cell types, including mast cells and neutrophils.123

In mast cells, degranulation is triggered by allergens and releases mediators like histamine, which cause allergic reactions such as inflammation and swelling.2

Neutrophils, a type of white blood cell, also undergo degranulation. When neutrophils engulf bacteria, their granules release enzymes and reactive oxygen species to destroy the microorganisms. This process depletes the neutrophil's granules.43

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blood
Neutrophils
…the neutrophil are depleted (degranulation). A metabolic process within the granules produces hydrogen peroxide and a highly active form of oxygen (superoxide), which destroy the ingested bacteria. Final digestion of the invading organism is accomplished by enzymes.
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…the neutrophil are depleted (degranulation). A metabolic process within the granules produces hydrogen peroxide and a highly active form of oxygen (superoxide), which destroy the ingested bacteria. Final digestion of the invading organism is accomplished by enzymes.
Read More

mast cell
…their granules (a process called degranulation) into the surrounding tissues. The chemical mediators produce local responses characteristic of an allergic reaction, such as increased permeability of blood vessels (i.e., inflammation and swelling), contraction of smooth muscles (e.g., bronchial muscles), and increased mucus production.
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…their granules (a process called degranulation) into the surrounding tissues. The chemical mediators produce local responses characteristic of an allergic reaction, such as increased permeability of blood vessels (i.e., inflammation and swelling), contraction of smooth muscles (e.g., bronchial muscles), and increased mucus production.
Read More